JP7331678B2 - Polypropylene resin composition and foamed sheet - Google Patents

Description

INDUSTRIAL APPLICABILITY The present invention makes it possible to provide a foamed sheet in which foamed cells have a high closed cell property during foaming molding, the cells are dense and the size is relatively uniform, and in particular, the T-die method has a high foaming rate of 3.0 times or more. The present invention relates to a polypropylene-based resin composition suitable for producing a sheet of magnification, a foamed sheet using the same, and a molded article thermoformed using the same.

One of the important molding methods for polypropylene resin is foam molding. Various molded articles obtained by extrusion foam molding and injection foam molding are used in a wide range of applications, taking advantage of their excellent properties such as heat insulation, sound insulation, cushioning, and energy absorption. Especially in recent years, from the viewpoint of environmental problems, the weight reduction of materials and the reduction of the environmental load have become important issues for technological development, and the technological fields in which foam molded products are used tend to expand. , is intensifying.
Regarding the foaming performance, the independence and size of the cells are important factors, and it is important how to increase the independence of the cells and make the size uniform and dense. In addition, such a molded article is also suitable in that it has a high appearance. In the food packaging field in particular, containers for side dishes and lunch boxes are produced by foam molding. design) is required.
Extrusion foam molding is generally used as a molding method for food foam trays, foam containers, etc. Among extrusion foam molding methods, there are a T-die method and a round die method. The advantage of the T-die method is that the foamed sheet is generally cooled by a mirror surface roll immediately after extrusion, so that the surface of the foamed sheet is excellent in gloss and has a relatively good appearance compared to the round die method described later. On the other hand, however, since the foamed sheet is handled by the mirror surface rolls, it is difficult to maintain the independence of the cells. This is because, as the sheet has a high expansion ratio of more than 3.0 times, the collapse of the cell wall due to the growth of the cells makes it easier for the cells to coalesce, so that the independence of the cells can be maintained. It becomes difficult to maintain high appearance.
In addition, regarding sheet molding by the round die method, there is no rapid cooling of the foamed sheet with mirror surface rolls, so compared to the T die method, the gloss and appearance of the sheet surface tend to be inferior, but on the other hand, high foaming There is also a feature that a sheet of magnification can be obtained.
For materials with excellent foamability, conventionally, based on long-chain branched polypropylene with high melt tension suitable for foam molding, a specific propylene-ethylene block copolymer polymerized with a Ziegler-Natta catalyst is blended. Materials have been developed for the purpose of achieving both foaming aptitude and container appearance (Patent Documents 1 to 3).
On the other hand, in extrusion molding typified by the T-die method, in order to increase productivity, it is common practice to increase the screw rotation speed of the extruder and increase the sheet take-up speed. In the environment where the sheet is formed by shearing heat generated by the resin, excessive take-up tension is generated in the foam sheet by raising the resin temperature and taking-up speed, causing deformation, coalescence, and breakage of the cells. easier. In addition, in such an environment, it is impossible to obtain a foam sheet of 3.0 times or more, especially by the T-die method, with conventional materials. There was a strong demand from the market for the development of materials to obtain

Japanese Patent No. 5624851 Japanese Patent No. 6064668 Japanese Patent No. 6089765

In view of the current state of the prior art, it is an object of the present invention to have uniform and fine foam cells at a foaming ratio of 3.0 times or more, especially in an environment where high-speed molding is performed by the T-die method of extrusion foaming. Provided is a resin composition for obtaining a polypropylene resin (multilayer) foam having a good appearance, a polypropylene resin (multilayer) foam sheet using the same, and a thermoformed molding using the same. It is to provide the body.

The present inventors have made intensive studies to solve the above problems, and as a result, have found a multi-stage polymer comprising a polypropylene resin having a specific long-chain branched structure, a specific propylene (co)polymer and a propylene-ethylene copolymer. By adjusting the combined propylene-based block copolymer, the propylene-α-olefin random copolymer component polymerized with a specific Ziegler-Natta catalyst, and the crystallization nucleating agent (K) at specific blending amounts Especially, even at a high expansion ratio of 3.0 times or more by the T-die foaming method, a foamed molded article having uniform and fine foamed cells, a good appearance of the molded article, and excellent heat deformation resistance can be obtained. and completed the present invention.

That is, according to the first aspect of the present invention, the polypropylene resin (X) having the following properties (Xi) to (Xiv) and having a long-chain branched structure is added at 67.5 to 2.5. 5 parts by weight, a multistage polymer having the following properties (Yi) to (Yv) and comprising a propylene (co)polymer (Y-1) and a propylene-ethylene copolymer (Y-2) 2.5 to 67.5 parts by weight of a propylene-based block copolymer (Y), which is a coalescence, and a propylene-α-olefin random copolymer having the following characteristics (Zi) to (Z-iii) A crystallization nucleating agent ( K) is provided in an amount of 0.01 to 1.0 parts by weight.
(Xi) MFR is 0.1 to 30.0 g/10 minutes.
(X-ii) The molecular weight distribution Mw/Mn measured by GPC is 3.0 to 10.0, and the Mz/Mw is 2.5 to 10.0.
(X-iii) Melt tension (MT) (unit: g) must satisfy either log(MT)≧−0.9×log(MFR)+0.7 or MT≧15.
(X-iv) The 25°C para-xylene soluble component content (CXS) is less than 5.0% by weight relative to the total weight of the polypropylene resin (X).
(Yi) The ratio of (Y-1) and (Y-2) is such that (Y-1) is 50 to 99% by weight and (Y-2) is 1 to 50% by weight (provided that propylene The total weight of the system block copolymer (Y) is 100% by weight).
(Y-ii) MFR of the propylene-based block copolymer (Y) is 0.1 to 200.0 g/10 minutes.
(Y-iii) The melting peak temperature of the propylene-based block copolymer (Y) exceeds 155°C.
(Y-iv) The ethylene content in the propylene-ethylene copolymer (Y-2) is 11 to 60% by weight (provided that the total weight of the constituent monomers of the propylene-ethylene copolymer (Y-2) is 100% by weight).
(Yv) The intrinsic viscosity of the propylene-ethylene copolymer (Y-2) in decalin at 135°C is 5.3 dl/g or more.
(Zi) Polymerized with a Ziegler-Natta catalyst.
(Z-ii) The melting peak temperature measured by DSC is 157° C. or lower.
(Z-iii) MFR is 21.0 g/10 minutes or more.

Further, according to the second invention of the present invention, there is provided a polypropylene resin composition characterized in that the polypropylene resin (X) in the first invention has the following characteristics (Xv) ( Xv): The branching index g ^' at an absolute molecular weight Mabs of 1,000,000 should be 0.30 or more and less than 0.95.

Furthermore, according to a third invention of the present invention, there is provided a polypropylene resin composition characterized in that the polypropylene resin (X) has the following properties (X-vi) in the second invention.
(X-vi): The mm fraction of 3 chains of propylene units determined by ¹³ C-NMR is 95% or more.

（式中、Ｒ^１は、直接結合、硫黄、炭素数１～９のアルキレン又は炭素数２～９のアルキリデンであり、Ｒ^２及びＲ^３は、同一又は異なって、それぞれ水素、炭素数１～８のアルキル又は炭素数７～９のアルキルアリールであり、ＭはＬｉ、Ｎａ、Ｋ、Ｍｇ、Ｃａ、Ｚｎ又はＡｌであり、ｎはＭの価数である。）

（式中、Ｒ^１は、水素又は炭素数１～４のアルキルであり、Ｒ^２及びＲ^３は、同一又は異なって、それぞれ水素又は炭素数１～１２のアルキルであり、Ｍは、周期表第１３族又は第１４族の金属であり、Ｘは、Ｍが周期表第１３族の金属である場合には、ＨＯ－であり、Ｍが周期表第１４族の金属である場合には、Ｏ＝又は（ＨＯ）_２－である。） According to a fourth invention of the present invention, in any one of the first to third inventions, the crystallization nucleating agent (K) is represented by the following general formulas (1) and (2). A polypropylene-based resin composition is provided.

(In the formula, R ¹ is a direct bond, sulfur, alkylene having 1 to 9 carbon atoms or alkylidene having 2 to 9 carbon atoms, and R ² and R ³ are the same or different and are each hydrogen, and 8 alkyl or C 7-9 alkylaryl, M is Li, Na, K, Mg, Ca, Zn or Al, and n is the valence of M.)

(In the formula, R ¹ is hydrogen or alkyl having 1 to 4 carbon atoms, R ² and R ³ are the same or different and each is hydrogen or alkyl having 1 to 12 carbon atoms, and M is the periodic table is a Group 13 or Group 14 metal, X is HO— if M is a Group 13 metal of the Periodic Table, and if M is a Group 14 metal of the Periodic Table, O= or (HO) ₂ -.)

（式中、ｎは、０～２の整数であり、Ｒ^１～Ｒ^５は、それぞれ独立して、同一又は異なって、水素、ハロゲン、炭素数１～２０のアルキル、炭素数２～２０のアルケニル、炭素数１～２０のアルコキシ、炭素数１～２０のアルコキシカルボニル又はフェニルであり、Ｒ^６は、炭素数１～２０のアルキルである。） Further, according to the fifth invention of the present invention, in any one of the first to third inventions, the crystallization nucleating agent (K) is represented by the following general formula (3). A resin composition is provided.

(In the formula, n is an integer of 0 to 2, and R ¹ to R ⁵ are each independently the same or different and are hydrogen, halogen, alkyl having 1 to 20 carbon atoms, alkenyl, alkoxy having 1 to 20 carbon atoms, alkoxycarbonyl having 1 to 20 carbon atoms or phenyl, and R ⁶ is alkyl having 1 to 20 carbon atoms.)

Further, according to the sixth invention of the present invention, in the polypropylene resin composition according to any one of the first to fifth inventions, 0.05 of a foaming agent is added to 100 parts by weight of the polypropylene resin mixture. There is provided a polypropylene-based resin composition for foam molding characterized by containing up to 6.0 parts by weight.

Moreover, according to the seventh invention of the present invention, there is provided a polypropylene resin foamed sheet characterized by extrusion molding of the polypropylene resin composition for foam molding according to the sixth invention.

Further, according to the eighth invention of the present invention, the polypropylene resin foam sheet according to the seventh invention and a non-foamed layer made of a thermoplastic resin composition are co-extruded. A resin multilayer foam sheet is provided.

Further, according to the ninth invention of the present invention, there is provided a molded article characterized by thermoforming the polypropylene resin foam sheet according to the seventh invention or the multilayer foam sheet according to the eighth invention. be done.

Further, according to the tenth invention of the present invention, the polypropylene resin composition according to any one of the first to fifth inventions or the polypropylene resin composition for foam molding according to the sixth invention is subjected to an injection molding method, Provided is a molded article characterized by being obtained by molding by any one of a thermoforming method, an extrusion molding method, a blow molding method and a bead foam molding method.

The polypropylene-based resin composition of the present invention has the characteristic that uniform fine foam cells can be obtained even under severe molding conditions, and in particular, in the foam sheet obtained by the T-die molding method, it is 3.0 times or more. Even at a high expansion ratio, uniform and fine foam cells can be obtained, so that a molded article having a good appearance and excellent heat deformation resistance can be obtained.
The resulting polypropylene-based resin (multilayer) foamed sheet and the thermoformed product using the same have excellent expansion ratio, uniform and fine foamed cells, excellent appearance, thermoformability, impact resistance, light weight, and rigidity. Due to its excellent heat resistance, heat resistance, oil resistance, etc., it is suitable for food containers such as trays, plates and cups, vehicle interior materials such as automobile door trims and automobile trunk mats, packaging, stationery, building materials, etc. be able to.

Embodiments of the present invention will be described in detail below. It is not limited to the described contents.

The polypropylene resin composition of the present invention (hereinafter sometimes referred to as "the resin composition of the present invention") has the following properties (Xi) to (Xiv) and has a long chain 67.5 to 2.5 parts by weight of a polypropylene resin (X) having a branched structure, a propylene (co)polymer (Y-1) having the following properties (Yi) to (Yv) 2.5 to 67.5 parts by weight of a propylene-based block copolymer (Y), which is a multistage polymer consisting of a propylene-ethylene copolymer (Y-2) and the following (Zi) to ( 100 parts by weight of a polypropylene-based resin mixture containing 10 to 75 parts by weight of a propylene-α-olefin random copolymer (Z) having the properties of Z-iii) (wherein (X), (Y), and (Z) The total amount is 100 parts by weight), and 0.01 to 1.0 parts by weight of the crystallization nucleating agent (K) is included. Further, the polypropylene resin composition for foam molding of the present invention is characterized by containing 0.05 to 6.0 parts by weight of a foaming agent with respect to 100 parts by weight of the polypropylene resin mixture.
The properties to be satisfied by the components (X), (Y), (Z) and the crystallization nucleating agent (K) are described below in detail for each item.

I. Polypropylene resin (X) having a long-chain branched structure
The polypropylene-based resin composition of the present invention is characterized by using a polypropylene resin (X) having the following properties (Xi) to (Xiv) and having a long-chain branched structure: do.
Property (Xi): MFR of 0.1 to 30.0 g/10 minutes.
Characteristic (X-ii): Molecular weight distribution Mw/Mn by GPC is 3.0 to 10.0 and Mz/Mw is 2.5 to 10.0.
Property (X-iii): Melt tension (MT) (unit: g)
log(MT)≧−0.9×log(MFR)+0.7 or MT≧15
satisfy any of
Characteristic (X-iv): 25°C para-xylene soluble component content (CXS) is less than 5.0% by weight with respect to the total weight of polypropylene resin (X).
Hereinafter, each characteristic requirement defined in the present invention, a method for producing the polypropylene resin (X) having a long-chain branched structure, and the like will be specifically described.

1. Characteristic (Xi): MFR
The melt flow rate (MFR) of the polypropylene resin (X) having a long-chain branched structure in the present invention must be in the range of 0.1-30.0 g/10 min, preferably 0.3-20. 0 g/10 min, more preferably 0.5 to 10.0 g/10 min. When the MFR of the polypropylene resin (X) is 0.1 g/10 min or more, problems such as excessive load on the extruder for various moldings due to insufficient fluidity are unlikely to occur. When it is less than 10 minutes, the tension is sufficient and the properties as a high melt tension material are good and suitable.
In addition, MFR is JIS K7210: 1999 "Plastics - Test methods for melt mass flow rate (MFR) and melt volume flow rate (MVR) of thermoplastics" Annex A Table 1, Condition M (230 ° C., 2.16 kg load), and the unit is g/10 minutes.

2. Characteristic (X-ii): Molecular weight distribution by GPC The polypropylene resin (X) having a long-chain branched structure must have a relatively wide molecular weight distribution, and the molecular weight obtained by gel permeation chromatography (GPC) The distribution Mw/Mn (where Mw is the weight average molecular weight and Mn is the number average molecular weight) must be 3.0 or more and 10.0 or less. The molecular weight distribution Mw/Mn of the polypropylene resin (X) having a long-chain branched structure is preferably 3.5 to 8.0, more preferably 4.1 to 6.0.
Furthermore, as a parameter that more remarkably expresses the width of the molecular weight distribution, Mz/Mw (where Mz is the Z-average molecular weight) must be 2.5 or more and 10.0 or less. A preferred range of Mz/Mw is 2.8 to 8.0, more preferably 3.0 to 6.0.
The broader the molecular weight distribution, the better the moldability, and those having Mw/Mn and Mz/Mw in this range are particularly excellent in moldability.
The definitions of Mn, Mw, and Mz are described in "Basics of Polymer Chemistry" (Kobunshi Gakkai ed., Tokyo Kagaku Dojin, 1978), etc., and can be calculated from the molecular weight distribution curve by GPC.

A specific measurement method of GPC is as follows.
・Apparatus: GPC manufactured by Waters (ALC/GPC 150C)
・ Detector: FOXBORO MIRAN 1A IR detector (measurement wavelength: 3.42 μm)
・Column: AD806M/S (three columns in series) manufactured by Showa Denko K.K.
・ Mobile phase solvent: ortho-dichlorobenzene (ODCB)
・Measurement temperature: 140°C
・Flow rate: 1.0 ml/min
・Injection volume: 0.2 ml
-Sample preparation: A 1 mg/mL solution of the sample is prepared using ODCB (containing 0.5 mg/mL of BHT) and dissolved at 140°C for about 1 hour.
Conversion from the retention volume obtained by GPC measurement to the molecular weight is carried out using a previously prepared standard polystyrene (PS) calibration curve. The standard polystyrene used is the following brand manufactured by Tosoh Corporation.
F380, F288, F128, F80, F40, F20, F10, F4, F1, A5000, A2500, A1000
A calibration curve is prepared by injecting 0.2 mL of a solution dissolved in ODCB (containing 0.5 mg/mL of BHT) so that each is 0.5 mg/mL. A calibration curve uses a cubic equation obtained by approximation using the least squares method.
The following numerical values are used for the viscosity formula [η]=K×M ^α used for conversion to molecular weight.
PS: K=1.38×10 ⁻⁴ , α=0.7
PP: K=1.03×10 ⁻⁴ , α=0.78

3. Property (X-iii): Melt Tension (MT)
Furthermore, the polypropylene resin (X) having a long-chain branched structure must satisfy the following condition (1).
・Condition (1)
log(MT)≧−0.9×log(MFR)+0.7
or MT≧15
satisfy at least one of
Here, MT is a capillograph 1B manufactured by Toyo Seiki Seisakusho Co., Ltd., capillary: diameter 2.0 mm, length 40 mm, cylinder diameter: 9.55 mm, cylinder extrusion speed: 20 mm / min, take-up speed: 4.0 m /min, temperature: 230 ° C., represents the melt tension when measured, the unit is gram. However, if the MT of component (X) is extremely high, the resin may break at a take-up speed of 4.0 m/min. Let MT be the tension at the speed of The measurement conditions and units of MFR are as described above.
This definition is an index for the polypropylene resin (X) having a long-chain branched structure to have sufficient melt tension for foam molding. It is described by a relational expression with
Thus, the method of defining MT by the relational expression with MFR is a normal method for those skilled in the art. is proposed.
log(MS)>−0.61×log(MFR)+0.82 (230° C.)
(Here, MS is synonymous with MT above.)
Further, Japanese Patent Application Laid-Open No. 2003-64193 proposes the following relational expression as a definition of polypropylene having high melt tension.
11.32×MFR ^−0.7854 ≦MT (230° C.)
Further, Japanese Patent Application Laid-Open No. 2003-94504 proposes the following relational expression as a definition of polypropylene having high melt tension.
MT≧7.52×MFR ^−0.576
(MT is a value measured at 190°C and MFR is a value measured at 230°C.)

If the polypropylene resin (X) having a long-chain branched structure satisfies the above condition (1), it can be said that the resin has a sufficiently high melt tension and is useful for foam molding. Moreover, it is more preferable to satisfy the following condition (1)', and it is even more preferable to satisfy the condition (1)''.
..Condition (1)'
log(MT)≧−0.9×log(MFR)+0.9
or MT≧15
satisfy at least one of
..Condition (1)”
log(MT)≧−0.9×log(MFR)+1.1
or MT≧15
satisfy at least one of
Although it is not necessary to set an upper limit for MT, when MT is 40 g or less, the take-up speed is not remarkably slowed by the above measurement method, and measurement becomes easy. In such a case, the spreadability of the resin is considered to be good, so the weight is preferably 40 g or less, more preferably 35 g or less, and most preferably 30 g or less.

4. Property (X-iv): 25°C para-xylene soluble component amount (CXS)
The polypropylene resin (X) having a long-chain branched structure used in the present invention preferably contains few low-crystalline components that cause stickiness and bleeding out when the product is produced. This low crystalline component is evaluated by the 25° C. xylene soluble content (CXS), which should be less than 5.0% by weight relative to the total weight of component (X), preferably It is 3.0% by weight or less, more preferably 1.0% by weight or less, and still more preferably 0.5% by weight or less. The lower limit is not particularly limited, but is usually 0.01% by weight or more, preferably 0.03% by weight or more. Details of the CXS measurement method are as follows.
After dissolving 2 g of the sample in 300 ml of p-xylene (containing 0.5 mg/ml of BHT) at 130° C. to form a solution, the solution is allowed to stand at 25° C. for 12 hours. Thereafter, the precipitated polymer is filtered off, p-xylene is evaporated from the filtrate, and the residue is dried under reduced pressure at 100° C. for 12 hours to recover xylene-soluble components at room temperature. The ratio [% by weight] of the weight of the recovered component to the weight of the charged sample is defined as CXS.

Additional characteristics of the polypropylene resin (X) having a long-chain branched structure used in the present invention include the following properties (Xv) to (Xvi).

5. Property (Xv): branching index g'
A branching index g ^' can be given as a direct indicator that the polypropylene resin (X) having a long-chain branched structure has a long-chain branched structure. g ^′ is given by the ratio of the intrinsic viscosity [η]br of a polymer with a long chain branched structure to the intrinsic viscosity [η]lin of a linear polymer with the same molecular weight, i.e., [η]br/[η]lin , takes a value less than 1 if long-chain branched structures are present.
The definition of the branching index g' is described, for example, in "Developments in Polymer Characterization-4" (J.V. Dawkins ed. Applied Science Publishers, 1983), and is an index known to those skilled in the art.

g ^′ can be obtained as a function of absolute molecular weight Mabs, for example, by using GPC with a light scatterometer and viscometer detector as described below.
The polypropylene resin (X) having a long-chain branched structure used in the present invention preferably has a g′ of 0.30 or more and less than 0.95 when the absolute molecular weight Mabs obtained by light scattering is 1,000,000. It is preferably 0.55 or more and less than 0.95, more preferably 0.75 or more and less than 0.95, and most preferably 0.78 or more and less than 0.95.
As described in detail below, the polypropylene resin (X) having a long-chain branched structure used in the present invention is considered to have a comb-shaped chain as a molecular structure from its polymerization mechanism, and g′ is 0.30 or more. In this case, the proportion of the main chain is small and the proportion of the side chain is not extremely large. In such a case, the melt tension is improved and there is no possibility of gel formation, which is preferable in foam molding. On the other hand, when g' is less than 0.95, branches are present, so the melt tension tends not to be insufficient, which is suitable for foam molding.

The reason why it is preferable that the lower limit of g' is the above value is as follows.
According to "Encyclopedia of Polymer Science and Engineering vol.2" (John Wiley & Sons 1985 p.485), the g ^' value of comb polymer is expressed by the following formula.

Here, g is a branching index defined by the radius of gyration ratio of the polymer, and ε is a constant determined by the shape of the branched chain and the solvent. According to Table 3 of 487, a value of about 0.7 to 1.0 is reported for comb-shaped chains in a good solvent. λ is the proportion of the main chain in the comb chain and p is the average number of branches. According to this formula, a comb-shaped chain would have a very large number of branches, i.e., in the limit of p being infinite, g ^′ =g ^ε =λ ^ε and would not fall below the value of λ ^ε . , there will generally be a lower bound.
On the other hand, the conventionally known formula for random branching, which is thought to occur in the case of electron beam irradiation or peroxide modification, is given in formula (19) on page 485 of the same document, according to which random branching In a chain, the g' and g values decrease monotonically as the number of branch points increases, with no particular lower limit. That is, in the present invention, the fact that the g' value has a lower limit means that the polypropylene resin (X) having a long-chain branched structure used in the present invention has a structure close to a comb-shaped chain. This makes it clearer to distinguish them from random branched chains generated by electron beam irradiation or peroxide modification.
In addition, in a branched polymer having a structure close to a comb-shaped chain in which g′ is within the above range, the degree of decrease in the melt tension when kneading is repeated is small, and it occurs in the process of industrially producing a molded product. For example, remnants generated by cutting the ends during sheet or film molding, or parts such as injection molding runners, can be reused as recycled materials for molding, resulting in less deterioration in physical properties and moldability. ,preferable.

A specific method for calculating g' is as follows.
As a GPC apparatus equipped with a differential refractometer (RI) and a viscosity detector (Viscometer), Alliance GPCV2000 manufactured by Waters Co. is used. As a light scattering detector, a multi-angle laser light scattering detector (MALLS) DAWN-E manufactured by Wyatt Technology is used. The detectors are connected in the order MALLS, RI, Viscometer. The mobile phase solvent is 1,2,4-trichlorobenzene (antioxidant Irganox 1076 manufactured by BASF Japan Co., Ltd. added at a concentration of 0.5 mg/mL).
The flow rate is 1 mL/min, and two Tosoh GMHHR-H(S) HT columns are used. The temperature of the column, sample injection part and each detector is 140°C. The sample concentration is 1 mg/mL and the injection volume (sample loop volume) is 0.2175 mL.
The data processing software ASTRA (version 4.73.04) attached to MALLS is used to determine the absolute molecular weight (Mabs), the root mean square radius of inertia (Rg) obtained from MALLS, and the intrinsic viscosity ([η]) obtained from Viscometer. Calculations are performed with reference to the following literature.
References:
1. "Developments in Polymer Characterization-4" (JV Dawkins ed. Applied Science Publishers, 1983. Chapter 1.)
2. Polymer, 45, 6495-6505 (2004)
3. Macromolecules, 33, 2424-2436 (2000)
4. Macromolecules, 33, 6945-6952 (2000)

[Calculation of branching index (g')]
The branching index (g′) is the ratio of the intrinsic viscosity ([η] br) obtained by measuring the sample with the Viscometer and the intrinsic viscosity ([η] lin) obtained by separately measuring the linear polymer. It is calculated as ([η]br/[η]lin).
When a long-chain branched structure is introduced into a polymer molecule, the radius of gyration becomes smaller than that of a linear polymer molecule of the same molecular weight. Since the intrinsic viscosity decreases as the radius of inertia decreases, the intrinsic viscosity ([η] br) of the branched polymer relative to the intrinsic viscosity ([η] lin) of the linear polymer with the same molecular weight as the long-chain branched structure is introduced The ratio of ([η]br/[η]lin) becomes smaller.
Therefore, if the branching index (g'=[η]br/[η]lin) is less than 1.0, it means that branching has been introduced. Here, as a linear polymer for obtaining [η]lin, commercially available homopolypropylene (Novatec PP (registered trademark) manufactured by Japan Polypropylene Corporation, grade name: FY6) is used. It is known as the Mark-Houwink-Sakurada formula that the logarithm of [η]lin of a linear polymer has a linear relationship with the logarithm of the molecular weight. A numerical value can be obtained by extrapolation.

6. Characteristic (X-vi): mm fraction of propylene unit triplets by ¹³ C-NMR The polypropylene resin (X) having a long-chain branched structure used in the present invention preferably has high stereoregularity. The degree of stereoregularity can be evaluated by ¹³ C-NMR, and those having a stereoregularity of 95.0% or more in mm fraction of propylene unit tricycles obtained by ¹³ C-NMR are preferable.
The mm fraction is the ratio of 3 chains of propylene units having the same methyl branch direction in each propylene unit among arbitrary 3 chains of propylene units consisting of head-to-tail bonds in the polymer chain, and the upper limit is 100%. is. This mm fraction is a value indicating that the steric structure of the methyl groups in the polypropylene molecular chain is isotactically controlled, and the higher the value, the more highly controlled it is. If the mm fraction is less than this value, the product tends to have poor mechanical properties such as low elastic modulus.
Therefore, the mm fraction is preferably 95.0% or more, more preferably 96.0% or more, still more preferably 97.0% or more. In addition, both the properties (X-iv) and (X-vi) are properties related to stereoregularity, and it is particularly preferable that the requirements of the properties (X-iv) and (X-vi) are satisfied at the same time. .

The details of the method for measuring the mm fraction of 3 chains of propylene units by ¹³ C-NMR are as follows.
After completely dissolving 375 mg of a sample in 2.5 ml of deuterated 1,1,2,2-tetrachloroethane in an NMR sample tube (10φ), it is measured at 125°C by the proton complete decoupling method. Chemical shifts set the middle peak of the three peaks for deuterated 1,1,2,2-tetrachloroethane at 74.2 ppm. Chemical shifts of other carbon peaks are based on this.
Flip angle: 90 degrees Pulse interval: 10 seconds Resonance frequency: 100 MHz or more Accumulation times: 10,000 times or more Observation range: -20 ppm to 179 ppm
Number of data points: 32768
Analysis of the mm fraction is performed using the ¹³ C-NMR spectrum measured under the conditions described above.
Spectral assignment is performed with reference to Macromolecules, (1975), Volume 8, page 687 and Polymer, Vol. 30, p. 1350 (1989).
A more specific method for determining the mm fraction is described in detail in paragraphs [0053] to [0065] of JP-A-2009-275207, and this method is also used in the present specification. do.
In the present invention, the property (X-iii) satisfies log (MT) ≥ -0.9 × log (MFR) + 0.7, and Mabs is 1 million, g'< 1 satisfying the long-chain It can be said that it has a branched structure.

7. Characteristics: Blending amount of polypropylene resin (X) having a long chain branched structure The blended amount of the polypropylene resin (X) having a long chain branched structure is 67.5 to 2.5 parts by weight, preferably 60.0 to 10.0 parts by weight. 0 parts by weight, more preferably 55.0 to 15.0 parts by weight, more preferably 52.5 to 17.5 parts by weight (provided that the total of (X), (Y), and (Z) is 100 parts by weight part). When the amount of the polypropylene resin (X) having a long-chain branched structure is within this range, shear heat generation can be achieved even at high speed molding by the T-die method and at a high expansion ratio exceeding 3.0 times. It is possible to reduce the load on the sheet due to the tension and the take-up tension, and it is possible to obtain a foamed sheet which is excellent in the independence of cells and the denseness, and which has a high appearance. Also, when the blending amount is 67.5 parts by weight or less, the fluidity is sufficient, and there is no problem that the load on the extruder is too high for various moldings. , the melt tension becomes sufficient, the properties as a high melt tension material are excellent, and the material is suitable for foam molding.

8. Method for Producing Polypropylene Resin (X) Having Long-Chain Branched Structure The polypropylene resin (X) having a long-chain branched structure is the above-described (Xi) to (Xiv), and preferably (Xv). Although the production method is not particularly limited as long as the properties of ~ (X-vi) are satisfied, as described above, high stereoregularity, low amount of low-crystalline components, relatively wide molecular weight distribution, branching index g ^' range, high melt tension, etc., a preferred manufacturing method is a method using a macromer copolymerization method utilizing a combination of metallocene catalysts. An example of such a method is the method disclosed in Japanese Unexamined Patent Application Publication No. 2009-57542.
This method uses a catalyst that combines a catalyst component with a specific structure capable of producing macromers and a catalyst component with a specific structure that has high molecular weight and macromer copolymerization capabilities to produce polypropylene with a long-chain branched structure. According to this method, it is an industrially effective method such as a bulk polymerization method or a gas phase polymerization method, especially a single-stage polymerization under practical pressure and temperature conditions, and hydrogen as a molecular weight modifier is used. It is possible to produce a polypropylene resin having a long-chain branched structure with the desired physical properties.
Conventionally, the efficiency of branch formation had to be increased by using a polypropylene component with low stereoregularity to lower the crystallinity. , It is possible to introduce it into the side chain by a simple method, and it is preferable as the polypropylene resin (X) used in the present invention, which has high stereoregularity and a low low crystalline component amount (X-vi) and (X It is suitable for satisfying the characteristics of -iv).
In addition, by using the above method, it is possible to widen the molecular weight distribution by using two kinds of catalysts with greatly different polymerization characteristics, and the (X- Characteristics i) to (X-iii) can be satisfied at the same time, which is preferable.

Therefore, a preferred method for producing the polypropylene resin (X) having a long-chain branched structure used in the present invention is described in detail below.
A preferred method for producing the polypropylene resin (X) having a long-chain branched structure is a method for producing a propylene-based polymer using the following catalyst components (A), (B) and (C) as a propylene polymerization catalyst.
(A): At least one component selected from component [A-1], which is a compound represented by the following general formula (a1), and at least one component selected from component [A-2], which is a compound represented by the following general formula (a2) Two or more transition metal compounds of Group 4 of the periodic table, one of which is selected.
Component [A-1]: compound represented by general formula (a1) Component [A-2]: compound represented by general formula (a2) (B): ion-exchange layered silicate (C): organic aluminum Compound

The catalyst components (A), (B) and (C) are described in detail below.
(1) Catalyst component (A)
(i) Component [A-1]: a compound represented by general formula (a1)

In general formula (a1), R ¹¹ and R ¹² each independently represents a heterocyclic group containing 4 to 16 carbon atoms, nitrogen, oxygen, or sulfur. R ¹³ and R ¹⁴ are each independently halogen, silicon, oxygen, sulfur, nitrogen, boron, phosphorus, or aryl having 6 to 16 carbon atoms which may contain a plurality of hetero elements selected from these group, nitrogen or oxygen of 6 to 16 carbon atoms, heterocyclic group containing sulfur. Furthermore, X ¹¹ and Y ¹¹ each independently represent a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing hydrocarbon group having 1 to 20 carbon atoms, a halogenated group having 1 to 20 carbon atoms, represents a hydrocarbon group, an oxygen-containing hydrocarbon group having 1 to 20 carbon atoms, an amino group or a nitrogen-containing hydrocarbon group having 1 to 20 carbon atoms, Q ¹¹ is a divalent hydrocarbon group having 1 to 20 carbon atoms, It represents a silylene group or a germylene group optionally having a hydrocarbon group of 1 to 20 carbon atoms.

The heterocyclic group containing 4 to 16 carbon atoms, oxygen, or sulfur for R ¹¹ and R ¹² is preferably a 2-furyl group, a substituted 2-furyl group, a substituted 2-thienyl group, It is a substituted 2-furfuryl group, more preferably a substituted 2-furyl group.
Further, substituted 2-furyl group, substituted 2-thienyl group and substituted 2-furfuryl group include alkyl groups having 1 to 6 carbon atoms such as methyl group, ethyl group and propyl group, Examples include halogen atoms such as fluorine and chlorine atoms, alkoxy groups having 1 to 6 carbon atoms such as methoxy and ethoxy groups, and trialkylsilyl groups. Among these, a methyl group and a trimethylsilyl group are preferred, and a methyl group is particularly preferred.
Furthermore, 2-(5-methyl)-furyl group is particularly preferred as R ¹¹ and R ¹² . Also, R ¹¹ and R ¹² are preferably the same as each other.
As the aryl group having 6 to 16 carbon atoms of R ¹³ and R ¹⁴ and which may contain a plurality of hetero elements selected from halogen, silicon, oxygen, sulfur, nitrogen, boron, phosphorus, or these, Within the range of 6 to 16 carbon atoms, one or more hydrocarbon groups having 1 to 6 carbon atoms, silicon-containing hydrocarbon groups having 1 to 6 carbon atoms, and halogen having 1 to 6 carbon atoms are added to the aryl cyclic skeleton. You may have the containing hydrocarbon group as a substituent.

At least one of R ¹³ and R ¹⁴ is preferably a phenyl group, 4-methylphenyl group, 4-i-propylphenyl group, 4-t-butylphenyl group, 4-trimethylsilylphenyl group, 2,3-dimethyl phenyl group, 3,5-di-t-butylphenyl group, 4-phenyl-phenyl group, chlorophenyl group, naphthyl group or phenanthryl group, more preferably phenyl group, 4-i-propylphenyl group, 4- t-butylphenyl group, 4-trimethylsilylphenyl group, and 4-chlorophenyl group. It is also preferred if R ¹³ and R ¹⁴ are the same as each other.

In general formula (a1), X ¹¹ and Y ¹¹ are ancillary ligands that react with the cocatalyst of the catalyst component (B) to produce an active metallocene capable of olefin polymerization. Therefore, as long as this object is achieved, the types of ligands of X ¹¹ and Y ¹¹ are not limited, and each independently represents a hydrogen atom, a halogen atom, or a hydrocarbon group having 1 to 20 carbon atoms. , a silicon-containing hydrocarbon group having 1 to 20 carbon atoms, a halogenated hydrocarbon group having 1 to 20 carbon atoms, an oxygen-containing hydrocarbon group having 1 to 20 carbon atoms, an amino group, or a nitrogen-containing hydrocarbon group having 1 to 20 carbon atoms alkoxy group having 1 to 20 carbon atoms, alkylamide group having 1 to 20 carbon atoms, trifluoromethanesulfonic acid group, and phosphorus-containing hydrocarbon group having 1 to 20 carbon atoms.

In the general formula (a1), Q ¹¹ is a divalent hydrocarbon group having 1 to 20 carbon atoms and a silylene optionally having a hydrocarbon group having 1 to 20 carbon atoms, which binds two five-membered rings. or germylene groups. When two hydrocarbon groups are present on the silylene group or germylene group described above, they may bond together to form a ring structure.
Specific examples of Q ¹¹ above include alkylene groups such as methylene, methylmethylene, dimethylmethylene, 1,2-ethylene; arylalkylene groups such as diphenylmethylene; silylene groups; Alkylsilylene groups such as (n-propyl)silylene, di(i-propyl)silylene, and di(cyclohexyl)silylene; (alkyl)(aryl)silylene groups such as methyl(phenyl)silylene; arylsilylene groups such as diphenylsilylene; Alkyloligosilylene groups such as tetramethyldisilylene; germylene groups; alkylgermylene groups obtained by substituting germanium for silicon in the silylene group having a divalent hydrocarbon group having 1 to 20 carbon atoms; (alkyl) (aryl) A germylene group; an arylgermylene group and the like can be mentioned. Among these, a silylene group having a hydrocarbon group of 1 to 20 carbon atoms or a germylene group having a hydrocarbon group of 1 to 20 carbon atoms is preferable, and an alkylsilylene group and an alkylgermylene group are particularly preferable.

Among the compounds represented by the general formula (a1), preferred compounds are specifically exemplified below.
Dichloro[1,1'-dimethylsilylenebis{2-(2-furyl)-4-phenyl-indenyl}]hafnium, dichloro[1,1'-dimethylsilylenebis{2-(2-thienyl)-4-phenyl -indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-(5-methyl-2-furyl)-4-phenyl-indenyl}]hafnium, dichloro[1,1′-diphenylsilylenebis{2 -(5-methyl-2-furyl)-4-phenyl-indenyl}]hafnium, dichloro[1,1′-dimethylgermylenebis{2-(5-methyl-2-furyl)-4-phenyl-indenyl} ] Hafnium, dichloro[1,1′-dimethylgermylenebis{2-(5-methyl-2-thienyl)-4-phenyl-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-( 5-t-butyl-2-furyl)-4-phenyl-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-(5-trimethylsilyl-2-furyl)-4-phenyl-indenyl}] Hafnium, dichloro[1,1′-dimethylsilylenebis{2-(5-phenyl-2-furyl)-4-phenyl-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-(4, 5-dimethyl-2-furyl)-4-phenyl-indenyl}]hafnium dichloride, dichloro[1,1′-dimethylsilylenebis{2-(2-benzofuryl)-4-phenyl-indenyl}]hafnium, dichloro[1 ,1′-dimethylsilylenebis{2-(5-methyl-2-furyl)-4-(4-methylphenyl)-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-(5- methyl-2-furyl)-4-(4-ipropylphenyl)-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-(5-methyl-2-furyl)-4-(4- trimethylsilylphenyl)-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-(2-furfuryl)-4-phenyl-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2- (5-methyl-2-furyl)-4-(4-chlorophenyl)-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-(5-methyl-2-furyl)-4-(4 -fluorophenyl)-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-(5-methyl-2-furyl)-4-(4-trifluoromethylphenyl)-indenyl}]hafnium, dichloro [1,1′-dimethylsilylenebis{2-(5-methyl-2-furyl)-4-(4-t-butylphenyl)-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2 -(2-furyl)-4-(1-naphthyl)-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-(2-furyl)-4-(2-naphthyl)-indenyl}] Hafnium, dichloro[1,1′-dimethylsilylenebis{2-(2-furyl)-4-(2-phenanthryl)-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-(2- furyl)-4-(9-phenanthryl)-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-(5-methyl-2-furyl)-4-(1-naphthyl)-indenyl}] Hafnium, dichloro[1,1'-dimethylsilylenebis{2-(5-methyl-2-furyl)-4-(2-naphthyl)-indenyl}]hafnium, dichloro[1,1'-dimethylsilylenebis{2 -(5-methyl-2-furyl)-4-(2-phenanthryl)-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-(5-methyl-2-furyl)-4-( 9-Phenanthryl)-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-(5-t-butyl-2-furyl)-4-(1-naphthyl)-indenyl}]hafnium, dichloro[ 1,1′-dimethylsilylenebis{2-(5-t-butyl-2-furyl)-4-(2-naphthyl)-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-( 5-t-butyl-2-furyl)-4-(2-phenanthryl)-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-(5-t-butyl-2-furyl)-4 -(9-phenanthryl)-indenyl}]hafnium, and the like.

Among these, more preferred are dichloro[1,1′-dimethylsilylenebis{2-(5-methyl-2-furyl)-4-phenyl-indenyl}]hafnium, dichloro[1,1′-dimethylsilylene Bis{2-(5-methyl-2-furyl)-4-(4-methylphenyl)-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-(5-methyl-2-furyl) -4-(4-ipropylphenyl)-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-(5-methyl-2-furyl)-4-(4-trimethylsilylphenyl)-indenyl} ] Hafnium, dichloro[1,1′-dimethylsilylenebis{2-(5-methyl-2-furyl)-4-(4-chlorophenyl)-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{ 2-(5-methyl-2-furyl)-4-(2-naphthyl)-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-(5-methyl-2-furyl)-4- (4-t-butylphenyl)-indenyl}]hafnium.
Also particularly preferred are dichloro[1,1′-dimethylsilylenebis{2-(5-methyl-2-furyl)-4-phenyl-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{ 2-(5-methyl-2-furyl)-4-(4-ipropylphenyl)-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-(5-methyl-2-furyl)- 4-(4-trimethylsilylphenyl)-indenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-(5-methyl-2-furyl)-4-(4-t-butylphenyl)-indenyl} ] hafnium.

(ii) component [A-2]: a compound represented by general formula (a2)

In general formula (a2), R ²¹ and R ²² are each independently a hydrocarbon group having 1 to 6 carbon atoms, R ²³ and R ²⁴ are each independently halogen, silicon, oxygen, sulfur , nitrogen, boron, phosphorus or an aryl group having 6 to 16 carbon atoms which may contain a plurality of hetero elements selected from these. X ²¹ and Y ²¹ are each independently a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing hydrocarbon group having 1 to 20 carbon atoms, or a halogenated hydrocarbon group having 1 to 20 carbon atoms. group, an oxygen-containing hydrocarbon group having 1 to 20 carbon atoms, an amino group or a nitrogen-containing hydrocarbon group having 1 to 20 carbon atoms, Q ²¹ is a divalent hydrocarbon group having 1 to 20 carbon atoms, represents a silylene or germylene group optionally having 1 to 20 hydrocarbon groups. ^M21 is zirconium or hafnium.

R ²¹ and R ²² above are each independently a hydrocarbon group having 1 to 6 carbon atoms, preferably an alkyl group, more preferably an alkyl group having 1 to 4 carbon atoms. Specific examples include methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl, n-pentyl, i-pentyl, n-hexyl and the like, preferably methyl , ethyl, and n-propyl.

In addition, R ²³ and R ²⁴ each independently contain a halogen having 6 to 16 carbon atoms, preferably 6 to 12 carbon atoms, silicon, or a plurality of hetero elements selected from these. is a good aryl group. Preferred examples are phenyl, 3-chlorophenyl, 4-chlorophenyl, 3-fluorophenyl, 4-fluorophenyl, 4-methylphenyl, 4-i-propylphenyl, 4-t-butylphenyl, 4-trimethylsilylphenyl, 4- (2-fluoro-4-biphenylyl), 4-(2-chloro-4-biphenylyl), 1-naphthyl, 2-naphthyl, 4-chloro-2-naphthyl, 3-methyl-4-trimethylsilylphenyl, 3,5 -dimethyl-4-t-butylphenyl, 3,5-dimethyl-4-trimethylsilylphenyl, 3,5-dichloro-4-trimethylsilylphenyl and the like.

X ²¹ and Y ²¹ are ancillary ligands and react with the cocatalyst of the catalyst component (B) to produce an active metallocene capable of olefin polymerization. Therefore, the types of ligands of X ²¹ and Y ²¹ are not limited as long as this object is achieved, and each independently represents a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing hydrocarbon group having 1 to 20 carbon atoms, a halogenated hydrocarbon group having 1 to 20 carbon atoms, an oxygen-containing hydrocarbon group having 1 to 20 carbon atoms, an amino group, or a nitrogen-containing hydrocarbon group having 1 to 20 carbon atoms , an alkoxy group having 1 to 20 carbon atoms, an alkylamide group having 1 to 20 carbon atoms, a trifluoromethanesulfonic acid group, and a phosphorus-containing hydrocarbon group having 1 to 20 carbon atoms.

In addition, the above Q ²¹ is a bonding group that bridges two conjugated five-membered ring ligands and has a divalent hydrocarbon group with 1 to 20 carbon atoms and a hydrocarbon group with 1 to 20 carbon atoms. or a germylene group having a hydrocarbon group of 1 to 20 carbon atoms, preferably a substituted silylene group or a substituted germylene group.

The substituents bonded to silicon and germanium are preferably hydrocarbon groups having 1 to 12 carbon atoms, and two substituents may be linked. Specific examples include methylene, dimethylmethylene, ethylene-1,2-diyl, dimethylsilylene, diethylsilylene, diphenylsilylene, methylphenylsilylene, 9-silafluorene-9,9-diyl, dimethylsilylene, diethylsilylene, diphenylsilylene, methylphenylsilylene, 9-silafluorene-9,9-diyl, dimethylgermylene, diethylgermylene, diphenylgermylene, methylphenylgermylene and the like.

Further, ^M21 is zirconium or hafnium, preferably hafnium.

Non-limiting examples of the metallocene compound represented by the general formula (a2) include the following.
However, the following describes only representative exemplary compounds to avoid a large number of complicated examples, and the present invention is not to be interpreted as being limited to these compounds, and various ligands, cross-linking groups, or auxiliary It is self-evident that any ligand can be used. In addition, although compounds in which the central metal is hafnium have been described, compounds in which zirconium is substituted are also treated as those disclosed in this specification.

Dichloro{1,1′-dimethylsilylenebis(2-methyl-4-phenyl-4-hydroazulenyl)}hafnium, dichloro[1,1′-dimethylsilylenebis{2-methyl-4-(4-chlorophenyl)-4 -hydroazulenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-methyl-4-(4-t-butylphenyl)-4-hydroazulenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{ 2-methyl-4-(4-trimethylsilylphenyl)-4-hydroazulenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-methyl-4-(3-chloro-4-t-butylphenyl)- 4-hydroazulenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-methyl-4-(3-methyl-4-t-butylphenyl)-4-hydroazulenyl}]hafnium, dichloro[1,1′ -dimethylsilylenebis{2-methyl-4-(3-chloro-4-trimethylsilylphenyl)-4-hydroazulenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-methyl-4-(3-methyl -4-trimethylsilylphenyl)-4-hydroazulenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-methyl-4-(1-naphthyl)-4-hydroazulenyl}]hafnium, dichloro[1,1′ -dimethylsilylenebis{2-methyl-4-(2-naphthyl)-4-hydroazulenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-methyl-4-(4-chloro-2-naphthyl) -4-hydroazulenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-methyl-4-(2-fluoro-4-biphenylyl)-4-hydroazulenyl}]hafnium, dichloro[1,1′-dimethyl Silylenebis{2-methyl-4-(2-chloro-4-biphenylyl)-4-hydroazulenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-methyl-4-(9-phenanthryl)-4 -hydroazulenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-ethyl-4-(4-chlorophenyl)-4-hydroazulenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-n -propyl-4-(3-chloro-4-trimethylsilylphenyl)-4-hydroazulenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-ethyl-4-(3-chloro-4-t-butyl Phenyl)-4-hydroazulenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-ethyl-4-(3-methyl-4-trimethylsilylphenyl)-4-hydroazulenyl}]hafnium, dichloro[1,1 '-dimethylgermylenebis{2-methyl-4-(2-fluoro-4-biphenylyl)-4-hydroazulenyl}]hafnium, dichloro[1,1'-dimethylgermylenebis{2-methyl-4-(4 -t-butylphenyl)-4-hydroazulenyl}]hafnium, dichloro[1,1′-(9-silafluorene-9,9-diyl)bis{2-ethyl-4-(4-chlorophenyl)-4-hydroazulenyl }] hafnium, dichloro[1,1′-dimethylsilylenebis{2-ethyl-4-(4-chloro-2-naphthyl)-4-hydroazulenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2 -ethyl-4-(2-fluoro-4-biphenylyl)-4-hydroazulenyl}]hafnium, dichloro[1,1′-(9-silafluorene-9,9-diyl)bis{2-ethyl-4-( 3,5-dichloro-4-trimethylsilylphenyl)-4-hydroazulenyl}]hafnium, and the like.

Among these, dichloro[1,1′-dimethylsilylenebis{2-methyl-4-(4-chlorophenyl)-4-hydroazulenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2- Methyl-4-(3-chloro-4-trimethylsilylphenyl)-4-hydroazulenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-ethyl-4-(2-fluoro-4-biphenylyl)-4 -hydroazulenyl}]hafnium, dichloro[1,1'-dimethylsilylenebis{2-ethyl-4-(4-chloro-2-naphthyl)-4-hydroazulenyl}]hafnium, dichloro[1,1'-dimethylsilylenebis {2-ethyl-4-(3-methyl-4-trimethylsilylphenyl)-4-hydroazulenyl}]hafnium, dichloro[1,1′-(9-silafluorene-9,9-diyl)bis{2-ethyl- 4-(3,5-dichloro-4-trimethylsilylphenyl)-4-hydroazulenyl}]hafnium.

Also, particularly preferably, dichloro[1,1′-dimethylsilylenebis{2-methyl-4-(4-chlorophenyl)-4-hydroazulenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-ethyl -4-(2-fluoro-4-biphenylyl)-4-hydroazulenyl}]hafnium, dichloro[1,1′-dimethylsilylenebis{2-ethyl-4-(3-methyl-4-trimethylsilylphenyl)-4- hydroazulenyl}]hafnium, dichloro[1,1′-(9-silafluorene-9,9-diyl)bis{2-ethyl-4-(3,5-dichloro-4-trimethylsilylphenyl)-4-hydroazulenyl}] Hafnium.

(2) catalyst component (B)
The catalyst component (B) preferably used for producing the polypropylene resin (X) is an ion-exchange layered silicate.
(i) Types of ion-exchangeable phyllosilicates Ion-exchangeable phyllosilicates (hereinafter sometimes simply abbreviated as silicates) are those in which planes formed by ionic bonds and the like are stacked in parallel with each other by bonding force. A silicate compound that has a crystalline structure and contains exchangeable ions. Since most silicates are naturally produced as the main component of clay minerals, they often contain contaminants (quartz, cristobalite, etc.) other than ion-exchanged layered silicates. It's okay. Depending on the type, amount, particle size, crystallinity and dispersion state of these contaminants, they may be more preferable than pure silicate, and such composites are also included in the catalyst component (B).
The silicate used in the present invention is not limited to naturally-occurring silicates, and may be artificially synthesized silicates, or may contain them.

Specific examples of silicates include the following layered silicates described in Haruo Shiramizu, Clay Mineralogy, Asakura Shoten (1995).
That is, smectites such as montmorillonite, sauconite, beidellite, nontronite, saponite, hectorite and stevensite; vermiculites such as vermiculite; mica such as mica, illite, sericite and glauconite; , bentonite, pyrophyllite, talc, chlorite group, etc.
The silicate is preferably a silicate having a 2:1 type structure as the main component, more preferably a smectite group, and particularly preferably montmorillonite. Although the type of interlayer cation is not particularly limited, silicates containing an alkali metal or an alkaline earth metal as a main component of the interlayer cation are preferred from the viewpoint of being relatively easily available as an industrial raw material at a low cost.

(ii) Chemical treatment of ion-exchangeable layered silicate Although the ion-exchanged layered silicate of the catalyst component (B) according to the present invention can be used as it is without any particular treatment, it is preferable to perform a chemical treatment. . Here, the chemical treatment of the ion-exchange layered silicate can be either a surface treatment for removing impurities adhering to the surface or a treatment for affecting the structure of the clay. treatment, alkali treatment, salt treatment, organic matter treatment, and the like.

<Acid treatment>:
The acid treatment removes impurities on the surface and also dissolves some or all of the cations such as Al, Fe, Mg, etc. in the crystal structure.
The acid used in the acid treatment is preferably selected from hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, acetic acid and oxalic acid.
Two or more kinds of salts (explained in the next section) and acids may be used for the treatment. The conditions for the treatment with salts and acids are not particularly limited, but usually the concentration of salts and acids is 0.1 to 50% by weight, the treatment temperature is from room temperature to the boiling point, and the treatment time is from 5 minutes to 24 hours. It is preferable to select conditions under which at least a portion of the substance constituting at least one compound selected from the group consisting of ion-exchangeable layered silicates is eluted. Salts and acids are also generally used in aqueous solution.
In addition, you may use the thing which combined the following acids and salts as a processing agent. A combination of these acids and salts may also be used.

<Salt treatment>:
40% or more, preferably 60% or more of the exchangeable group 1 metal cations contained in the ion-exchangeable layered silicate before being treated with salts are cations dissociated from the salts shown below. , preferably ion-exchanged.
Salts used in salt treatment for the purpose of such ion exchange include cations containing at least one atom selected from the group consisting of Groups 1 to 14 of the periodic table, halogen atoms, inorganic acids and organic acids. and at least one anion selected from the group consisting of, more preferably a cation containing at least one atom selected from the group consisting of Groups 2 to 14 of the periodic table and Cl, Br, I , F, _{PO4 , SO4} , _NO3 , CO3 _{, C2O4} , _{ClO4 , OOCCH3} , _CH3COCHCOCH3 , _OCl2 , O(NO3) ₂ , O( _ClO4 ) _{2 ,} O( SO ₄ ), OH, O ₂ Cl ₂ , OCl ₃ , OOCH, OOCCH ₂ CH ₃ , C ₂ H ₄ O ₄ and at least one anion selected from the group consisting of C ₅ H ₅ O ₇ . be.

Specific examples _of such _salts include LiF, LiCl, LiBr, LiI, _Li2SO4 , Li( _CH3COO ), _LiCO3 , Li( _{C6H5O7 )} , _LiCHO2 , _{LiC2O4 .} , _LiClO4 , _{Li3PO4 , CaCl2} , _CaSO4 , _CaC2O4 , Ca( _NO3 ) ₂ , _Ca3 ( _{C6H5O7 ) 2 , MgCl2} , _MgBr2 , _{MgSO4 ,} Mg( PO ₄ ) ₂ , Mg(ClO ₄ ) ₂ , MgC ₂ O ₄ , Mg(NO ₃ ) ₂ , Mg(OOCCH ₃ ) ₂ , MgC ₄ H ₄ O ₄ and the like.

In addition, Ti( _OOCCH3 ) ₄ , Ti( _CO3 ) ₂ , Ti( _NO3 ) ₄ , Ti( _SO4 ) ₂ , TiF4 _{, TiCl4} , Zr( _OOCCH3 ) ₄ , Zr( _CO3 ) ₂ , Zr( _NO3 ) ₄ , Zr( _SO4 ) ₂ , _ZrF4 , _ZrCl4 , ZrOCl2, ZrO( _NO3 ) ₂ , ZrO( _ClO4 ) _{2 ,} ZrO( _SO4 ), HF( _OOCCH3 ) ₄ , HF( _CO3 ) ₂ , HF _{( NO3} ) ₄ , HF( _SO4 ) ₂ , _HFOCl2 , _HFF4 , _HFCl4 , V( _CH3COCHCOCH3 ) ₃ , VOSO4, _VOCl3 , _{VCl3 , VCl4} , VBr ₃ , and the like.

Also, Cr( _{CH3COCHCOCH3 ) 3} , Cr( _OOCCH3 ) _2OH , Cr( _NO3 ) ₃ , Cr( _ClO4 ) ₃ , _CrPO4 , _Cr2 ( _SO4 ) ₃ , _{CrO2Cl2 ,} CrF ₃ , _CrCl3 , _CrBr3 , _CrI3 , Mn( _OOCCH3 ) ₂ , Mn( _CH3COCHCOCH3 ) ₂ , _MnCO3 , Mn( _NO3 ) ₂ , MnO, _Mn ( _ClO4 ) ₂ , _MnF2 , MnCl ₂ , Fe( _OOCCH3 ) ₂ , Fe( _{CH3COCHCOCH3 ) 3} , _FeCO3 , Fe( _NO3 ) ₃ , Fe( _ClO4 ) ₃ , FePO4 _{, FeSO4} , _Fe2 ( _SO4 ) ₃ , FeF3 , FeCl ₃ , FeC ₆ H ₅ O ₇ and the like.

In addition, Co( _OOCCH3 ) ₂ , Co( _{CH3COCHCOCH3 ) 3} , _CoCO3 , _Co ( _NO3 ) ₂ , _CoC2O4 , Co( _ClO4 ) ₂ , _Co3 ( _PO4 ) ₂ , _CoSO4 , CoF ₂ , CoCl ₂ , NiCO ₃ , Ni(NO ₃ ) ₂ , NiC ₂ O ₄ , Ni(ClO ₄ ) ₂ , NiSO ₄ , NiCl ₂ , NiBr ₂ and the like.
Furthermore, Zn( _OOCCH3 ) ₂ , Zn( _{CH3COCHCOCH3 ) 2} , _ZnCO3 , Zn( _NO3 ) ₂ , Zn( _ClO4 ) ₂ , _Zn3 ( _PO4 ) ₂ , _ZnSO4 , ZnF2 _, ZnCl ₂ , _AlF3 , _AlCl3 , AlBr3, _AlI3 , _{Al2 ( SO4} ) _{3 , Al2} ( _C2O4 ) ₃ , Al _{( CH3COCHCOCH3} ) ₃ , Al( _NO3 ) ₃ , _AlPO4 , GeCl ₄ , GeBr ₄ , GeI ₄ and the like.

<Alkaline treatment>:
In addition to the acid or salt treatment, the following alkali treatment or organic substance treatment may be performed as necessary. LiOH, NaOH, KOH, Mg(OH) ₂ , Ca(OH) ₂ , Sr(OH) ₂ , Ba(OH) ₂ and the like are exemplified as treatment agents used in alkali treatment.

<Organic matter treatment>:
Examples of organic processing agents used for organic matter processing include trimethylammonium, triethylammonium, N,N-dimethylanilinium, triphenylphosphonium, and the like.
Examples of the anions constituting the organic treatment agent include hexafluorophosphate, tetrafluoroborate, tetraphenylborate, etc., in addition to the anions exemplified as the anions constituting the salt treatment agent. It is not limited to these.

Moreover, these processing agents may be used alone, or two or more of them may be used in combination. These combinations may be used in combination for processing agents added at the start of processing, or may be used in combination for processing agents added during processing. Chemical treatments can also be performed multiple times with the same or different treatment agents.
These ion-exchange layered silicates usually contain adsorbed water and interlayer water. In the present invention, it is preferable to remove these adsorbed water and interlayer water and use them as the catalyst component (B).

The method of heat-treating the adsorbed water of the ion-exchange layered silicate and the interlayer water is not particularly limited, but it is necessary to select conditions so that the interlayer water does not remain and structural destruction does not occur. The heating time is 0.5 hours or longer, preferably 1 hour or longer. At that time, the moisture content of the catalyst component (B) after removal was 3% by weight when the moisture content when dehydrated for 2 hours at a temperature of 200° C. and a pressure of 1 mmHg (133 Pa) was assumed to be 0% by weight. % or less, preferably 1 wt % or less.

As described above, in the present invention, particularly preferred as the catalyst component (B) is an ion-exchange layered silicic acid having a water content of 3% by weight or less obtained by salt treatment and/or acid treatment. is salt.

The ion-exchange layered silicate is preferable because it can be treated with the catalyst component (C) of the organoaluminum compound described below before forming a catalyst or using it as a catalyst. The amount of the catalyst component (C) used per 1 g of the ion-exchangeable layered silicate is not limited, but is usually 20 mmol or less, preferably 0.5 mmol or more and 10 mmol or less. The treatment temperature and time are not limited, and the treatment temperature is usually 0° C. or higher and 70° C. or lower, and the treatment time is 10 minutes or longer and 3 hours or shorter. Washing after treatment is also possible and preferred. As the solvent, the same hydrocarbon solvent as used in the prepolymerization method or slurry polymerization method, which will be described later, is used.

Moreover, it is preferable to use spherical particles having an average particle size of 5 μm or more as the catalyst component (B). As long as the particles have a spherical shape, natural products or commercially available products may be used as they are, or particles whose shape and particle size have been controlled by granulation, sizing, fractionation, or the like may be used.
Examples of the granulation method used here include a stirring granulation method and a spray granulation method, and commercially available products can also be used.
In addition, organic substances, inorganic solvents, inorganic salts, and various binders may be used during granulation.
The spherical particles obtained as described above desirably have a compressive breaking strength of 0.2 MPa or more, particularly preferably 0.5 MPa or more, in order to suppress crushing and generation of fine powder in the polymerization process. In the case of such particle strength, the effect of improving particle properties is effectively exhibited particularly when prepolymerization is carried out.

(3) catalyst component (C)
Catalyst component (C) is an organoaluminum compound. A compound represented by the general formula: (AlR ³¹ _q Z _3-q ) _p is suitable as the organoaluminum compound used as the catalyst component (C).
Needless to say, in the present invention, the compounds represented by this formula can be used singly, in combination or in combination. In this formula, R ³¹ represents a hydrocarbon group having 1 to 20 carbon atoms, and Z represents halogen, hydrogen, alkoxy group or amino group. q represents an integer of 1-3 and p represents an integer of 1-2. R ³¹ is preferably an alkyl group, and Z is chlorine when it is a halogen group, an alkoxy group with 1 to 8 carbon atoms when it is an alkoxy group, and 1 to 8 carbon atoms when it is an amino group. Eight amino groups are preferred.

Specific examples of organoaluminum compounds include trimethylaluminum, triethylaluminum, tri-normal-propylaluminum, tri-normal-butylaluminum, triisobutylaluminum, tri-normal-hexylaluminum, tri-normal-octylaluminum, tri-normal-decyl-aluminum, diethylaluminum chloride, and diethylaluminum. sesquichloride, diethylaluminum hydride, diethylaluminum ethoxide, diethylaluminum dimethylamide, diisobutylaluminum hydride, diisobutylaluminum chloride and the like.
Among these, preferred are trialkylaluminums with p=1 and q=3 and dialkylaluminum hydrides with p=1 and q=2. More preferably, R ³¹ is a trialkylaluminum having 1 to 8 carbon atoms.

(4) Formation of Catalyst and Preliminary Polymerization The catalyst is formed by contacting each of the above catalyst components (A) to (C) in a (preliminary) polymerization tank simultaneously or continuously or once or multiple times. can be formed by
Contacting of the components is generally carried out in an aliphatic or aromatic hydrocarbon solvent. The contact temperature is not particularly limited, but it is preferably between -20°C and 150°C. As the order of contact, any suitable combination is possible, but particularly preferred ones for each component are as follows.
When using the catalyst component (C), before contacting the catalyst component (A) and the catalyst component (B), the catalyst component (A), or the catalyst component (B), or the catalyst component (A) and the catalyst contacting both component (B) with catalyst component (C), or contacting catalyst component (A) with catalyst component (B) and contacting catalyst component (C) at the same time, or Although it is possible to contact catalyst component (C) after (A) and catalyst component (B) are contacted, preferably catalyst component (A) is contacted with catalyst component (B) before contacting catalyst component (B). It is a method of contacting either component (C).
Moreover, after contacting each component, it is possible to wash with an aliphatic hydrocarbon or aromatic hydrocarbon solvent.

The amounts of the catalyst components (A), (B) and (C) used are arbitrary. For example, the amount of catalyst component (A) used relative to catalyst component (B) is preferably in the range of 0.1 μmol to 1,000 μmol, particularly preferably 0.5 μmol to 500 μmol, per 1 g of catalyst component (B). The amount of the catalyst component (C) to the catalyst component (A) is preferably in the range of 0.01 to 5×10 ⁶ , particularly preferably 0.1 to 1×10 ⁴ in molar ratio of the transition metal. preferable.

The ratio of the component [A-1] (the compound represented by the general formula (a1)) and the component [A-2] (the compound represented by the general formula (a2)) used in the present invention is a propylene-based The molar ratio of the transition metal of [A-1] to the total amount of each component [A-1] and [A-2] is preferably 0.30 or more, although it is arbitrary within the range that satisfies the above characteristics of the polymer. , is less than or equal to 0.99.
By changing this ratio, it is possible to adjust the balance between melt physical properties and catalytic activity. That is, the component [A-1] produces a low-molecular-weight terminal vinyl macromer, and the component [A-2] produces a high-molecular-weight polymer obtained by partially copolymerizing the macromer. Therefore, by changing the proportion of component [A-1], the average molecular weight, molecular weight distribution, deviation of the molecular weight distribution to the high molecular weight side, very high molecular weight components, branching (amount, length, distribution) can be controlled, thereby controlling melt physical properties such as degree of strain hardening, melt tension, and melt drawability.

In order to produce a propylene polymer with higher strain hardening, it is preferably 0.30 or more, more preferably 0.40 or more, and still more preferably 0.5 or more. The upper limit is preferably 0.99 or less, more preferably 0.95 or less, still more preferably 0.90 or less in order to efficiently obtain polypropylene resin (X) with high catalytic activity. Range.
Also, by using the component [A-1] within the above range, it is possible to adjust the balance between the average molecular weight and the catalytic activity with respect to the amount of hydrogen.

The catalyst according to the present invention is subjected to a prepolymerization treatment comprising contacting an olefin with it to polymerize a small amount. By carrying out the preliminary polymerization treatment, it is possible to prevent the formation of gel when the main polymerization is carried out. The reason for this is thought to be that the long chain branches can be uniformly distributed among the polymer particles when the main polymerization is carried out, and the melt physical properties can be improved thereby.

The olefin used for prepolymerization is not particularly limited, but propylene, ethylene, 1-butene, 1-hexene, 1-octene, 4-methyl-1-pentene, 3-methyl-1-butene, vinylcycloalkane, Styrene and the like can be exemplified. The method of feeding the olefin may be any method such as a method of feeding the olefin to the reactor at a constant rate or maintaining a constant pressure, a combination thereof, or a stepwise change.
The prepolymerization temperature and time are not particularly limited, but are preferably in the range of -20°C to 100°C and 5 minutes to 24 hours. The weight ratio of the prepolymerized polymer to the catalyst component (B) is preferably 0.01 to 100, more preferably 0.1 to 50. Moreover, the catalyst component (C) can be added or added during the preliminary polymerization. It is also possible to wash after the completion of preliminary polymerization.

It is also possible to coexist a polymer such as polyethylene or polypropylene, or an inorganic oxide solid such as silica or titania during or after contacting the above components.

(5) Use of Catalyst/Polypropylene Polymerization The polymerization mode is any mode as long as the olefin polymerization catalyst containing the catalyst component (A), the catalyst component (B) and the catalyst component (C) and the monomer are efficiently brought into contact with each other. can be adopted.
Specifically, a slurry polymerization method using an inert solvent, a so-called bulk polymerization method using propylene as a solvent without substantially using an inert solvent, a solution polymerization method, or a gas polymerization method using each monomer substantially without using a liquid solvent. A gas-phase polymerization method that maintains the shape can be employed. Further, a method of conducting continuous polymerization or batchwise polymerization is also applied. In addition to single-stage polymerization, multi-stage polymerization of two or more stages is also possible.
In the case of the slurry polymerization method, a saturated aliphatic or aromatic hydrocarbon such as hexane, heptane, pentane, cyclohexane, benzene, toluene or the like is used singly or as a mixture as a polymerization solvent.

Moreover, the polymerization temperature is 0° C. or higher and 150° C. or lower. In particular, when a bulk polymerization method is used, the temperature is preferably 40°C or higher, more preferably 50°C or higher. The upper limit is preferably 80°C or lower, more preferably 75°C or lower.
Furthermore, when a gas phase polymerization method is used, the temperature is preferably 40° C. or higher, more preferably 50° C. or higher. The upper limit is preferably 100°C or lower, more preferably 90°C or lower.
The polymerization pressure is preferably 1.0 MPa or more and 5.0 MPa or less. In particular, when bulk polymerization is used, the pressure is preferably 1.5 MPa or more, more preferably 2.0 MPa or more. Moreover, the upper limit is preferably 4.0 MPa or less, more preferably 3.5 MPa or less.

Furthermore, when a gas phase polymerization method is used, the pressure is preferably 1.5 MPa or more, more preferably 1.7 MPa or more. Further, the upper limit is preferably 2.5 MPa or less, more preferably 2.3 MPa or less.
Furthermore, hydrogen can be used as a molecular weight modifier and for the effect of improving activity in a molar ratio of 1.0×10 ⁻⁶ or more and 1.0×10 ⁻² or less with respect to propylene. can.

In addition, by changing the amount of hydrogen used, in addition to the average molecular weight of the polymer to be produced, the molecular weight distribution, the bias of the molecular weight distribution to the high molecular weight side, very high molecular weight components, branching (amount, length, distribution) can be controlled, thereby controlling the melt physical properties that characterize polypropylene having a long chain branched structure, such as MFR, strain hardening, melt tension MT, and melt drawability.
Therefore, the molar ratio of hydrogen to propylene is preferably 1.0×10 ⁻⁶ or more, preferably 1.0×10 ⁻⁵ or more, and more preferably 1.0×10 ⁻⁴ or more. is good. As for the upper limit, it is preferably 1.0×10 ⁻² or less, preferably 0.9×10 ⁻² or less, and more preferably 0.8×10 ⁻² or less.

In addition to the propylene monomer, copolymerization may also be carried out using α-olefin comonomers having 2 to 20 carbon atoms other than propylene, such as ethylene and/or 1-butene, as comonomers, depending on the application.
Therefore, in order to obtain a polypropylene resin (X) used in the present invention with a good balance between catalytic activity and melt properties, ethylene and/or 1-butene should be used in an amount of 15 mol% or less with respect to propylene. is preferred, more preferably 10.0 mol % or less, and still more preferably 7.0 mol % or less.

When propylene is polymerized using the catalyst and polymerization method exemplified here, a special chain transfer reaction generally called β-methyl elimination occurs from the active species derived from the catalyst component [A-1], and one end of the polymer is mainly propenyl structure, so-called macromers are formed. It is believed that this macromer can produce a higher molecular weight and is incorporated into the active species derived from the catalyst component [A-2], which has better copolymerizability, and the macromer copolymerization proceeds. Therefore, it is considered that the branched structure of the resulting polypropylene resin having a long-chain branched structure is mainly a comb-shaped chain.

8. Other properties of the polypropylene resin (X) having a long-chain branched structure As a further additional feature of the polypropylene resin (X) having a long-chain branched structure used in the present invention, which is produced by the above method, the strain rate is 0. The strain hardening degree (λmax(0.1)) in measurement of elongational viscosity at .1 s ⁻¹ is preferably 6.0 or more.
The degree of strain hardening (λmax(0.1)) is an index representing the strength at the time of melting, and when this value is large, there is an effect of improving the melt tension. As a result, the closed cell ratio can be increased when foam molding is performed. When the degree of strain hardening is preferably 6.0 or more, the closed-cell property can be maintained at a higher level, and it is more preferably 8.0 or more.

The details of the method for calculating λmax(0.1) are described below.
・ λmax (0.1) calculation method Elongational viscosity at a temperature of 180 ° C and strain rate = 0.1s ^-1 , time t (seconds) on the horizontal axis, and elongational viscosity η _E (Pa · seconds) on the vertical axis Plot on a log-log graph. On the log-log graph, the viscosity immediately before strain hardening is approximated by a straight line.
Specifically, first, the slope at each time when the extensional viscosity is plotted against time is obtained. take advantage of For example, there is a method in which the slopes of adjacent data are obtained and a moving average of several surrounding points is taken.
The extensional viscosity becomes a simple increasing function in the region of low strain amount, gradually approaches a constant value, and agrees with the Truton viscosity after a sufficient period of time if there is no strain hardening. When the strain amount (=strain rate x time) is about 1, the extensional viscosity begins to increase with time. That is, the above slope tends to decrease with time in the low strain region, but tends to increase from a strain amount of about 1, and an inflection point exists on the curve when the extensional viscosity is plotted against time. . Therefore, the strain amount is in the range of about 0.1 to 2.5, and the point where the slope at each time obtained above takes the minimum value is obtained, a tangent line is drawn at that point, and a straight line is drawn when the strain amount is 4.0. Extrapolate until . The maximum value (ηmax) of the elongational viscosity _ηE until the amount of strain reaches 4.0 is obtained, and the viscosity on the approximate straight line up to that time is defined as ηlin. ηmax/ηlin is defined as λmax(0.1).

The polypropylene resin (X) having a long-chain branched structure used in the present invention preferably has high stereoregularity as described above, which enables the production of molded articles with high rigidity. The polypropylene resin (X) is homopolypropylene, or propylene-α with a small amount of ethylene, α-olefins such as 1-butene and 1-hexene, and other comonomers, as long as it satisfies the various properties described above. - It may be an olefin random copolymer. When the polypropylene resin (X) is homopolypropylene, the crystallinity is high and the melting peak temperature is high. High temperatures are preferred.
More specifically, the melting peak temperature obtained by differential scanning calorimetry (DSC) is preferably 145°C or higher, more preferably 150°C or higher. A melting peak temperature higher than 145°C is preferable from the viewpoint of heat resistance of the product, but the upper limit of the melting peak temperature of the polypropylene resin (X) is usually 170°C or lower.
The melting peak temperature is determined by differential scanning calorimetry (DSC). After removing the heat history by once raising the temperature to 200° C., the temperature is lowered to 40° C. at a rate of 10° C./min, and then again. It is defined as the endothermic peak top temperature measured at a heating rate of 10°C/min.

II. Propylene block copolymer (Y)
As the propylene-based block copolymer (Y), which is a component constituting the polypropylene-based resin composition according to the present invention, a propylene (co)polymer (Y-1) (hereinafter referred to as Propylene-based block copolymer (Y), which is a multistage polymer consisting of (also referred to as "(Y-1)") and a propylene-ethylene copolymer (Y-2) (hereinafter also referred to as "(Y-2)") Use
The term block copolymer used herein is a common name for a propylene-based resin composition obtained by performing multistage polymerization by a sequential polymerization method, which is commonly used by those skilled in the art. It differs from so-called (real) block copolymers or graft copolymers in which polymerized components are bonded together by chemical bonds. Since the components produced in each step of multi-step polymerization are not chemically bonded, in general, crystallinity fractionation is performed using differences in crystallinity, molecular weight, solubility in solvents, etc. for each component. It is possible to separate each component produced in each step by a method such as molecular weight fractionation, solubility fractionation, or the like.
In addition, in the block copolymer (Y) obtained by this conventionally known sequential polymerization method, the presence of a long-chain branched structure due to chemical bonds like the polypropylene resin (X) is not recognized with analytical precision.

The propylene-based block copolymer (Y) may be produced using any of conventionally known Ziegler-Natta catalysts, metallocene catalysts, and the like. Various combinations of polymerization methods, gas phase polymerization methods, etc. can be used.
Ziegler-Natta catalysts are described, for example, in "Polypropylene Handbook" Edward P. Moore Jr. Edited and edited by Tetsuo Yasuda and Nobu Sakuma, translated and supervised by Kogyo Research Institute (1998), Section 2.3.1 (pages 20 to 57). A titanium trichloride-based catalyst composed of an organoaluminum hydride, a solid catalyst component essentially containing magnesium chloride, a titanium halide, and an electron-donating compound, a magnesium-supported catalyst composed of an organoaluminum and an organosilicon compound, and a solid catalyst component. It refers to a catalyst in which an organoaluminum compound component is combined with an organosilicon-treated solid catalyst component formed by contacting an organoaluminum and an organosilicon compound. In addition, the metallocene catalyst has already been described in detail in the above description of "Method for producing polypropylene resin (X)". Among the above examples, those using the component [A-2] as the catalyst component (A) are preferably used for the production of the propylene-based block copolymer (Y).

Preferred catalysts include, for example, a titanium trichloride composition obtained by reducing titanium tetrachloride with an organoaluminum compound and further treating it with various electron donors and electron acceptors, an organoaluminum compound, and an aromatic carboxylic acid ester. (See JP-A-56-100806, JP-A-56-120712, and JP-A-58-104907), and magnesium halide with titanium tetrachloride and various electron donors. can be exemplified by supported catalysts (see JP-A-57-63310, JP-A-63-43915 and JP-A-63-83116).

The propylene (co)polymer (Y-1) produced in the first stage of the sequential polymerization is either a propylene homopolymer or a propylene random copolymer obtained by copolymerizing a small amount of comonomer within the scope of the present invention. is. As comonomers, α-olefins having up to about 10 carbon atoms excluding 3, such as ethylene, 1-butene and 1-hexene, are usually used. When a comonomer is contained, it can be exemplified that the comonomer content in the propylene (co)polymer (Y-1) is 0.1 to 5.0% by weight (however, the propylene (co)polymer (Y -1) is 100% by weight).

1. Characteristic (Yi): Quantity ratio of (Y-1) and (Y-2) In the present invention, the weight ratio of (Y-1) and (Y-2) is 50 to 99 for (Y-1). % by weight, preferably 55 to 97% by weight, more preferably 60 to 95% by weight. Correspondingly, (Y-2) is 1-50% by weight, preferably 3-45% by weight, more preferably 5-40% by weight.
(However, the total weight of the propylene-based block copolymer (Y) is 100% by weight)
When the amount of (Y-2) is 1% by weight or more, the melt tension does not become too low and is suitable for foam molding. is not too small, the heat resistance and rigidity of the composition are not impaired.

2. Characteristic (Y-ii): MFR
The MFR range of the propylene-based block copolymer (Y) used in the present invention is in the range of 0.1 to 200 g/10 minutes, preferably 0.2 to 190 g/10 minutes, more preferably 0.5. ~180 g/10 min, particularly preferably in the range from 2.1 to 170 g/10 min.
This is a commonly used range for the MFR of resins used for various moldings. On the other hand, when it is 200 g/10 minutes or less, problems such as increased neck-in during extrusion molding and difficulty in sheet take-up hardly occur.
The method for measuring MFR is the same as the method for measuring polypropylene resin (X) described above.

3. Property (Y-iii): Peak melting temperature The peak melting temperature of the propylene-based block copolymer (Y) used in the present invention must exceed 155°C from the viewpoint of maintaining the heat resistance of the sheet. and preferably 157° C. or higher. Although the upper limit of the melting peak temperature does not need to be particularly limited, it is practically difficult to produce a product with a melting peak temperature exceeding 170°C.
In addition, the melting peak temperature was measured by differential scanning calorimetry (DSC). It is defined as the endothermic peak top temperature when measured at a temperature rate of 10°C/min.

4. Characteristic (Y-iv): Ethylene content in propylene-ethylene copolymer (Y-2) In the present invention, the ethylene content in the propylene-ethylene copolymer (Y-2) is 11 to 60% by weight. is required (provided that the total weight of the monomers constituting the propylene-ethylene copolymer (Y-2) is 100% by weight). A preferred range of ethylene content in the propylene-ethylene copolymer (Y-2) is 11 to 38% by weight, more preferably 16 to 36% by weight, still more preferably 18 to 35% by weight.
When the ethylene content is within the above range, the dispersed state of (Y-2) in the polypropylene resin composition is improved, resulting in excellent foamability.

5. Property (Yv): Intrinsic viscosity of propylene-ethylene copolymer (Y-2) ), the intrinsic viscosity of the propylene-ethylene copolymer (Y-2), measured at 135°C using decalin as a solvent, must be 5.3 dl/g or more, preferably 6.0 dl/g. g or more, more preferably 7.0 dl/g or more, most preferably 7.5 dl/g or more.

When the intrinsic viscosity value is 5.3 dl/g or more, the melt tension is high and the foamability is good.
The upper limit does not have to be specified, but if it is too high, it may cause gelation, so it is 25.0 dl/g or less, preferably 20.0 dl/g or less, more preferably 18.0 dl/g or less. , and most preferably 16.0 dl/g or less.
Here, the intrinsic viscosity is a value measured using a Ubbelohde capillary viscometer at a temperature of 135° C., using decalin as a solvent. In order to determine the intrinsic viscosity of (Y-2), using the same method as described in CXS above, the (Y-2) component is recovered as a 25 ° C. paraxylene soluble component, and its intrinsic viscosity is measured. Assumed to be performed. However, when the ethylene content of the (Y-2) component is less than 15% by weight, it becomes difficult to sufficiently separate the (Y-2) component by the CXS technique. In such a case, during the sequential polymerization, a small amount of the (Y-1) component after the completion of the production of the propylene (co)polymer (Y-1) produced in the preceding stage of the sequential polymerization is extracted and The viscosity is measured, and the intrinsic viscosity of the entire (Y) after the completion of the sequential polymerization is measured and obtained by the following formula.
Intrinsic viscosity of component (Y-2) = [intrinsic viscosity of whole (Y) - {intrinsic viscosity of component (Y-1) x weight fraction of component (Y-1)/100}]/{(Y-2 ) component weight fraction/100}

Here, as a method for determining the ratio of (Y-1) and (Y-2) in component (Y) and the ethylene content in (Y-2), conventionally known IR, NMR, or solubility fractionation It can be determined by an analysis method or the like that combines the method and the IR method.
In the present invention, various indexes of mainly component (Y) were determined by a combination of the cross-fractionation method and the FT-IR method described below.

(1) Analyzer to be used (i) Cloth fractionator Dia Instruments CFC T-100 (abbreviated as CFC)
(ii) Fourier transform infrared absorption spectrum analysis FT-IR analyzer: PerkinElmer 1760X
The wavelength-fixed infrared spectrophotometer installed as a CFC detector is removed, and an FT-IR is connected instead, and this FT-IR is used as a detector. The transfer line between the outlet of the solution eluted from the CFC and the FT-IR has a length of 1 m and is kept at 140° C. throughout the measurement. The flow cell attached to the FT-IR has an optical path length of 1 mm and an optical path width of 5 mmφ, and is kept at 140° C. throughout the measurement.
(iii) gel permeation chromatography (GPC)
Three AD806MS manufactured by Showa Denko K.K. are connected in series and used as the GPC column in the latter stage of the CFC.

(2) CFC measurement conditions (i) Solvent: ortho-dichlorobenzene (ODCB)
(ii) sample concentration: 4 mg/mL
(iii) injection volume: 0.4 mL
(iv) Crystallization: The temperature is lowered from 140°C to 40°C over about 40 minutes.
(v) Separation method:
The fractionation temperatures during temperature-rising elution fractionation are 40, 100, and 140°C, and fractionation is performed into three fractions in all. The elution ratio (unit: weight %) of the component that elutes at 40°C or lower (fraction 1), the component that elutes at 40-100°C (fraction 2), and the component that elutes at 100-140°C (fraction 3) is shown. They are defined as W40, W100 and W140. W40+W100+W140=100. Each separated fraction is automatically transported directly to the FT-IR analyzer.
(vi) Solvent flow rate during elution: 1 mL/min

(3) FT-IR measurement conditions After the sample solution starts to be eluted from GPC in the latter stage of CFC, FT-IR measurement is performed under the following conditions, and GPC-IR data is collected for each of the fractions 1 to 3 described above. .
Conceptual diagrams of CFC-FT-IR are shown in, for example, JP-A-2018-135419 and JP-A-2017-031359.
(i) Detector: MCT
(ii) Resolution: 8 cm ⁻¹
(iii) Measurement interval: 0.2 minutes (12 seconds)
(iv) Accumulation times per measurement: 15 times

(4) Post-processing and Analysis of Measurement Results The eluted amount and molecular weight distribution of the components eluted at each temperature are determined using the absorbance at 2945 cm ⁻¹ obtained by FT-IR measurement as a chromatogram. The eluted amount is normalized so that the total eluted amount of each eluted component is 100%. Conversion from the retention volume to the molecular weight is performed using a previously prepared standard polystyrene calibration curve. The specific method is the same as described above.
The ethylene content distribution (distribution of ethylene content along the molecular weight axis) of each elution component is obtained by using the ratio of the absorbance at 2956 cm ⁻¹ and the absorbance at 2927 cm ⁻¹ obtained by GPC-IR, and the ratio of ¹³ Convert to ethylene content (% by weight) using a calibration curve prepared in advance using ethylene-propylene rubber (EPR) and mixtures thereof whose ethylene content is known by C-NMR measurement etc. and ask.

(5) Propylene-ethylene copolymer content The propylene-ethylene copolymer (Y-2) (hereinafter referred to as EP) content of the propylene-based block copolymer (Y) in the present invention is determined by the following formula (I ) and is obtained by the following procedure.
EP content (% by weight) = W40 x A40/B40 + W100 x A100/B100 + W140 x A140/B140 (I)
W40, W100, W140 are the elution ratios (unit: weight %) in each fraction described above, and A40, A100, A140 are the average ethylene contents of actual measurements in each fraction corresponding to W40, W100, W140. (unit: % by weight), and B40, B100 and B140 are the ethylene contents (unit: % by weight) of EP contained in each fraction.
How to obtain A40, A100, A140, B40, B100, and B140 will be described later.
The meaning of the formula (I) is as follows. The first term on the right side of formula (I) is a term for calculating the amount of EP contained in Fraction 1 (a portion soluble at 40°C). When Fraction 1 contains only EP and does not contain PP, W40 directly contributes to the EP content derived from Fraction 1, but Fraction 1 contains a small amount of EP-derived components. Since PP-derived components (extremely low molecular weight components and atactic polypropylene) are also included, it is necessary to correct that part. Therefore, by multiplying W40 by A40/B40, the amount derived from the EP component in Fraction 1 is calculated. For example, if the average ethylene content (A40) of fraction 1 is 30% by weight and the ethylene content (B40) of EP contained in fraction 1 is 40% by weight, 30/40 of fraction 1 = 3/4 (that is, 75% by weight) is derived from EP and the remaining 1/4 is derived from PP. Thus, the operation of multiplying A40/B40 in the first term on the right side means calculating the contribution of EP from the weight % of fraction 1 (W40). The same is true for the second term on the right side and thereafter, and the EP content is obtained by calculating the contribution of EP for each fraction and adding them together.

(i) As described above, A40, A100, and A140 are the average ethylene contents corresponding to fractions 1 to 3 obtained by CFC measurement (all units are % by weight). How to obtain the average ethylene content will be described later.
(ii) B40 is the ethylene content corresponding to the peak position in the differential molecular weight distribution curve of fraction 1 (the unit is % by weight). Fractions 2 and 3 are considered to be completely eluted from the rubber portion at 40° C. and cannot be defined by the same definition. B40, B100 and B140 are the ethylene contents of EP contained in each fraction, but it is practically impossible to analytically determine these values. The reason is that there is no means for completely separating and fractionating PP and EP mixed in the fraction. As a result of examination using various model samples, it was found that B40 can well explain the effect of improving material properties by using the ethylene content corresponding to the peak position of the differential molecular weight distribution curve of Fraction 1. Ta. In addition, B100 and B140 have ethylene chain-derived crystallinity, and the amount of EP contained in these fractions is relatively small compared to the amount of EP contained in fraction 1. There are two reasons for this. Therefore, approximating both to 100 is closer to the actual situation and causes almost no error in calculation. Therefore, the analysis is performed with B100=B140=100.

(iii) Determine the EP content according to the following formula.
EP content (% by weight) = W40 x A40/B40 + W100 x A100/100 + W140 x A140/100 (II)
That is, W40×A40/B40, which is the first term on the right side of formula (II), indicates the EP content (% by weight) having no crystallinity, and W100×A100/, which is the sum of the second and third terms. 100+W140×A140/100 indicates the EP content (% by weight) having crystallinity.
Here, average ethylene contents A40, A100 and A140 of fractions 1 to 3 obtained by B40 and CFC measurement are obtained as follows.
A curve obtained by measuring the molecular weight distribution of fraction 1 fractionated by the difference in crystal distribution with a GPC column that constitutes a part of the CFC analyzer, and an FT-IR connected behind the GPC column. A corresponding measured ethylene content distribution curve is determined. The ethylene content corresponding to the peak position of the differential molecular weight distribution curve is B40.
Also, the sum of the products of the weight ratio for each data point and the ethylene content for each data point, which are taken in as data points during measurement, is the average ethylene content A40.

The significance of setting the three types of separation temperatures is as follows.
In the CFC analysis of the present invention, 40 ° C. is only for polymers without crystallinity (for example, most of EP, or extremely low molecular weight components and atactic components among propylene polymer components (PP)). It has the significance of being a necessary and sufficient temperature condition for separation. In addition, 100 ° C. is a component that is insoluble at 40 ° C. but becomes soluble at 100 ° C. (for example, components having crystallinity due to ethylene and / or propylene chains in EP, and PP) is a necessary and sufficient temperature to elute only. Furthermore, 140 ° C. means components that are insoluble at 100 ° C. but soluble at 140 ° C. (e.g., components with particularly high crystallinity in PP and components with extremely high molecular weight and ethylene crystallinity in EP ) and recovering the entire amount of the propylene-based block copolymer used for analysis. The amount of EP component contained in W140 is extremely small and can be practically ignored.
Ethylene content in EP (% by weight) = (W40 x A40 + W100 x A100 + W140 x A140) / [EP] (III)
However, [EP] is the EP content (% by weight) determined previously.
The ethylene content (E) (% by weight) of the portion having no crystallinity in the EP is approximated by the value of B40, since the elution of the rubber portion is almost completed at 40° C. or less.

However, in the above-described analysis method using a combination of the cross fractionation method and the FT-IR method, the ethylene content of (Y-2) is less than 15% by weight, and there is no significant difference in crystallinity from (Y-1). Accurate analysis becomes difficult in cases where the separation by the method cannot be performed sufficiently. In such a case, the component (Y-1) after completion of the production of the propylene (co)polymer (Y-1) produced in the preceding stage of the sequential polymerization is extracted during the sequential polymerization, and its molecular weight is (When comonomers are copolymerized, the comonomer content is also measured) is measured, and the quantitative ratio of the (Y-1) component and the (Y-2) component is determined by calculation using material balance, and further, By measuring the comonomer content of component (Y) as a whole at the end of the sequential polymerization, it is preferable to determine the comonomer content of component (Y-2) using the simple addition rule of weights below. If ethylene is used as a comonomer, the ethylene content of (Y-2) shall be determined by the following formula.
Ethylene content of component (Y-2) = [entire ethylene content of (Y) - {ethylene content of component (Y-1) x weight fraction of component (Y-1)/100}]/{(Y-2) ) component weight fraction/100}

As for other methods for determining the quantitative ratio of the component (Y-1) and the component (Y-2), when the average molecular weights of the component (Y-1) and the component (Y-2) are different to some extent, , Perform GPC measurement of the entire (Y) after the completion of the sequential polymerization, separate the peaks of the resulting multimodal molecular weight distribution curve using commercially available data analysis software, etc., and calculate the weight ratio. can also

6. Characteristics: Blending amount of propylene-based block copolymer (Y) More preferably 15.0 to 55.0 parts by weight, still more preferably 17.5 to 52.5 parts by weight (provided that the total of (X), (Y) and (Z) is 100 parts by weight) . When the blending amount of the propylene-based block copolymer (Y) is within this range, shear heat generation and take-up are not observed even when molding is performed at high speed by the T-die method and at a high expansion ratio exceeding 3.0 times. The load applied to the sheet can be reduced by the tension, and a foamed sheet having excellent cell isolation and denseness as well as excellent appearance can be obtained. Also, when the blending amount is 67.5 parts by weight or less, the fluidity is sufficient, and there is no problem that the load on the extruder is too high for various moldings. , the melt tension becomes sufficient, the properties as a high melt tension material are excellent, and the material is suitable for foam molding.

III. Propylene-α-olefin random copolymer (Z)
The propylene-α-olefin random copolymer (Z) is produced using a conventionally known Ziegler-Natta catalyst, and can be produced by a conventionally known slurry polymerization method, bulk polymerization method, gas phase polymerization method, or the like. Various combinations can be used.
Here, Ziegler-Natta catalysts are described, for example, in "Polypropylene Handbook" Edward P. Moore Jr. Edited and edited by Tetsuo Yasuda and Nobu Sakuma, translated and supervised by Kogyo Research Institute (1998), Section 2.3.1 (pages 20 to 57). A titanium trichloride-based catalyst composed of an organoaluminum hydride, a solid catalyst component essentially containing magnesium chloride, a titanium halide, and an electron-donating compound, a magnesium-supported catalyst composed of an organoaluminum and an organosilicon compound, and a solid catalyst component. It refers to a catalyst in which an organoaluminum compound component is combined with an organosilicon-treated solid catalyst component formed by contacting an organoaluminum and an organosilicon compound.
Preferred catalysts include, for example, a titanium trichloride composition obtained by reducing titanium tetrachloride with an organoaluminum compound and further treating it with various electron donors and electron acceptors, an organoaluminum compound, and an aromatic carboxylic acid ester. (See JP-A-56-100806, JP-A-56-120712, and JP-A-58-104907), and magnesium halide with titanium tetrachloride and various electron donors. can be exemplified by supported catalysts (see JP-A-57-63310, JP-A-63-43915 and JP-A-63-83116).

As the α-olefin of the propylene-α-olefin random copolymer (Z), α-olefins having up to about 10 carbon atoms excluding 3, such as ethylene, 1-butene and 1-hexene, can be selected.

As a result of many experiments and studies, the present inventors found that when the propylene-α-olefin random copolymer (Z) blended in the polypropylene resin composition has the following characteristics, it is molded at a particularly high speed. In die foam molding, even in a foam sheet with a high expansion ratio of more than 3.0 times, a polypropylene-based foam having uniformly fine and highly independent foam cells and a good appearance of the molded product can be obtained. I found out. It is described in detail below.

1. Characteristic (Zi): Polymerized with a Ziegler-Natta catalyst The propylene-α-olefin random copolymer (Z) used in the present invention must be polymerized with a Ziegler-Natta catalyst. Propylene-α-olefin random copolymers polymerized with Ziegler-Natta catalysts are superior in plant productivity compared to those polymerized with metallocene catalysts. It is characterized by excellent fluidity under the surface and excellent productivity of the foam sheet.

2. Characteristic (Z-ii): The melting peak temperature measured by DSC is 157° C. or less. The melting peak temperature of the propylene-α-olefin random copolymer (Z) used in the present invention is In order to improve the extensibility of the resin, the temperature should be 157° C. or lower, preferably 156° C. or lower, more preferably 155° C. or lower, particularly preferably 154° C. or lower, and most preferably 153° C. or lower. is. In addition, the melting peak temperature was measured by differential scanning calorimetry (DSC). It is defined as the endothermic peak top temperature when measured at a temperature rate of 10°C/min.
When the melting peak temperature is 157° C. or less, the effect of maintaining independence of bubbles is exhibited. Although the lower limit of the melting peak temperature is not particularly defined, it is preferably 100° C. from the viewpoint of heat deformation resistance as a molded article.

3. Characteristic (Z-iii): Melt flow rate The melt flow rate (MFR) of the propylene-α-olefin random copolymer (Z) must be 21.0 g/10 minutes or more, preferably 21.0 to 100.0 g/10 min, more preferably 22.0 to 80.0 g/10 min, still more preferably 23.0 to 70.0 g/10 min, still more preferably 24.0 to 60.0 g /10 min, particularly preferably 25.0 to 55.0 g/10 min, most preferably 26.0 to 50.0 g/10 min. When the MFR of the propylene-α-olefin random copolymer (Z) is within this range, a polypropylene-based foam having uniform and fine foam cells, improved spreadability, and good appearance of molded articles can be obtained. . In addition, when the melt flow rate is 21.0 g/10 minutes or more, orientation-induced crystallization is less likely to occur when molding is performed, and in particular, when extruded sheets are molded in the T-die molding method, the cell walls are not destroyed, and the appearance is improved. It becomes a molded product excellent in When the melt flow rate is 100.0 g/10 minutes or less, the melt tension becomes high, which is suitable for foaming.
The method for measuring MFR is the same as the method for measuring polypropylene resin (X) described above.

4. Property: Blending amount of propylene-α-olefin random copolymer (Z) More preferably 30 to 70 parts by weight, still more preferably 35 to 65 parts by weight, particularly preferably 40 to 60 parts by weight (provided that the total of (X), (Y) and (Z) is 100 parts by weight ).
When the blending amount of the propylene-α-olefin random copolymer (Z) is within this range, it can be molded at high speed, especially by the T-die method, and even at a high expansion ratio exceeding 3.0 times, shear It is possible to reduce the load applied to the sheet due to heat generation and take-up tension, and to obtain a foamed sheet that is excellent in cell isolation and denseness and has excellent appearance. Further, when the blending amount is 10 parts by weight or more, the extensibility of the polypropylene resin composition is sufficient and the foamability is excellent, and when it is 75 parts by weight or less, the rigidity and melting peak temperature as the polypropylene resin composition is improved, and there is no deformation or melting as a molded product when used at high temperatures.

5. Property: α-olefin content As the α-olefin of the propylene-α-olefin random copolymer (Z), α-olefins with up to about 10 carbon atoms excluding 3, such as ethylene, 1-butene, and 1-hexene, can be used. It can be selected, but is preferably ethylene.
The α-olefin content in the propylene-α-olefin random copolymer (Z) is preferably 0.5 to 5.0% by weight, more preferably 0.8 to 4.5% by weight, and further It is preferably 0.9 to 4.0% by weight. When the α-olefin content is within this range, a polypropylene-based foam having uniform and fine foam cells, improved extensibility, and good appearance of molded articles can be obtained. Further, when the amount of α-olefin is 0.5% by weight or more, the spreadability of the propylene-α-olefin random copolymer (Z) is excellent, and when the amount of α-olefin is 5.0% by weight or less. , The propylene-α-olefin random copolymer (Z) has improved rigidity and melting peak temperature, and does not cause deformation or melting as a molded product when used at high temperatures.

IV. Crystallization nucleating agent (K)
The propylene-based resin composition of the present invention must contain a crystallization nucleating agent (K).
1. Characteristics: Types of crystallization nucleating agents The crystallization nucleating agents include nucleating agents composed of triaminobenzene derivatives, organic phosphoric ester metal salts, organic monocarboxylic acid metal salts, organic dicarboxylic acid metal salts, polymer nucleating agents, and dibenzylidene. Sorbitol or derivatives thereof, metal salts of diterpenic acids and the like are used.
Examples of the triaminobenzene derivatives include 1,3,5-tris[2,2-dimethylpropionylamino]benzene, 1,3,5-tris[cyclohexylcarbonylamino]benzene, 1,3,5-tris[4- methylbenzoylamino]benzene, 1,3,5-tris[3,4-dimethylbenzoylamino]benzene, 1,3,5-tris[3,5-dimethylbenzoylamino]benzene, 1,3,5-tris[ Cyclopentanecarbonylamino]benzene, 1,3,5-tris[1-adamantanecarbonylamino]benzene, 1,3,5-tris[2-methylpropionylamino]benzene, 1,3,5-tris[3,3 -dimethylbutyrylamino]benzene, 1,3,5-tris[2-ethylbutyrylamino]benzene, 1,3,5-tris[2,2-dimethylbutyrylamino]benzene, 1,3,5- tris[2-cyclohexyl-acetylamino]benzene, 1,3,5-tris[3-cyclohexyl-propionylamino]benzene, 1,3,5-tris[4-cyclohexyl-butyrylamino]benzene, 1,3,5- tris[5-cyclohexyl-valeroylamino]benzene, 1-isobutyrylamino-3,5-bis[pivaloylamino]benzene, 2,2-dimethylbutyrylamino-3,5-bis[pivaloylamino]benzene, 3, 3-dimethylbutyrylamino-3,5-bis[pivaloylamino]benzene, 1,3-bis[isobutyrylamino]-5-pivaloylaminobenzene, 1,3-bis[isobutyrylamino]-5 -(2,2-dimethyl-butyryl)aminobenzene, 1,3-bis[isobutyrylamino]-5-(3,3-dimethyl-butyryl)aminobenzene, 1,3-bis[2,2-dimethyl butyrylamino]-5-pivaloylaminobenzene, 1,3-bis[2,2-dimethylbutyrylamino]-5-isobutyrylaminobenzene, 1,3-bis[2,2-dimethylbutyryl amino]-5-(3,3-dimethylbutyryl)-aminobenzene, 1,3-bis[3,3-dimethylbutyrylamino]-5-pivaloylamino-benzene, 1,3-bis[3,3- dimethylbutyrylamino]-5-isobutyryl-aminobenzene, 1,3-bis[3,3-dimethylbutyrylamino]-5-(2,2-dimethyl-butyrylamino)aminobenzene or 1,3,5- Mention may be made of tris[3-(trimethylsilyl)propionylamino]benzene. Among these, 1,3,5-tris[2,2-dimethylpropionylamino]benzene is preferred.
Examples of the metal salts of organic phosphates include sodium-2,2′-methylene-bis(4,6-di-t-butylphenyl)phosphate, sodium-2,2′-ethylidene-bis(4,6 -di-t-butylphenyl)phosphate, lithium-2,2'-methylene-bis(4,6-di-t-butylphenyl)phosphate, lithium-2,2'-ethylidene-bis(4,6 -di-t-butylphenyl)phosphate, sodium-2,2'-ethylidene-bis(4-i-propyl-6-t-butylphenyl)phosphate, lithium-2,2'-methylene-bis(4 -methyl-6-t-butylphenyl)phosphate, lithium-2,2'-methylene-bis(4-ethyl-6-t-butylphenyl)phosphate, sodium-2,2'-butylidene-bis(4 ,6-di-methylphenyl) phosphate, sodium-2,2'-butylidene-bis(4,6-di-t-butylphenyl) phosphate, sodium-2,2'-t-octylmethylene-bis( 4,6-di-methylphenyl)phosphate, sodium-2,2'-t-octylmethylene-bis(4,6-di-t-butylphenyl)phosphate, calcium-bis[(2,2'- methylene-bis(4,6-di-t-butylphenyl)phosphate], magnesium-bis[2,2′-methylene-bis(4,6-di-t-butylphenyl)phosphate], zinc-bis [2,2′-methylene-bis(4,6-di-t-butylphenyl)phosphate], sodium-2,2′-methylene-bis(4-methyl-6-t-butylphenyl)phosphate, Sodium-2,2'-methylene-bis(4-ethyl-6-t-butylphenyl)phosphate, sodium-2,2'-ethylidene-bis(4-s-butyl-6-t-butylphenyl)phosphate phate, sodium-2,2'-methylene-bis(4,6-di-methylphenyl)phosphate, sodium-2,2'-methylene-bis(4,6-di-ethylphenyl)phosphate, potassium- 2,2′-ethylidene-bis(4,6-di-t-butylphenyl)phosphate, calcium-bis[2,2′-ethylidene-bis(4,6-di-t-butylphenyl)phosphate], magnesium-bis[2,2'-ethylidene-bis(4,6-di-t-butylphenyl)phosphate], zinc-bis[2,2'-ethylidene-bis(4,6-di-t-butyl phenyl)phosphate], aluminum-tris[2,2′-methylene-bis(4,6-di-t-butylphenyl)phosphate], aluminum-tris[2,2′-ethylidene-bis(4,6- di-t-butylphenyl)phosphate], aluminum hydroxy-bis[2,2′-methylene-bis(4,6-di-t-butylphenyl)phosphate], aluminum dihydroxy-2,2′- Methylene-bis(4,6-di-t-butylphenyl) phosphate and the like are exemplified.

Examples of the metal salts of organic monocarboxylic acids include metal salts such as benzoic acid and allyl-substituted acetic acid. metal salts such as pt-butylbenzoic acid, monophenylacetic acid, diphenylacetic acid, phenyldimethylacetic acid, adipic acid (for example, normal or basic salts of Li, Na, K, Mg, Ca, Zn or Al); etc. are exemplified. Examples of the organic dicarboxylic acid metal salts include metal salts of succinic acid, glutaric acid, adipic acid, suberic acid, sebacic acid, phthalic acid, cyclohexanecarboxylic acid, norbornane dicarboxylic acid (e.g., Li, Na, K, Mg , Ca, Zn or Al normal salt or basic salt). Examples of the polymer nucleating agent include polyvinylcyclohexane and poly-3-methyl-butene-1.

Examples of the dibenzylidene sorbitol or derivatives thereof include 1,3,2,4-dibenzylidene sorbitol, 1,3-benzylidene-2,4-p-methylbenzylidene sorbitol, 1,3-benzylidene-2,4- p-ethylbenzylidene sorbitol, 1,3-p-methylbenzylidene-2,4-benzylidene sorbitol, 1,3-p-ethylbenzylidene-2,4-benzylidene sorbitol, 1,3-p-methylbenzylidene-2,4 -p-ethylbenzylidene sorbitol, 1,3-p-ethylbenzylidene-2,4-p-methylbenzylidene sorbitol, 1,3,2,4-di(p-methylbenzylidene) sorbitol, 1,3,2,4 -di(p-ethylbenzylidene)sorbitol, 1,3,2,4-di(pn-propylbenzylidene)sorbitol, 1,3,2,4-di(pi-propylbenzylidene)sorbitol, 1, 3,2,4-di(pn-butylbenzylidene)sorbitol, 1,3,2,4-di(ps-butylbenzylidene)sorbitol, 1,3,2,4-di(pt- Butylbenzylidene)sorbitol, 1,3,2,4-di(p-methoxybenzylidene)sorbitol, 1,3,2,4-di(p-ethoxybenzylidene)sorbitol, 1,3-benzylidene-2,4-p - chlorobenzylidene sorbitol, 1,3-p-chlorobenzylidene-2,4-benzylidene sorbitol, 1,3-p-chlorobenzylidene-2,4-p-methylbenzylidene sorbitol, 1,3-p-chlorobenzylidene-2 ,4-p-ethylbenzylidene sorbitol, 1,3-p-methylbenzylidene-2,4-p-chlorobenzylidene sorbitol, 1,3-p-ethylbenzylidene-2,4-p-chlorobenzylidene sorbitol, 1,3 ,2,4-di(p-chlorobenzylidene)sorbitol, 1,2,3-trideoxy-4,6:5,7-bis-O-[(4-propylphenyl)methylene]-nonitol, etc. can be done. Particularly preferably, 1,3,2,4-dibenzylidenesorbitol, 1,3,2,4-di(p-methylbenzylidene)sorbitol, 1,3-p-chlorobenzylidene-2,4-p-methylbenzylidene Examples include sorbitol, 1,2,3-trideoxy-4,6:5,7-bis-O-[(4-propylphenyl)methylene]-nonitol and the like.

The metal salts of diterpenoic acids are reaction products of diterpenoic acids and predetermined metal compounds such as magnesium compounds and aluminum compounds. Diterpene acids are generally known as natural resins obtained from pine plants, specifically natural rosins such as gum rosin, tall oil rosin, wood rosin; disproportionated rosin, hydrogenated rosin, dehydrogenated Various modified rosins such as rosin, polymerized rosin, α,β-ethylenically unsaturated carboxylic acid-modified rosin; and purified products of the above-mentioned natural rosin and modified rosin are obtained as raw materials. Diterpenic acids include, for example, pimaric acid, sandaracopimaric acid, parastric acid, isopimaric acid, abietic acid, dehydroabietic acid, neoabietic acid, dihydropimaric acid, dihydroabietic acid, tetrahydroabietic acid and the like.

Among these, preferable crystallization nucleating agents are those represented by the following general formulas (1) to (3), which have a good balance between foamability and mechanical properties, and heat deformation resistance commensurate with foamability. It tends to be good and is preferable.

（式中、Ｒ^１は、直接結合、硫黄、炭素数１～９のアルキレン又は炭素数２～９のアルキリデンであり、Ｒ^２及びＲ^３は、同一又は異なって、それぞれ水素、炭素数１～８のアルキル又は炭素数７～９のアルキルアリールであり、ＭはＬｉ、Ｎａ、Ｋ、Ｍｇ、Ｃａ、Ｚｎ又はＡｌであり、ｎはＭの価数である。）

(In the formula, R ¹ is a direct bond, sulfur, alkylene having 1 to 9 carbon atoms or alkylidene having 2 to 9 carbon atoms, and R ² and R ³ are the same or different and are each hydrogen, and 8 alkyl or C 7-9 alkylaryl, M is Li, Na, K, Mg, Ca, Zn or Al, and n is the valence of M.)

Specific examples of the organometallic phosphate compound represented by the general formula (1) include sodium-2,2′-methylene-bis-(4,6-di-t-butylphenyl)phosphate, sodium-2 ,2'-ethylidene-bis-(4,6-di-t-butylphenyl) phosphate, sodium-2,2'-ethylidene-bis-(4-i-propyl-6-t-butylphenyl) phosphate , sodium-2,2′-butylidene-bis-(4,6-dimethylphenyl) phosphate, sodium-2,2′-butylidene-bis-(4,6-di-t-butylphenyl) phosphate, sodium -2,2'-t-octylmethylene-bis-(4,6-methylphenyl) phosphate, sodium-2,2'-t-octylmethylene-bis-(4,6-di-t-butylphenyl) Phosphate, Sodium-2,2'-methylene-bis-(4-methyl-6-t-butylphenyl)phosphate, Sodium-2,2'-methylene-bis-(4-ethyl-6-t-butyl phenyl) phosphate, sodium (4,4'-dimethyl-6,6'-di-t-butyl-2,2'-biphenyl) phosphate, sodium-2,2'-ethylidene-bis-(4-s -butyl-6-t-butylphenyl)phosphate, sodium-2,2'-methylene-bis-(4,6-di-methylphenyl)phosphate, sodium-2,2'-methylene-bis-(4 ,6-di-ethylphenyl) phosphate, lithium-2,2′-methylene-bis(4,6-di-t-butylphenyl) phosphate, lithium-2,2′-ethylidene-bis(4,6 -di-t-butylphenyl)phosphate, and mixtures of two or more thereof. Among these, sodium-2,2'-methylene-bis-(4,6-di-t-butylphenyl) phosphate and lithium-2,2'-methylene-bis(4,6-di-t- Butylphenyl)phosphate is preferred.
A commercially available product can be used as such a crystallization nucleating agent. Specific examples include ADEKA Corporation trade names: ADEKA STAB NA-11 and ADEKA STAB NA-71.

（式中、Ｒ^１は、水素又は炭素数１～４のアルキルであり、Ｒ^２及びＲ^３は、同一又は異なって、それぞれ水素又は炭素数１～１２のアルキルであり、Ｍは、周期表第１３族又は第１４族の金属であり、Ｘは、Ｍが周期表第１３族の金属である場合には、ＨＯ－であり、Ｍが周期表第１４族の金属である場合には、Ｏ＝又は（ＨＯ）_２－である。）

(In the formula, R ¹ is hydrogen or alkyl having 1 to 4 carbon atoms, R ² and R ³ are the same or different and each is hydrogen or alkyl having 1 to 12 carbon atoms, and M is the periodic table is a Group 13 or Group 14 metal, X is HO— if M is a Group 13 metal of the Periodic Table, and if M is a Group 14 metal of the Periodic Table, O= or (HO) ₂ -.)

Specific examples of aromatic phosphate esters represented by general formula (2) include, for example, hydroxyaluminum-bis[2,2′-methylene-bis(4,6-dimethylphenyl)phosphate], hydroxyaluminum- bis[2,2′-ethylidene-bis(4,6-dimethylphenyl)phosphate], hydroxyaluminum-bis[2,2′-methylene-bis(4,6-diethylphenyl)phosphate], hydroxyaluminum- bis[2,2′-ethylidene-bis(4,6-diethylphenyl)phosphate], hydroxyaluminum-bis[2,2′-methylene-bis(4,6-di-t-butylphenyl)phosphate] , and hydroxyaluminum-bis[2,2′-ethylidene-bis(4,6-di-t-butylphenyl)phosphate], hydroxyaluminum-bis[2,2′-methylene-bis(4-methyl-6 -t-butylphenyl)phosphate], hydroxyaluminum-bis[2,2′-ethylidene-bis(4-methyl-6-t-butylphenyl)phosphate], hydroxyaluminum-bis[2,2′-methylene -bis(4-ethyl-6-t-butylphenyl)phosphate], hydroxyaluminum-bis[2,2'-ethylidene-bis(4-ethyl-6-t-butylphenyl)phosphate], hydroxyaluminum- bis[2,2′-methylene-bis(4-i-propyl-6-t-butylphenyl)phosphate], hydroxyaluminum-bis[2,2′-ethylidene-bis(4-i-propyl-6- t-butylphenyl)phosphate] and the like, preferably hydroxyaluminum-bis[2,2′-methylene-bis(4,6-di-t-butylphenyl)phosphate] and hydroxyaluminum-bis Examples include [2,2′-ethylidene-bis(4,6-di-t-butylphenyl)phosphate] and mixtures of two or more thereof.

It is effective to use the aromatic phosphate represented by the general formula (2) together with an organic alkali metal salt.
The organic alkali metal salt can be at least one organic alkali metal salt selected from the group consisting of alkali metal carboxylates, alkali metal β-diketonates and alkali metal β-ketoacetic ester salts.
Lithium, sodium, potassium, etc. are mentioned as an alkali metal which comprises this organic alkali metal salt.
Examples of the carboxylic acid constituting the alkali metal carboxylate include acetic acid, propionic acid, acrylic acid, octylic acid, isooctyl acid, nonanoic acid, decanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, Ricinoleic acid, 12-hydroxystearic acid, behenic acid, montanic acid, melissic acid, β-dodecylmercaptoacetic acid, β-dodecylmercaptopropionic acid, β-N-laurylaminopropionic acid, β-N-methyl-lauroylaminopropionic acid Aliphatic polycarboxylic acids such as aliphatic monocarboxylic acids, malonic acid, succinic acid, adipic acid, maleic acid, azelaic acid, sebacic acid, dodecanedioic acid, citric acid, butanetricarboxylic acid, butanetetracarboxylic acid, naphthene acid, cyclopentanecarboxylic acid, 1-methylcyclopentanecarboxylic acid, 2-methylcyclopentanecarboxylic acid, cyclopentenecarboxylic acid, cyclohexanecarboxylic acid, 1-methylcyclohexanecarboxylic acid, 4-methylcyclohexanecarboxylic acid, 3,5-dimethyl Alicyclic mono- or polycarboxylic acids such as cyclohexanecarboxylic acid, 4-butylcyclohexanecarboxylic acid, 4-octylcyclohexanecarboxylic acid, cyclohexenecarboxylic acid, 4-cyclohexene-1,2-dicarboxylic acid, benzoic acid, toluic acid, xylyl acids, aromatic mono- or polycarboxylic acids such as ethylbenzoic acid, 4-t-butylbenzoic acid, salicylic acid, phthalic acid, trimellitic acid and pyromellitic acid.

Examples of the β-diketone compound constituting the alkali metal β-diketonate include acetylacetone, pivaloylacetone, palmitoylacetone, benzoylacetone, pivaloylbenzoylacetone, and dibenzoylmethane.

Examples of the β-ketoacetate constituting the alkali metal β-ketoacetate salt include ethyl acetoacetate, octyl acetoacetate, lauryl acetoacetate, stearyl acetoacetate, ethyl benzoylacetate, and lauryl benzoylacetate. be done.

The alkali metal carboxylate, alkali metal β-diketonate or alkali metal β-ketoacetate salt, which is a component of the organic alkali metal salt, can be combined with the above alkali metal and carboxylic acid, β-diketone compound or β-ketoacetate. and can be produced by a conventionally known method. Among these alkali metal salt compounds, aliphatic monocarboxylates of alkali metals, particularly aliphatic carboxylates of lithium are preferred, and aliphatic monocarboxylates having 8 to 20 carbon atoms are particularly preferred.

A commercially available product can be used as such a crystallization nucleating agent. Specifically, ADEKA Co., Ltd., trade name: ADEKA STAB NA-21 can be mentioned.

（式中、ｎは、０～２の整数であり、Ｒ^１～Ｒ^５は、それぞれ独立して、同一又は異なって、水素、ハロゲン、炭素数１～２０のアルキル、炭素数２～２０のアルケニル、炭素数１～２０のアルコキシ、炭素数１～２０のアルコキシカルボニル又はフェニルであり、Ｒ^６は、炭素数１～２０のアルキルである。ここで、アルキル、アルケニル、アルコキシ、アルコキシカルボニル及びフェニルは、ハロゲン等の置換基で置換されていてもよい。）

(In the formula, n is an integer of 0 to 2, and R ¹ to R ⁵ are each independently the same or different and are hydrogen, halogen, alkyl having 1 to 20 carbon atoms, alkenyl, alkoxy having 1 to 20 carbon atoms, alkoxycarbonyl having 1 to 20 carbon atoms or phenyl, and R ⁶ is alkyl having 1 to 20 carbon atoms, where alkyl, alkenyl, alkoxy, alkoxycarbonyl and phenyl may be substituted with a substituent such as halogen.)

Preferably, in general formula (3), n is an integer of 0 to 2, R ¹ , R ² , R ⁴ and R ⁵ are each hydrogen atoms, R ³ and R ⁶ are the same or different are alkyl groups having 1 to 20 carbon atoms.

More preferably, in formula (3), n is an integer of 0 to 2, R ¹ , R ² , R ⁴ and R ⁵ are each hydrogen atoms, and R ³ is —CH ₃ , —CH _{2CH 3} , -CH ₂ CH ₂ CH ₃ , -CH ₂ CH ₂ CH ₂ CH ₃ , -CH ₂ CH=CH ₂ , -CH(CH ₃ )CH=CH ₂ , -CH ₂ CHX ¹ -CH ₂ - X ² , -CH ₂ CHX ³ -CH ₂ CH ₃ , -CH ₂ CHX ⁴ -CH ₂ OH or -CH ₂ OH-CH(OH)-CH ₂ OH (provided that X ¹ to X ⁴ are each are independent halogen groups), and R ⁶ is preferably an alkyl group having 1 to 20 carbon atoms.

A commercially available product can be used as such a crystallization nucleating agent. Specifically, trade names: Milad NX8000 and Milad NX8000J manufactured by Milliken can be mentioned.

2. Characteristics: Blending amount of crystallization nucleating agent (K) The blending amount of the crystallization nucleating agent (K) is 100 parts by weight of the polypropylene-based resin mixture consisting of components (X), (Y), and (Z) (however, , (X), (Y), and (Z) are 100 parts by weight), preferably 0.02 to 0.8 parts by weight, more preferably 0 0.03 to 0.7 parts by weight, most preferably 0.05 to 0.6 parts by weight. When the amount of the crystallization nucleating agent (K) is within this range, the open cell ratio is improved, and various mechanical properties such as heat distortion resistance and foamability are well balanced.

3. Characteristics: Blending method of crystallization nucleating agent (K) 100 parts by weight of a polypropylene-based resin mixture consisting of components (X), (Y), and (Z) (wherein (X), (Y), and (Z) The total amount of the crystallization nucleating agent (K) is 100 parts by weight. It can also be added as When the crystallization nucleating agent (K) is added as a masterbatch, polypropylene or polyethylene having a melting peak temperature of less than 150° C. is often used in consideration of dispersion in a polypropylene mixture.

V. Constituents, preparation method, and uses of polypropylene resin composition 1. Constituent Components of Polypropylene Resin Composition Constituent components of a polypropylene resin composition suitable for foam molding are described in detail below.

(1) Foaming agent It is preferable to further add a foaming agent to the polypropylene-based resin composition of the present invention.
As the foaming agent, any publicly known foaming agent used for plastics, rubbers, etc. can be used without any problem. Conventionally used foaming agents such as physical foaming agents, decomposable foaming agents (chemical foaming agents), and microcapsules containing thermal expansion agents can be used.
Physical blowing agents include, for example, aliphatic hydrocarbons such as propane, butane, pentane and hexane, alicyclic hydrocarbons such as cyclopentane and cyclohexane, chlorodifluoromethane, difluoromethane, trifluoromethane, trichlorofluoromethane, and dichlorodifluoromethane. , chloromethane, dichloromethane, chloroethane, dichlorotrifluoroethane, dichlorofluoroethane, chlorodifluoroethane, dichloropentafluoroethane, tetrafluoroethane, difluoroethane, pentafluoroethane, trifluoroethane, trichlorotrifluoroethane, dichlorotetrafluoroethane, chloro Halogenated hydrocarbons such as pentafluoroethane and perfluorocyclobutane, water, carbon dioxide, and inorganic gases such as nitrogen can be used alone or in combination of two or more.
Among them, aliphatic hydrocarbons such as propane, butane, and pentane and carbon dioxide gas are preferable because they are inexpensive and highly soluble in the polypropylene resin (X). Carbon dioxide enters a supercritical state at 7.4 MPa or higher and 31° C. or higher, and is in a state of excellent diffusion and solubility in polymers.

When obtaining a polypropylene-based foam with a physical foaming agent, a cell regulator can be used as necessary. Examples of cell control agents include inorganic decomposable foaming agents such as ammonium carbonate, sodium bicarbonate, ammonium bicarbonate and ammonium nitrite; azo compounds such as azodicarbonamide, azobisisobutyronitrile and diazoaminobenzene; Nitroso compounds such as dinitrosopentane methylenetetramine and N,N'-dimethyl-N,N'-dinitrosoterephthalamide, benzenesulfonyl hydrazide, p-toluenesulfonyl hydrazide, p,p'-oxybisbenzenesulfonyl semicarbazide, p- Degradable blowing agents such as toluenesulfonyl semicarbazide, trihydrazinotriazine, barium azodicarboxylate, inorganic powders such as talc and silica, acid salts such as polyvalent carboxylic acids, reactions of polyvalent carboxylic acids with sodium carbonate or sodium bicarbonate mixtures, etc., and these can be used singly or in combination.

In addition, when obtaining a polypropylene-based foam with a decomposable foaming agent (chemical foaming agent), the decomposable foaming agent (chemical foaming agent) may be, for example, a mixture of sodium bicarbonate and an organic acid such as citric acid, azodicarbonamide , azo foaming agents such as barium azodicarboxylate, N,N'-dinitrosopentamethylenetetramine, nitroso foaming agents such as N,N'-dimethyl-N,N'-dinitrosoterephthalamide, p,p' -oxybisbenzenesulfonylhydrazide, p-toluenesulfonylsemicarbazide and other sulfohydrazide foaming agents, and trihydrazinotriazine.
The amount of the foaming agent to be blended is preferably in the range of 0.05 to 6.0 parts by weight, more preferably 0.05 to 6.0 parts by weight, per 100 parts by weight of components (X), (Y) and (Z) combined. 05 to 3.0 parts by weight, more preferably 0.5 to 2.5 parts by weight, particularly preferably 1.0 to 2.0 parts by weight.
When the blending amount of the foaming agent is 6.0 parts by weight or less, excessive foaming does not occur, and uniform fineness of the foam cells is facilitated. A large amount of gas is generated, which is preferable.
In addition, when using a cell control agent, the amount of the cell control agent is 0.01 to 0.01 in terms of pure content with respect to a total of 100 parts by weight of components (X), (Y), and (Z). A range of 5 parts by weight is preferred.

(2) Other Compounding Agents The polypropylene-based resin composition of the present invention contains the components (X), (Y), and (Z), the crystallization nucleating agent (K), and the foaming agent, if necessary. In addition to foam control agents, various additives such as other polymers, antioxidants, neutralizers, light stabilizers, ultraviolet absorbers, inorganic fillers, lubricants, antistatic agents, and metal deactivators are added. , can be blended within a range that does not impair the object of the present invention.
Other polymers include high-density polyethylene, low-density polyethylene, linear low-density polyethylene, polypropylene-based resins other than those listed above, propylene-α-olefin copolymers (α-olefin has 4 or more carbon atoms), poly -Polyolefins such as 4-methyl-1-pentene, olefinic elastomers such as ethylene-propylene elastomers, or other monomers copolymerizable therewith such as vinyl acetate, vinyl chloride, (meth)acrylic acid, (meth) ) copolymers such as acrylic acid esters, mixtures thereof, and the like.

Examples of antioxidants include phenol-based antioxidants, phosphite-based antioxidants, and thio-based antioxidants. Examples of neutralizing agents include higher fatty acid salts such as calcium stearate and zinc stearate. Examples of light stabilizers and ultraviolet absorbers include hindered amines, nickel complex compounds, benzotriazoles, benzophenones and the like.
Examples of inorganic fillers include talc, calcium carbonate, silica, hydrotalcite, zeolite, aluminum silicate and magnesium silicate, and examples of lubricants include higher fatty acid amides such as stearamide.
Examples of antistatic agents include fatty acid partial esters such as glycerin fatty acid monoesters, and examples of metal deactivators include triazines, phosphones, epoxies, triazoles, hydrazides, and oxamides. can.

2. Method for Preparing Polypropylene Resin Composition As a method for preparing the polypropylene resin composition of the present invention, the polypropylene resin (X) in powder or pellet form, the propylene block copolymer (Y), propylene-α-olefin A method of mixing the random copolymer (Z), the crystallization nucleating agent (K), the foaming agent, and optionally other compounding agents using a dry blend, a Henschel mixer (trade name), or the like can be used. . Alternatively, they may be melt-kneaded in advance using a single-screw kneader, a twin-screw kneader, a kneader, or the like. However, when the chemical foaming agent is simultaneously melt-kneaded, the kneading temperature must be controlled to a temperature lower than the decomposition temperature of the chemical foaming agent.
Depending on the situation, only the foaming agent may be separately fed during the production of the polypropylene-based foam.

3. Applications The polypropylene resin composition of the present invention can be used in various molding methods and applications that require high melt tension, such as injection molding (body), extrusion molding (body), bead foam molding (body), extrusion foam molding (body). ), injection foam molding (body), blow molding (body), injection blow molding (body), foam blow molding (body), deep drawing molding (body), thermoforming (body), etc. However, among others, it can be suitably used in the field of foam molding, where the superiority and inferiority of melt tension properties are most conspicuous.

4. Polypropylene resin (multilayer) foamed sheet The polypropylene resin foamed sheet obtained from the polypropylene resin composition (containing the foaming agent) of the present invention preferably has an average cell diameter of 500 µm or less, more preferably 400 µm or less, and more preferably 300 µm. More preferred are: An average cell diameter of 500 μm or less is preferable because appearance defects such as holes do not occur in both the polypropylene-based foamed sheet and the thermoformed article obtained by further thermoforming the sheet.
The polypropylene-based resin foamed sheet according to the present invention preferably has an open cell rate of 30% or less, more preferably 20% or less, still more preferably 15% or less, and particularly preferably 10% or less. An open cell ratio of 30% or less is preferable because expansion of the foam cells in the foam sheet occurs during thermoforming, thereby increasing the thickness of the thermoformed body. In addition, it is preferable because it leads to an improvement in the heat insulation performance of the thermoformed body.
The thickness of the foamed polypropylene resin sheet according to the present invention is not particularly limited, but is preferably about 0.3 mm to 10 mm. More preferably, it is 0.5 mm to 5 mm. The thickness of the foamed sheet formed by the T-die forming method is preferably about 0.3 mm to 3 mm, more preferably 0.5 mm to 2.0 mm.
The density of the polypropylene-based resin foamed sheet according to the present invention is not particularly limited. cm ³ or less, preferably 0.391 g/cm ³ or less, more preferably 0.300 g/cm ³ or less, still more preferably 0.265 g/cm ³ or less, most preferably 0.257 g/cm ³ or less. be.
The foaming ratio of the polypropylene-based resin foamed sheet according to the present invention is not particularly limited. 8 times or more, preferably 2.3 times or more, more preferably 3.0 times or more, particularly preferably 3.4 times or more, and most preferably 3.5 times or more. In particular, the polypropylene-based resin foamed sheet according to the present invention can achieve uniform and fine foamed cells even at a high expansion ratio of 3.0 times or more by the T-die method.

Examples of methods for obtaining a polypropylene resin foam sheet include molding methods such as injection molding, thermoforming, extrusion, blow molding, and bead foam molding. It can be obtained by a known extrusion molding method in which the composition is melted in an extruder and extruded through a die provided at the tip of the extruder. The extruder may be either a single-screw extruder or a twin-screw extruder, and may be, for example, a tandem system in which a twin-screw extruder and a single-screw extruder are combined in the front stage and rear stage.
In physical foaming, a physical foaming agent such as carbon dioxide gas or butane is introduced (injected) from the middle of the extruder cylinder. The die attached to the tip of the extruder may be a T die or a circular die.

Further, when a polypropylene-based resin multilayer foam sheet is formed, it can be obtained by co-extrusion molding a foamed layer made of a polypropylene-based resin composition and a non-foamed layer made of a thermoplastic resin composition.
The polypropylene-based resin multilayer foam sheet can be produced by a known co-extrusion method, extrusion lamination method, or the like using a feed block or multi-die using a plurality of extruders, but the co-extrusion method is preferred.
The non-foamed layer used in the polypropylene-based resin multilayer foamed sheet may be provided on either side of the foamed layer, and the foamed layer is present between two non-foamed layers (sandwich structure). can also
The polypropylene-based resin multilayer foamed sheet provided with the non-foamed layer has excellent strength, and at least the non-foamed layer provided on the outer side of the foamed layer provides excellent surface smoothness and appearance. Become. Furthermore, by using a functional thermoplastic resin for the non-foamed layer, it is possible to easily provide additional functions such as antibacterial properties, softness, and resistance to injury to the polypropylene-based resin multilayer foamed sheet. ,preferable.

As the thermoplastic resin constituting the thermoplastic resin composition used for the non-foamed layer, high-density polyethylene, low-density polyethylene, linear low-density polyethylene, component (X), Polyolefins such as polypropylene, propylene-α-olefin copolymers and poly-4-methyl-1-pentene, which may be the same as components (Y) and (Z), olefin-based elastomers such as ethylene-propylene elastomers , or other monomers copolymerizable with these, for example, copolymers such as vinyl acetate, vinyl chloride, (meth)acrylic acid, (meth)acrylic acid ester, and mixtures thereof. .
Among these, polypropylene and propylene-α-olefin copolymers are preferred in terms of recyclability, adhesiveness, heat resistance, oil resistance, rigidity, and the like. The propylene-α-olefin copolymer is a so-called impact-resistant polypropylene obtained by multistage polymerization of a propylene (co)polymer and an ethylene-propylene random copolymer using a plurality of or single polymerization tanks. Alternatively, it includes a multi-stage polymer commonly called a propylene block copolymer.

The thickness of the polypropylene-based resin multilayer foam sheet is not particularly limited, but is preferably about 0.3 mm to 10 mm. More preferably, it is 0.5 mm to 5 mm. The thickness of the foamed sheet formed by the T-die forming method is preferably about 0.3 mm to 3 mm, more preferably 0.5 mm to 2.0 mm.
In addition, the total thickness of the non-foamed layers in the polypropylene resin multilayer foam sheet should be 1 to 50%, more preferably 5 to 20%, of the total thickness of the resulting polypropylene resin multilayer foam sheet. is desirable. When the thickness of the non-foamed layer is 50% or less, the growth of cells in the foamed layer is not hindered.

Further, the polypropylene-based resin (multilayer) foam sheet according to the present invention can be used even if the surface of the foam sheet is subjected to surface treatment such as corona discharge treatment, flame treatment, plasma treatment, etc. for printability and paintability. It's okay.

5. Uses of Polypropylene Resin Foam Sheet and Thermoformed Product The polypropylene resin (multilayer) foam sheet according to the present invention and the molded product (thermoform) obtained by thermoforming the (multilayer) foam sheet have uniform and fine foam cells. It is excellent in appearance, thermoformability, impact resistance, lightness, rigidity, heat resistance, heat insulation, oil resistance, etc. It can be suitably used for vehicle interior materials such as mats, packaging, stationery, building materials, and the like.

EXAMPLES The present invention will be specifically described below by way of examples, but the present invention is not limited to these examples.
In the examples and comparative examples, the physical properties of the polypropylene resin composition, the polypropylene resin (multilayer) foam sheet, and their constituent components were measured and evaluated according to the following evaluation methods. I used the one from

1. Evaluation method (1) Melt flow rate MFR:
Measured according to JIS K7210:1999 Annex A Table 1, Condition M (230°C, 2.16 kg load). The die geometry is 2.095 mm in diameter and 8.000 mm in length. The unit is g/10 minutes.
(2) Melt tension MT:
Using a capilograph manufactured by Toyo Seiki Seisakusho Co., Ltd., measurements were made under the following conditions.
- Capillary: diameter 2.0 mm, length 40 mm
・Cylinder diameter: 9.55mm
・Cylinder extrusion speed: 20 mm/min ・Take-up speed: 4.0 m/min ・Temperature: 230°C
If the MT is extremely high, the resin may break at a take-up speed of 4.0 m/min. and Units are grams.
(3) molecular weight distribution Mw/Mn and Mz/Mn:
It was determined by GPC measurement according to the method described above.
(4) 25°C para-xylene soluble component content (CXS):
Measured by the method described in the specification.
(5) mm fraction:
Using GSX-400, FT-NMR manufactured by JEOL Ltd., as described above, it was measured by the method described in paragraphs [0053] to [0065] of JP-A-2009-275207.
The unit is %.

(6) Branching index g ^' :
As described above, it was determined by GPC equipped with a differential refractometer (RI), a viscosity detector (Viscometer), and a light scattering detector (MALLS) as detectors.
(7) Strain hardening degree λmax:
The extensional viscosity measurement was performed under the following conditions.
・Apparatus: Ares manufactured by Rheometrics
・ Jig: Extensional Viscosity Fixture manufactured by TA Instruments
・Measurement temperature: 180°C
・Strain rate: 0.1/sec
- Preparation of test piece: A sheet of 18 mm x 10 mm and a thickness of 0.7 mm is prepared by press molding.
The details of the method for calculating λmax are as described above.
(8) Melting peak temperature:
Using a differential scanning calorimeter (DSC), the temperature was once raised to 200°C to erase the thermal history, then the temperature was lowered to 40°C at a temperature drop rate of 10°C/min, and the temperature increase rate was again 10°C/min. The temperature of the endothermic peak top at the time of measurement was taken as the melting peak temperature.
(9) Ratio of (Y-1) and (Y-2), ethylene content in (Y-2):
It was determined by a combination of cross-fractionation and FT-IR methods described in the specification.
(10) Intrinsic viscosity of component (Y-2):
The CXS component of the propylene-based block copolymer (Y) was measured at a temperature of 135° C. using decalin as a solvent and using an Ubbelohde capillary viscometer. However, when the ethylene content of (Y-2) is less than 15% by weight, the intrinsic viscosity of the components (Y-1) and (Y) as a whole was measured and calculated according to the formula described in the specification.

(11) Density:
A test piece was cut out from the polypropylene-based resin (multilayer) foamed sheet obtained in Examples and Comparative Examples, and the weight (g) of the test piece was divided by the volume (cm ³ ) obtained from the external dimensions of the test piece. . The density was obtained by measuring according to JIS K7222.
(12) Foaming ratio:
It was obtained by dividing the density obtained in (11) by 0.900 g/cm ^{3 ,} which is the density of general non-foamed polypropylene.
(12) open cell rate:
Test pieces were cut out from the polypropylene-based resin (multilayer) foam sheets obtained in Examples and Comparative Examples, and measured using an air pycnometer (manufactured by Tokyo Science Co., Ltd.) according to the method described in ASTM D2856.
(13) Sheet appearance evaluation:
The appearance evaluation of the foamed sheet evaluated the polypropylene-based resin (multilayered) foamed sheets obtained in Examples and Comparative Examples according to the following criteria.
⊚: The shape of the air bubbles is fine and uniform, and the appearance of the sheet is beautiful.
◯: The shape of cells is uniform, and the appearance of the sheet is beautiful.
Δ: Cohesion of air bubbles is observed to some extent, and the appearance of the sheet is poor.
x: Remarkable coalescence of air bubbles, remarkably inferior sheet appearance.
(14) Drawdown resistance:
A test piece having a size of 300 mm×300 mm was cut out from the polypropylene-based resin (multilayer) foamed sheet obtained in Examples and Comparative Examples, and fixed to a frame having an inner dimension of 260 mm×260 mm. Using a sagging tester manufactured by Misuzu Elly Co., Ltd., the heaters are arranged vertically in a heating furnace in the tester, heated at an ambient temperature of 200 ° C., and the displacement of the central part of the sample from the start of heating is sequentially measured by a laser beam. It was measured.
As the sheet is heated, it once hangs down (displaced in the negative direction), stretches back due to stress relaxation (displaces in the positive direction), and then hangs up again. (mm), and the position 10 seconds after the maximum stretch back point B as C (mm), the drawdown resistance was evaluated according to the following criteria.
◎: BA ≥ 0 mm and CB ≥ -5 mm
○: BA ≥ -5 mm and CB ≥ -10 mm (excluding cases where BA ≥ 0 mm and CB ≥ -5 mm)
△: BA ≥ -5 mm and CB < -10 mm, or BA < -5 mm and CB ≥ -10 mm
×: BA <-5 mm and CB <-10 mm
Here, BA≧−5 mm means that the sheet is tense during container molding, and a wrinkle-free and beautiful appearance can be formed, and CB≧−10 mm is good. It means that the molding time range for obtaining a good container is sufficiently wide.

(15) Heat deformation resistance test of molded body A test piece with a size of 45 cm × 45 cm was cut out from the polypropylene resin (multilayer) foam sheet obtained in Examples and Comparative Examples, and a test vacuum and pressure molding machine (Asano Co., Ltd.) After heating both sides using a laboratory FKS type), a bowl-shaped container was formed by vacuum forming. Next, the resulting bowl-shaped container was impregnated in an oil bath heated to 130 ° C. (Nisshin Oilio Co., Ltd. Nisshin canola oil was used as the oil) for 5 minutes, then taken out and impregnated in the oil bath. Comparison of the container shape before and after was carried out according to the following criteria.
A: No difference in container shape before and after oil bath impregnation.
◯: Slight deformation of the container shape is observed after impregnation in the oil bath.
Δ: Significant shape deformation is observed after oil bath impregnation.
x: Significant deformation of the container shape is observed after impregnation in the oil bath.

2. Materials used (1) Polypropylene resin (X) having a long-chain branched structure
The polymer (PP-1) produced in Production Example 1 below and the polymer (PP-2) produced in Production Example 2 below were used.

[Production Example 1 (Production of PP-1)]
<Synthesis example 1 of catalyst component (A)>
Synthesis of dichloro[1,1′-dimethylsilylenebis{2-(5-methyl-2-furyl)-4-(4-i-propylphenyl)indenyl}]hafnium (component [A-1 ] (Synthesis of Complex 1)) was carried out.
(i) Synthesis of 4-(4-i-propylphenyl)indene In a 500 ml glass reaction vessel, 15 g (91 mmol) of 4-i-propylphenyl boronic acid and 200 ml of dimethoxyethane (DME) were added, and 90 g of cesium carbonate ( 0.28 mol) and 100 ml of water were added, 13 g (67 mmol) of 4-bromoindene and 5 g (4 mmol) of tetrakistriphenylphosphinopalladium were added in that order, and heated at 80° C. for 6 hours.
After standing to cool, the reaction mixture was poured into 500 ml of distilled water, transferred to a separating funnel, and extracted with diisopropyl ether. The ether layer was washed with saturated brine and dried over sodium sulfate. Sodium sulfate was filtered, the solvent was distilled off under reduced pressure, and the residue was purified with a silica gel column to obtain 15.4 g of 4-(4-i-propylphenyl)indene as a colorless liquid (yield 99%).

(ii) Synthesis of 2-bromo-4-(4-i-propylphenyl)indene 15.4 g (67 mmol) of 4-(4-i-propylphenyl)indene and 7.2 ml of distilled water were placed in a 500 ml glass reaction vessel. , 200 ml of DMSO was added, and 17 g (93 mmol) of N-bromosuccinimide was gradually added thereto. After stirring at room temperature for 2 hours, the reaction mixture was poured into 500 ml of ice water and extracted with 100 ml of toluene three times. The toluene layer was washed with saturated brine, 2 g (11 mmol) of p-toluenesulfonic acid was added, and the mixture was heated under reflux for 3 hours while removing moisture. After allowing the reaction mixture to cool, it was washed with saturated brine and dried over sodium sulfate. Sodium sulfate was filtered, the solvent was distilled off under reduced pressure, and the residue was purified with a silica gel column to obtain 19.8 g (yield 96%) of 2-bromo-4-(4-i-propylphenyl)indene as a yellow liquid. .

(iii) Synthesis of 2-(5-methyl-2-furyl)-4-(4-i-propylphenyl)indene 6.7 g (82 ml mol) of 2-methylfuran and 100 ml of DME were added to a 500 ml glass reaction vessel. was cooled to −70° C. with a dry ice-methanol bath. 51 ml (81 mmol) of a 1.59 mol/L n-butyllithium-n-hexane solution was added dropwise thereto, and the mixture was stirred for 3 hours. After cooling to −70° C., a solution of 20 ml (87 mmol) of triisopropylborate and 50 ml of DME was added dropwise. After dropping, the mixture was stirred overnight while the temperature was gradually returned to room temperature.
After adding 50 ml of distilled water to the reaction mixture for hydrolysis, a solution of 223 g of potassium carbonate and 100 ml of water and 19.8 g (63 mmol) of 2-bromo-4-(4-i-propylphenyl)indene were added in order, and the mixture was stirred at 80°C. The mixture was heated and reacted for 3 hours while removing low-boiling components.
After allowing to cool, the reaction mixture was poured into 300 ml of distilled water, transferred to a separating funnel and extracted three times with diisopropyl ether. The ether layer was washed with saturated brine and dried over sodium sulfate. Sodium sulfate is filtered, the solvent is distilled off under reduced pressure, and purification is performed with a silica gel column to obtain 19.6 g of colorless liquid of 2-(5-methyl-2-furyl)-4-(4-i-propylphenyl)indene ( Yield 99%) was obtained.

(iv) Synthesis of dimethylbis(2-(5-methyl-2-furyl)-4-(4-i-propylphenyl)indenyl)silane In a 500 ml glass reaction vessel, 2-(5-methyl-2- Furyl)-4-(4-i-propylphenyl)indene 9.1 g (29 mmol) and THF 200 ml were added and cooled to -70°C in a dry ice-methanol bath. 17 ml (28 mmol) of a 1.66 mol/L n-butyllithium-n-hexane solution was added dropwise thereto, and the mixture was stirred for 3 hours. After cooling to −70° C., 0.1 ml (2 mmol) of 1-methylimidazole and 1.8 g (14 mmol) of dimethyldichlorosilane were sequentially added, and the mixture was stirred overnight while the temperature was gradually returned to room temperature. Distilled water was added to the reaction mixture, the mixture was transferred to a separating funnel, washed with saline until neutral, and sodium sulfate was added to dry the reaction mixture. The sodium sulfate is filtered, the solvent is distilled off under reduced pressure, and the product is purified with a silica gel column to obtain a solution of dimethylbis(2-(5-methyl-2-furyl)-4-(4-i-propylphenyl)indenyl)silane. 8.6 g (88% yield) of a yellow solid were obtained.

(v) Synthesis of dichloro[1,1′-dimethylsilylenebis{2-(5-methyl-2-furyl)-4-(4-i-propylphenyl)indenyl}]hafnium In a 500 ml glass reaction vessel, Add 8.6 g (13 mmol) of dimethylbis(2-(5-methyl-2-furyl)-4-(4-i-propylphenyl)indenyl)silane and 300 ml of diethyl ether, and dry ice-methanol bath at -70°C. cooled to 15 ml (25 mmol) of 1.66 mol/L n-butyllithium-n-hexane solution was added dropwise thereto and stirred for 3 hours. The solvent of the reaction mixture was distilled off under reduced pressure, 400 ml of toluene and 40 ml of diethyl ether were added, and the mixture was cooled to -70°C in a dry ice-methanol bath. 4.0 g (13 mmol) of hafnium tetrachloride was added thereto. After that, the mixture was stirred overnight while the temperature was gradually returned to room temperature.
The solvent was distilled off under reduced pressure, recrystallization was performed with dichloromethane-hexane, and dichloro[1,1'-dimethylsilylenebis{2-(5-methyl-2-furyl)-4-(4-i-propylphenyl)indenyl }] 7.6 g (yield 65%) of racemic hafnium was obtained as yellow crystals.
Identification values by ¹ H-NMR for the obtained racemate are described below.
¹ H-NMR (C ₆ D ₆ ) identification results Racemate: δ0.95 (s, 6H), δ1.10 (d, 12H), δ2.08 (s, 6H), δ2.67 (m, 2H) , δ 5.80 (d, 2H), δ 6.37 (d, 2H), δ 6.74 (dd, 2H), δ 7.07 (d, 2H), δ 7.13 (d, 4H), δ 7.28 ( s, 2H), δ 7.30 (d, 2H), δ 7.83 (d, 4H).

<Synthesis Example 2 of Catalyst Component (A)>
Synthesis of rac-dichloro[1,1′-dimethylsilylenebis{2-methyl-4-(4-chlorophenyl)-4-hydroazulenyl}]hafnium: (Synthesis of component [A-2] (complex 2)):
Synthesis of rac-dichloro[1,1'-dimethylsilylenebis{2-methyl-4-(4-chlorophenyl)-4-hydroazulenyl}]hafnium is the method described in Example 1 of JP-A-11-240909. was carried out in the same manner as

<Catalyst Synthesis Example 1>
(i) Chemical treatment of ion-exchangeable layered silicate In a separable flask, 96% sulfuric acid (668 g) was added to 2,264 g of distilled water. 400 g of 19 μm particle size) were added. The slurry was heated at 90° C. for 210 minutes. After adding 4,000 g of distilled water to this reaction slurry, the mixture was filtered to obtain 810 g of a cake-like solid.
Next, 432 g of lithium sulfate and 1,924 g of distilled water were added to a separable flask to prepare an aqueous solution of lithium sulfate, and the whole cake-like solid was added. The slurry was allowed to react for 120 minutes at room temperature. After adding 4 L of distilled water to this slurry, the slurry was filtered, washed with distilled water to pH 5 to 6, and filtered to obtain 760 g of a cake-like solid.
The obtained solid was pre-dried at 100° C. under a nitrogen stream for one day and night, then coarse particles with a diameter of 53 μm or more were removed, and further dried under reduced pressure at 200° C. for 2 hours to obtain 220 g of chemically treated smectite.
The composition of this chemically treated smectite is Al: 6.45 wt%, Si: 38.30 wt%, Mg: 0.98 wt%, Fe: 1.88 wt%, Li: 0.16 wt%, Al/Si=0.175 [mol/mol].

(ii) Catalyst preparation and prepolymerization Into a three-necked flask (1 L volume), 20 g of the chemically treated smectite obtained above was placed, heptane (132 mL) was added to form a slurry, and triisobutylaluminum (25 mmol: concentration 68.0 mL of a 143 mg/mL heptane solution) was added, stirred for 1 hour, washed with heptane until the residual liquid ratio became 1/100 or less, and heptane was added so that the total liquid volume was 100 mL.
In another flask (volume: 200 mL), rac-dichloro[1,1′-dimethylsilylenebis{2-(5-methyl-2-furyl)- 4-(4-i-Propylphenyl)indenyl}]hafnium (210 μmol) was dissolved in toluene (42 mL) (solution 1), and in another flask (volume: 200 mL), the catalyst component (A) was synthesized. rac-dichloro[1,1′-dimethylsilylenebis{2-methyl-4-(4-chlorophenyl)-4-hydroazulenyl}]hafnium (90 μmol) prepared in Example 2 was dissolved in toluene (18 mL) (Solution 2 ).
After adding triisobutylaluminum (0.84 mmol: 1.2 mL of a heptane solution with a concentration of 143 mg/mL) to the 1 L flask containing the chemically treated smectite, the above solution 1 was added and stirred at room temperature for 20 minutes. After that, triisobutylaluminum (0.36 mmol: 0.50 mL of a heptane solution with a concentration of 143 mg/mL) was further added, and then the above solution 2 was added, followed by stirring at room temperature for 1 hour.
An additional 338 mL of heptane was then added and the slurry was introduced into a 1 L autoclave.
After the internal temperature of the autoclave was adjusted to 40° C., propylene was fed at a rate of 10 g/hour, and prepolymerization was carried out while maintaining the temperature at 40° C. for 4 hours. After that, the propylene feed was stopped and residual polymerization was carried out for 1 hour. After removing the supernatant of the resulting catalyst slurry by decantation, triisobutylaluminum (6 mmol: 17.0 mL of a heptane solution having a concentration of 143 mg/mL) was added to the remaining portion and stirred for 5 minutes.
This solid was dried under reduced pressure for 1 hour to obtain 52.8 g of a dry prepolymerized catalyst. The prepolymerization ratio (value obtained by dividing the amount of prepolymerized polymer by the amount of solid catalyst) was 1.64.
Hereinafter, this catalyst is referred to as "prepolymerization catalyst 1".

<Polymerization>
After the inside of the stirring autoclave having an internal volume of 200 liters was sufficiently replaced with propylene, 40 kg of sufficiently dehydrated liquefied propylene was introduced. After adding 9.5 liters of hydrogen (as a standard volume) and 470 ml (0.12 mol) of triisobutylaluminum/n-heptane solution, the internal temperature was raised to 70°C. Then, 1.9 g of prepolymerized catalyst 1 (by weight excluding the prepolymerized polymer) was injected with argon to initiate polymerization and the internal temperature was maintained at 70°C. After 2 hours had passed, 100 ml of ethanol was pressurized to purge unreacted propylene, and the inside of the autoclave was replaced with nitrogen to terminate the polymerization.
The resulting polymer was dried at 90° C. under a nitrogen stream for 1 hour to obtain 18.4 kg of polymer (hereinafter referred to as “PP-1”).
The catalytic activity was 9200 (g-PP/g-cat). MFR was 9.3 g/10 minutes.

[Production Example 2 (Production of PP-2)]
The procedure was carried out in the same manner as in Production Example 1, except that 4.8 liters of hydrogen was added and 2.3 g of prepolymerization catalyst 1 was used (by weight excluding the prepolymerization polymer). 16.1 kg of polymer (hereinafter referred to as "PP-2") was obtained.
The catalytic activity was 6980 (g-PP/g-cat). MFR was 1.9 g/10 minutes.

[Production of PP-1 to PP-2 pellets (X1) to (X2)]
Tetrakis[methylene-3-(3′,5′-di-t -Butyl-4'-hydroxyphenyl)propionate]methane (trade name: IRGANOX1010, manufactured by BASF Japan Ltd.) 0.125 parts by weight, tris (2,4-di-t), a phosphite antioxidant -Butylphenyl) phosphite (trade name: IRGAFOS 168, manufactured by BASF Japan Co., Ltd.) is blended with 0.125 parts by weight, and mixed for 3 minutes at room temperature using a high-speed stirring mixer (Henschel mixer, trade name). After that, the mixture was melt-kneaded with a twin-screw extruder to obtain pellets (X1) to (X2) of the polypropylene resin (X).
The twin-screw extruder is Technobel KZW-25, the screw rotation speed is 400 RPM, and the kneading temperature is set to 80, 160, 210, 230 from the bottom of the hopper (the same temperature until the die exit) ° C. did.
The obtained pellets (X1) to (X2) were evaluated for MFR, CXS, ¹³ C-NMR, GPC, branching index, MT and extensional viscosity. The evaluation results are shown in Table 1.

(2) Propylene block copolymer (Y)
A propylene-based block copolymer (Y1) produced in Production Example 3 below was used.

[Production Example 3: Production of propylene-based block copolymer (Y1)]
<Catalyst analysis method>
The following methods were used for analysis of catalyst components, solid catalysts, and prepolymerized catalysts.
- Ti content (wt%) A sample was accurately weighed, hydrolyzed, and then measured using a colorimetric method. For samples after prepolymerization, the content was calculated using the weight excluding the prepolymerized polymer.
・ Silicon compound content (wt%)
Samples were accurately weighed and digested with methanol. The silicon compound concentration in the resulting methanol solution was determined by comparison with a standard sample using gas chromatography. The silicon compound content in the sample was calculated from the silicon compound concentration in methanol and the weight of the sample. For samples after prepolymerization, the content was calculated using the weight excluding the prepolymerized polymer.

<Preparation of prepolymerized catalyst B1>
(1) Preparation of Solid Component B1 A 10-liter autoclave equipped with a stirring device was sufficiently purged with nitrogen, and 2 liters of purified toluene was introduced. At room temperature, 200 g of Mg(OEt) ₂ was added thereto, and 1 L of TiCl ₄ was slowly added. The temperature was gradually raised to 90° C. and 50 ml of di-n-butyl phthalate were introduced. After that, the temperature was raised to 110° C. and the reaction was carried out for 3 hours. The reaction mixture was thoroughly washed with purified toluene. Next, refined toluene was introduced to adjust the total liquid volume to 2 L. 1 L of TiCl ₄ was added at room temperature and the temperature was raised to 110° C. for 2 hours of reaction. The reaction mixture was thoroughly washed with purified toluene. Next, refined toluene was introduced to adjust the total liquid volume to 2 L. 1 L of TiCl ₄ was added at room temperature and the temperature was raised to 110° C. for 2 hours of reaction. The reaction mixture was thoroughly washed with purified toluene. Furthermore, purified n-heptane was used to replace toluene with n-heptane to obtain a slurry of solid component B1. A portion of this slurry was sampled and dried. An analysis revealed that the Ti content of solid component B1 was 2.7 wt %.

(2) Preparation of Solid Catalyst B1 Next, a 20-liter autoclave equipped with a stirring device was sufficiently purged with nitrogen, and 100 g of the solid component B1 slurry was introduced as a solid component. Purified n-heptane was introduced to adjust the solid component concentration to 25 g/L. 50 ml of SiCl ₄ was added and reacted at 90° C. for 1 hour. The reaction mixture was thoroughly washed with purified n-heptane.
Thereafter, purified n-heptane was introduced to adjust the liquid level to 4L. 30 ml of dimethyldivinylsilane, 30 ml of t-BuMeSi(OMe) ₂ and 80 g of Et ₃ Al diluted in n-heptane of Et ₃ Al were added, and reaction was carried out at 40° C. for 2 hours. The reaction mixture was thoroughly washed with purified n-heptane to obtain solid catalyst B1 formed by organosilicon treatment of solid component B1. A part of the obtained solid catalyst B1 slurry was sampled, dried and analyzed. Solid catalyst B1 contained 1.2 wt % Ti and 8.9 wt % t-BuMeSi(OMe) ₂ .

(3) Preliminary polymerization Using the solid catalyst B1 obtained above, preliminary polymerization was performed according to the following procedure. Refined n-heptane was introduced into the above slurry to adjust the solid catalyst concentration to 20 g/L. After cooling the slurry to 10° C., 10 g of Et ₃ Al diluted in n-heptane was added as Et ₃ Al, and 280 g of propylene was fed over 4 hours. After the supply of propylene was finished, the reaction was continued for another 30 minutes. Then, the gas phase was thoroughly purged with nitrogen, and the reaction mixture was thoroughly washed with purified n-heptane. The obtained slurry was extracted from the autoclave and dried in a vacuum to obtain a prepolymerized catalyst B1. This prepolymerized catalyst B1 contained 2.5 g of polypropylene per 1 g of solid catalyst. Analysis revealed that the portion of the prepolymerized catalyst B1 excluding the polypropylene contained 1.0 wt % of Ti and 8.3 wt % of t-BuMeSi(OMe) ₂ .

Polymerization was carried out using a two-tank continuous gas phase polymerization reactor. Both the first polymerization tank in which the first step of the sequential polymerization is performed and the second polymerization tank in which the second step is performed are fluidized bed reactors having an internal volume of 230 liters. The raw material gas used was sufficiently purified.

(First step: production of propylene polymer)
Regarding the gas composition of the first polymerization tank, propylene and nitrogen were continuously supplied so that the partial pressure of propylene was 1.8 MPaA and the total pressure of the polymerization tank was 3.0 MPaG. Further, hydrogen as a molecular weight control agent was continuously supplied so that the molar ratio of hydrogen/propylene was 0.020. The polymerization temperature was controlled to 60°C. Et ₃ Al was supplied to the first polymerization tank at 4.0 g/h, and the prepolymerization catalyst B1 was added to the first polymerization tank so that the production rate of the propylene polymer in the first polymerization tank was 17.5 kg/h. A propylene homopolymer was produced by continuously supplying it. The powder (propylene polymer) produced in the first polymerization tank was continuously extracted so that the amount of powder held in the polymerization tank was 40 kg, and was continuously transferred to the second polymerization tank. A portion of the powder transferred from the first polymerization tank to the second polymerization tank was sampled and analyzed, and the MFR was found to be 20.0 g/10 minutes. When measuring the MFR, the sample propylene polymer was added to tetrakis[methylene-3-(3′,5′-di-t-butyl-4′-hydroxyphenyl)propionate]methane (product Name: IRGANOX1010, manufactured by BASF Japan Ltd.), tris (2,4-di-t-butylphenyl) phosphite (trade name: IRGAFOS 168, manufactured by BASF Japan Ltd.), and calcium stearate in appropriate amounts (500 wtppm). In order to add them, they were placed in a plastic bag, and the bag was shaken up and down and right and left by hand to thoroughly mix the contents (dry blend), and then the measurement was carried out.
MPaG is a gauge pressure based on atmospheric pressure, and has a relationship of XX [MPaG]=XX+0.10133 [MPaA] with MPaA (absolute pressure) based on vacuum pressure.

(Second step: production of propylene-ethylene copolymer)
Regarding the gas composition of the second polymerization tank, propylene, ethylene and nitrogen were continuously supplied so that the partial pressure of propylene was 1.15 MPaA, the partial pressure of ethylene was 0.35 MPaA, and the total pressure of the polymerization tank was 2.5 MPaG. effectively supplied. Further, hydrogen was continuously supplied as a molecular weight control agent so that the molar ratio of hydrogen/(propylene+ethylene) was 260 ppm. The polymerization temperature was controlled to 70°C. Furthermore, as a polymerization inhibitor, ethanol was continuously supplied at a rate of 2.0 g/h to produce a propylene-ethylene copolymer. The powder (propylene-based block copolymer, which is a multi-stage polymer consisting of a propylene polymer and a propylene-ethylene copolymer) that has been produced in the second polymerization tank is kept in such a way that the amount of powder held in the polymerization tank is 60 kg. continuously withdrawn into the vessel. Nitrogen gas containing water was supplied to this vessel to terminate the reaction, thereby obtaining a propylene-based block copolymer (Y1).

[Production of propylene-based block copolymer (Y) pellets]
1,3,5-tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate ( Trade name: Cyanox 1790, manufactured by Nippon Cytec Industries Co., Ltd.) 0.05 parts by weight, tris(2,4-di-t-butylphenyl)phosphite (trade name: IRGAFOS 168, manufactured by BASF Japan Ltd.) 0.05 parts by weight. 10 parts by weight and 0.05 part by weight of calcium stearate were blended and mixed at room temperature for 3 minutes using a high-speed mixer (Henschel mixer, trade name). Thereafter, the mixture was melt-kneaded and extruded by a twin-screw extruder, passed through a cold water tank, and then cut into strands by a strand cutter to obtain pellets.
In addition, KZW-25 manufactured by Technovel Co., Ltd. is used for the twin-screw extruder, the screw rotation speed is 300 RPM, and the kneading temperature is 80, 160, 180, 200, 200, 200, 210, 210, 210 ° C. from the bottom of the hopper (die exit).
As a result of analyzing the pellets of the obtained propylene-based block copolymer (Y1), the MFR was 1.2 g/10 minutes, and the propylene-ethylene copolymer (Y-2) in the propylene-based block copolymer (Y) content is 28.0% by weight, the ethylene content in the propylene-ethylene copolymer (Y-2) is 26.0% by weight, the melting peak temperature of the propylene-based block copolymer (Y) is 160.0°C, Propylene-ethylene copolymer (Y-2) had an intrinsic viscosity of 9.4 dl/g.
The pellets of the propylene-based block copolymer (Y1) are also referred to as component (Y) pellets (Y1).

(3) Propylene-α-olefin random copolymer (Z)
A commercially available grade can be used as the propylene-α-olefin random copolymer (Z) of the present invention.
(Z1) Novatec PP MG03BF (trade name, manufactured by Japan Polypropylene Corporation), catalyst: Ziegler-Natta catalyst, melting peak temperature: 148°C, MFR: 30 g/10 minutes (Z2) Novatec PP MG03EQ (trade name, Japan Polypropylene) Co., Ltd.), catalyst: Ziegler-Natta catalyst, melting peak temperature: 144° C., MFR: 30 g/10 minutes)
(Z3) Novatec PP MG3F (trade name, manufactured by Japan Polypropylene Corporation), catalyst: Ziegler-Natta catalyst, melting peak temperature: 152°C, MFR: 8 g/10 minutes

(4) Propylene homopolymer (H1) Novatec PP MA1B (trade name, manufactured by Japan Polypropylene Corporation), catalyst: Ziegler-Natta catalyst, melting peak temperature: 158°C, MFR: 20 g/10 minutes

(5) Master batch (K1) of crystallization nucleating agent (K) MBN05A (trade name, manufactured by Japan Polypropylene Corporation), manufactured by ADEKA Co., Ltd., trade name: crystallization nuclei containing ADEKA STAB NA-11 at 5% by weight Agent master batch (K2) MBN05B (trade name, manufactured by Japan Polypropylene Corporation), manufactured by ADEKA Co., Ltd., trade name: crystallization nucleating agent master batch (K3) STX0691D (trade name, containing 5% by weight of ADEKA STAB NA-21) , manufactured by Japan Polypropylene Corporation), manufactured by Miliken, trade name: crystallization nucleating agent masterbatch containing 10% by weight of MIRAD NX8000J

[Example 1]
In order to obtain a foamed layer, a mixture 100 in which the weight ratio of the pellets (X1) of the component (X), the pellets (Y1) of the component (Y), and the pellets (Z1) of the component (Z) was 35:15:50 parts by weight, 2 parts by weight of masterbatch (K1) of crystallization nucleating agent (K), chemical foaming agent (trade name: Hydrocerol CF40E-J, manufactured by Nippon Boehringer Ingelheim Co., Ltd.) as cell adjusting agent, 0. 5 parts by weight were uniformly stirred and mixed with a ribbon blender, and charged into an extruder with a screw diameter of 65 mmΦ having a barrel hole for injecting a physical foaming agent in the middle of the barrel.
The cylinder setting temperature of the extruder is 250° C. and the screw rotation speed is 105 rpm. 45 parts by weight of the mixture was press-fitted and kneaded to obtain a polypropylene-based resin composition for foam molding.
After the extruder, the polypropylene resin composition for foam molding was cooled to a final resin temperature of 205°C.
In addition, in order to obtain a non-foamed layer, a propylene-ethylene block copolymer resin (trade name: Novatec PP, grade name “BC3BRFA”, grade name “BC3BRFA”, MFR = 13 g/10 min. ) 100 parts by weight of a thermoplastic resin composition is charged, heated and melted at 220 ° C., cooled to 180 ° C., and passed through a feed block with the polypropylene resin composition for foam molding to a T-die (gap = 0.4 mm) were coextruded in air at a rate of 83 kg/hr in a two-kind, three-layer structure consisting of a non-foamed layer, a foamed layer, and a non-foamed layer to obtain a polypropylene-based resin multilayer foamed sheet.
While the foam was cooled by a cooling roll and an air knife, it was stretched by pinch roll take-up to adjust the thickness to form a foamed sheet having a thickness of 1.50 mm.
The resulting multilayer foam sheet had a layer structure of non-foamed layer:foamed layer:non-foamed layer with a thickness of 3.2:93.6:3.2, a density of 0.259 g/cm ³ , and a continuous It had a good appearance with a void content of 11.5%. Table 2 shows the evaluation results of the foam sheet.

[Example 2]
First, in order to pelletize the powder of component (Z2), tetrakis[methylene-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]methane (trade name: 100 parts by weight of component (Z2)) IRGANOX 1010, manufactured by BASF Japan Ltd.) 0.10 parts by weight, tris (2,4-di-t-butylphenyl) phosphite (trade name: IRGAFOS 168, manufactured by BASF Japan Ltd.) 0.10 parts by weight , and 0.05 parts by weight of calcium stearate were mixed at room temperature for 3 minutes using a high-speed stirring mixer (Henschel mixer, trade name). Thereafter, the mixture was melt-kneaded and extruded by a twin-screw extruder, passed through a cold water tank, and then cut into strands by a strand cutter to obtain pellets.
In addition, KZW-25 manufactured by Technovel Co., Ltd. is used for the twin-screw extruder, the screw rotation speed is 300 RPM, and the kneading temperature is 80, 160, 180, 200, 200, 200, 210, 210, 210 ° C. from the bottom of the hopper (die exit).
Then, 100 parts by weight of a mixture in which the weight ratio of the pellets (X1) of the component (X), the pellets (Y1) of the component (Y), and the obtained pellets of the component (Z2) is 35:15:50, and crystals 2 parts by weight of the masterbatch (K1) of the nucleating agent (K) and 0.5 parts by weight of the chemical foaming agent described in Example 1 as a cell control agent were mixed, and the same method as described in Example 1 was performed. , a multilayer foam sheet was produced. Table 2 shows the evaluation results of the obtained foamed sheet.

[Examples 3-4]
Pellets of component (X), component (Y) and component (Z) in the types and weight ratios shown in Table 2 and a masterbatch of crystallization nucleating agent (K), and the chemical described in Example 1 as a cell control agent A multilayer foam sheet was produced in the same manner as in Example 1 by mixing with 0.5 parts by weight of a foaming agent. Table 2 shows the evaluation results of the obtained foamed sheet.

[Comparative Example 1]
In order to obtain a foamed layer, 100 parts by weight of a mixture of only pellets (X1) of component (X) and pellets (Y1) of component (Y) at a weight ratio of 70:30, and a master of crystallization nucleating agent (K) A foamed sheet was obtained in the same manner as in Example 1, except that 2 parts by weight of batch (K1) and 0.5 parts by weight of a chemical foaming agent as a cell regulator were used. The foamed sheet had a remarkably high open cell ratio and poor appearance.

[Comparative Example 2]
In order to obtain a foamed layer, pellets (X1) of component (X), pellets (Y1) of component (Y) and pellets of propylene-α-olefin random copolymer (Z) outside the scope of the claims of the present application A foam sheet was obtained in the same manner as described in Example 1, except that (Z3) was used at a weight ratio of 35:15:50. The foamed sheet had a remarkably high open cell ratio, was inferior in the appearance of the sheet, and failed to reach the target in sheet thickness and expansion ratio. Regarding this, it is considered that the independence of the sheet is extremely low, so that carbon dioxide dissipates from the surface of the sheet into the atmosphere during foaming, and the sheet thickness and foaming ratio cannot be increased.

[Comparative Example 3]
In order to obtain a foamed layer, pellets (X1) of component (X), pellets (Y1) of component (Y) and polypropylene homopolymer pellets (H1) outside the scope of the claims of the present application were mixed in a weight ratio of 35: Example 1 except that 100 parts by weight of a 15:50 mixture, 2 parts by weight of a masterbatch (K1) of a crystallization nucleating agent (K), and 0.5 parts by weight of a chemical foaming agent as a cell control agent were used. A foam sheet was obtained in the same manner as described in . The foamed sheet had a remarkably high open cell ratio, was inferior in the appearance of the sheet, and failed to reach the target in sheet thickness and expansion ratio. Regarding this, it is considered that the independence of the sheet is extremely low, so that carbon dioxide dissipates from the surface of the sheet into the atmosphere during foaming, and the sheet thickness and foaming ratio cannot be increased.

[Comparative Example 4]
A foamed sheet was obtained in the same manner as described in Example 1, except that the masterbatch (K1) of the crystallization nucleating agent (K) was not formulated. The foam sheet had a high open cell ratio and poor heat deformation resistance as a molded product.

[Comparative Example 5]
A foamed sheet was obtained in the same manner as described in Example 2, except that the masterbatch (K1) of the crystallization nucleating agent (K) was not formulated. The foamed sheet had a high open cell ratio and poor heat deformation resistance as a molded product.

[Examples 5-6]
Pellets of component (X), component (Y) and component (Z) in the types and weight ratios shown in Table 3 and a masterbatch of crystallization nucleating agent (K), and the chemical described in Example 1 as a cell control agent A multilayer foam sheet was produced in the same manner as in Example 1 by mixing with 0.75 parts by weight of a foaming agent. In Examples 5 and 6, the thickness of the multilayer foam sheet was changed to the value shown in Table 3. Table 3 shows the evaluation results of the obtained foamed sheet.

The polypropylene-based resin composition of the present invention, the polypropylene-based resin (multilayer) foamed sheet obtained therefrom, and the thermoformed article using the foamed sheet have uniform and fine foamed cells, and have good appearance, thermoformability, and impact resistance. Due to its excellent lightness, rigidity, heat resistance, heat insulation, oil resistance, etc., it is used for food containers such as trays, plates and cups, vehicle interior materials such as automobile door trims and automobile trunk mats, packaging, stationery, building materials, etc. It can be suitably used for various purposes, and its industrial value is extremely high.

Claims (10)

67.5 to 2.5 parts by weight of a polypropylene resin (X) having the following properties (Xi) to (Xiv) and having a long-chain branched structure;
Propylene which is a multi-stage polymer consisting of a propylene (co)polymer (Y-1) and a propylene-ethylene copolymer (Y-2) and having the following properties (Yi) to (Yv) 2.5 to 67.5 parts by weight of a system block copolymer (Y), and a propylene-α-olefin random copolymer (Z) having the following characteristics (Zi) to (Z-iii) 100 parts by weight of a polypropylene resin mixture containing 10 to 75 parts by weight (where the total of (X), (Y) and (Z) is 100 parts by weight), and 0.00 part of the crystallization nucleating agent (K) is added. 01 to 1.0 parts by weight of a polypropylene resin composition.
(Xi) MFR is 0.1 to 30.0 g/10 minutes. Here, MFR is JIS K7210: 1999 "Plastics - Test methods for melt mass flow rate (MFR) and melt volume flow rate (MVR) of thermoplastics" Annex A Table 1, condition M (230 ° C., 2. 16 kg load).
(X-ii) The molecular weight distribution Mw/Mn measured by GPC is 3.0 to 10.0, and the Mz/Mw is 2.5 to 10.0.
(X-iii) Melt tension (MT) (unit: g) is
log(MT)≧−0.9×log(MFR)+0.7, or MT≧15
satisfy any of Here, the melt tension (MT) is as follows: capillary: diameter 2.0 mm, length 40 mm, cylinder diameter: 9.55 mm, cylinder extrusion speed: 20 mm/min, take-up speed: 4.0 m/min, temperature: 230°C. condition represents the melt tension when measured. However, if the resin is broken at the take-up speed of 4.0 m/min, the take-up speed is reduced and the tension at the maximum speed at which the take-up is possible is defined as MT. The method for measuring MFR is as described in (Xi).
(X-iv) The 25°C para-xylene soluble component content (CXS) is less than 5.0% by weight relative to the total weight of the polypropylene resin (X).
(Yi) The ratio of (Y-1) and (Y-2) is such that (Y-1) is 50 to 99% by weight and (Y-2) is 1 to 50% by weight (provided that propylene The total weight of the system block copolymer (Y) is 100% by weight).
(Y-ii) MFR of the propylene-based block copolymer (Y) is 0.1 to 200.0 g/10 minutes. Here, MFR is JIS K7210: 1999 "Plastics - Test methods for melt mass flow rate (MFR) and melt volume flow rate (MVR) of thermoplastics" Annex A Table 1, condition M (230 ° C., 2. 16 kg load).
(Y-iii) The melting peak temperature of the propylene-based block copolymer (Y) exceeds 155°C.
(Y-iv) The ethylene content in the propylene-ethylene copolymer (Y-2) is 11 to 60% by weight (provided that the total weight of the constituent monomers of the propylene-ethylene copolymer (Y-2) is 100% by weight).
(Yv) The intrinsic viscosity of the propylene-ethylene copolymer (Y-2) in decalin at 135°C is 5.3 dl/g or more.
(Zi) Polymerized with a Ziegler-Natta catalyst.
(Z-ii) The melting peak temperature measured by DSC is 157° C. or lower.
(Z-iii) MFR is 21.0 g/10 minutes or more. Here, MFR is JIS K7210: 1999 "Plastics - Test methods for melt mass flow rate (MFR) and melt volume flow rate (MVR) of thermoplastics" Annex A Table 1, condition M (230 ° C., 2. 16 kg load). 2. The polypropylene-based resin composition according to claim 1, wherein the polypropylene resin (X) has the following properties (Xv).
(Xv): The branching index g ^' at an absolute molecular weight Mabs of 1,000,000 is 0.30 or more and less than 0.95. 3. The polypropylene resin composition according to claim 2, wherein the polypropylene resin (X) has the following properties (X-vi).
(X-vi): The mm fraction of 3 chains of propylene units determined by ¹³ C-NMR is 95% or more. The polypropylene resin composition according to any one of claims 1 to 3, wherein the crystallization nucleating agent (K) is represented by the following general formulas (1) to (2).

(In the formula, R ¹ is a direct bond, sulfur, alkylene having 1 to 9 carbon atoms or alkylidene having 2 to 9 carbon atoms, and R ² and R ³ are the same or different and are each hydrogen, and 8 alkyl or C 7-9 alkylaryl, M is Li, Na, K, Mg, Ca, Zn or Al, and n is the valence of M.)

(In the formula, R ¹ is hydrogen or alkyl having 1 to 4 carbon atoms, R ² and R ³ are the same or different and each is hydrogen or alkyl having 1 to 12 carbon atoms, and M is the periodic table is a Group 13 or Group 14 metal, X is HO— if M is a Group 13 metal of the Periodic Table, and if M is a Group 14 metal of the Periodic Table, O= or (HO) ₂ -.) The polypropylene resin composition according to any one of claims 1 to 3, wherein the crystallization nucleating agent (K) is represented by the following general formula (3).
(In the formula, n is an integer of 0 to 2, and R ¹ to R ⁵ are each independently the same or different and are hydrogen, halogen, alkyl having 1 to 20 carbon atoms, alkenyl, alkoxy having 1 to 20 carbon atoms, alkoxycarbonyl having 1 to 20 carbon atoms or phenyl, and R ⁶ is alkyl having 1 to 20 carbon atoms.) The polypropylene resin composition according to any one of claims 1 to 5, characterized by containing 0.05 to 6.0 parts by weight of a foaming agent with respect to 100 parts by weight of the polypropylene resin mixture. A polypropylene resin composition for foam molding. A foamed polypropylene resin sheet obtained by extruding the polypropylene resin composition for foam molding according to claim 6 . A multilayer polypropylene resin foam sheet obtained by coextrusion of the polypropylene resin foam sheet according to claim 7 and a non-foamed layer made of a thermoplastic resin composition. A molded product obtained by thermoforming the polypropylene-based resin foamed sheet according to claim 7 or the multilayer foamed sheet according to claim 8. The polypropylene resin composition according to any one of claims 1 to 5 or the polypropylene resin composition for foam molding according to claim 6 is subjected to an injection molding method, a thermoforming method, an extrusion molding method, a blow molding method or a bead A molded article characterized by being obtained by molding by any one of foam molding methods.