JP6481279B2 - Polypropylene resin composition for sealant and film comprising the same - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a polypropylene resin composition for a sealant and a polypropylene film, and more specifically, a polypropylene resin composition for a sealant excellent in fusing sealability and cleanliness (stickiness, bleed out, low elution components, etc.) and a polypropylene resin. Related to film.

Conventionally, biaxially oriented polypropylene films have excellent transparency and rigidity, and can be heat-sealed at low temperatures by multilayering by coextrusion molding. Yes.
As the polypropylene resin (PP) used for the sealing layer, a Ziegler PP has been conventionally proposed. However, cleanliness (stickiness, bleedout, residual volatile content, etc.) is inferior, and thus excellent cleanliness. Metallocene PP is desired.
However, when the metallocene PP is used for the fusing seal layer, there is a problem that the fusing heat seal strength is lowered as compared with the case where the Ziegler PP is used.

  In addition, the polypropylene film containing low-density polyethylene and amorphous ethylene-α-olefin copolymer has insufficient mechanical strength such as tensile strength and tensile rupture stress, or has low fusing seal strength. When using a fusing seal product with a fusing seal, the film or film seal may be damaged during automatic packaging or mounting as a label, and the tensile strength, tensile breaking stress and Improvement of the fusing seal strength is desired.

However, various proposals have been made as a biaxially stretched polypropylene film (OPP film) for fusing seal with improved fusing seal strength (see, for example, Patent Documents 1 to 4).
For example, Patent Document 1 includes an intermediate layer formed of a propylene homopolymer, and a skin layer formed of a propylene random copolymer provided on the front and back surfaces so as to sandwich the intermediate layer. In addition, an OPP film for fusing sealing is disclosed, wherein the intermediate layer contains 0.005 to 0.1 parts by weight of a crystallization nucleating agent with respect to 100 parts by mass of a propylene homopolymer. .
Patent Document 2 discloses a laminated film including at least two layers of a mat layer and a seal layer, wherein the mat layer has a propylene-based block copolymer (A) as a main component and at least an alkyl sulfonate. The antistatic agent contained is added to 3000 to 10000 ppm, and the seal layer is 50 to 80% by weight of the propylene random copolymer resin (B), and ethylene having a density of 0.870 to 0.895. A total of 2000 to 5000 ppm of a lubricant and / or an antistatic agent is added to 100 parts by weight of a resin composition comprising 20 to 50% by weight of an α-olefin copolymer resin (C). A polyolefin resin laminated film is disclosed.
In Patent Document 3, a sealing layer mainly composed of a polyolefin resin is laminated on both the front and back surfaces of a base layer mainly composed of a polypropylene resin, is biaxially stretched, and has a thickness of 10 μm or more and less than 70 μm. And a polypropylene resin laminated film for packaging fresh products having a haze value of 0.4% or more and 5.0% or less, and a polypropylene resin constituting a base layer and a seal layer is formed by a gas phase method. And satisfying that at least one of inorganic particles is added to the seal layer and an antifogging agent is blended in at least one of the resin forming the base layer and the resin forming the seal layer. A polypropylene resin laminated film for packaging fresh products is disclosed.
Furthermore, in the above-mentioned Patent Document 4, there are two layers of an (A) layer containing a propylene homopolymer having an NMR pentad fraction of 93 to 98% and a (B) layer containing a propylene random copolymer and a polyethylene resin. A biaxially oriented polypropylene-based film characterized by having it is disclosed.
However, the proposed OPP film for fusing seal is still not sufficient in terms of performance such as fusing seal strength.

On the other hand, Patent Document 5 discloses a propylene homopolymer having a branch number of 0.1 / 1000 skeleton carbon or more.
Polypropylene stretched films, especially polypropylene biaxially stretched films, are widely used mainly for food packaging applications such as packaging materials due to their excellent mechanical properties and optical properties. Since a resin polymerized with a Natta (ZN) -based catalyst is mainly used, it is inferior in cleanliness. Therefore, a clean material with less stickiness, bleedout, residual volatile matter, etc. is required.

JP 2013-27977 A JP 2011-121262 A JP 2009-51134 A JP 2007-253349 A JP 2007-154121 A

  An object of the present invention is to provide a polypropylene-based resin composition for a sealant and a polypropylene-based film that are excellent in fusing sealing properties and cleanliness (stickiness, bleed out, low elution components, etc.) in view of the current state of the prior art. .

  As a result of intensive research to solve the above-mentioned problems, the present inventors have found that a propylene resin polymerized using a metallocene catalyst and a polypropylene having a specific long-chain branched structure as a resin composition for sealants. When the resin and the resin were combined at a specific ratio, it was found that the fusing seal strength was greatly improved while maintaining the cleanness of the propylene-based resin polymerized using the metallocene catalyst, and the present invention was completed. .

That is, according to the first invention of the present invention, the polypropylene resin (X) having the following properties (X-i) to (X-iii) and having a long-chain branched structure, 3 to 50% by weight, and Polypropylene resin composition for sealant, characterized in that it contains 50 to 97% by weight of a propylene resin (Y) polymerized using a metallocene catalyst and made of a propylene homopolymer or a propylene-α-olefin copolymer Things are provided.
(Xi): Melt flow rate (MFR: 230 ° C., 2.16 kg load) is 1.0 to 80.0 g / 10 min.
(X-ii): The melting peak temperature (Tm) measured by DSC method (differential scanning calorimeter measurement) is 110 ° C to 150 ° C.
(X-iii): The degree of strain hardening (λmax) in the measurement of elongational viscosity is 1.5 to 6.0.

In addition, according to the second invention, there is provided a polypropylene resin composition for a sealant characterized in that, in the first invention, the polypropylene resin (X) has the following property (X-iv).
(X-iv): The ratio (Q value) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is 2.5 to 5.5.
Furthermore, according to the third invention, in the first or second invention, the polypropylene resin (X) has the following properties (Xv) to (X-vi): A resin composition is provided.
(Xv): The ratio (CXS) of the component that is soluble in p-xylene at 25 ° C. is 0.01 to 5.0% by weight.
(X-vi): The mm fraction of three propylene units linked by ¹³ C-NMR is 95% or more.

  According to a fourth invention, there is provided a polypropylene resin for sealant characterized in that in any one of the first to third inventions, the propylene resin (Y) is a propylene-α-olefin copolymer. The

  According to a fifth invention, in any one of the first to fourth inventions, the propylene resin (Y) is a propylene-α-olefin copolymer having an MFR of 1 to 10 g / 10 min. A polypropylene resin composition for sealant is provided.

  According to a sixth invention, in any one of the first to fifth inventions, the propylene resin (Y) is a propylene-α-olefin copolymer having a melting point of 110 to 150 ° C. A polypropylene resin composition for sealants is provided.

According to the seventh invention, the polypropylene resin composition for sealant according to any one of the first to sixth inventions is laminated by coextrusion through an intermediate layer and is stretched at least in a uniaxial direction. A polypropylene-based film is provided.
According to the eighth invention, in the seventh invention, there is provided a polypropylene film characterized by being used for a fusing seal.

  According to the ninth invention, there is provided a fusing seal bag, which is formed by fusing a polypropylene film according to the seventh or eighth invention.

  The polypropylene resin composition for sealant of the present invention is excellent in fusing seal characteristics and cleanliness (stickiness, bleed out, low elution components, etc.). And the polypropylene film obtained and the fusing seal bag using the same are excellent in sealing strength even in high-speed fusing sealing.

It is an example of the plot figure of uniaxial elongation viscosity. It is an example of catalyst component [A-1] origin, catalyst component [A-2] origin, and the whole molecular weight distribution. About polymerization examples 1-5, the relationship between the hydrogen supply amount (Nml), the ethylene supply amount (g), and the strain hardening degree of the obtained polymer is illustrated.

  Embodiments of the present invention will be described in detail below. However, the description of the constituent elements described below is an example of the embodiments of the present invention. The description is not limited.

  The polypropylene resin composition for sealant of the present invention (hereinafter sometimes referred to as a resin composition) is a polypropylene resin component having a long-chain branched structure, particularly a polypropylene resin component (X) 3 having a specific physical property. 50% by weight and 50 to 97% by weight of a propylene-based resin (Y) made of a propylene homopolymer or a propylene-α-olefin copolymer, polymerized using a metallocene catalyst.

The range of the amount of the polypropylene resin component (X) relative to the total amount of the resin composition is 3 to 50% by weight, preferably 5 to 50% by weight, and more preferably 10 to 40% by weight. Correspondingly, the range of the amount of the propylene-based resin (Y) is 50 to 97% by weight, preferably 50 to 95% by weight, and more preferably 60 to 90% by weight. For those outside this range, for example, when the polypropylene resin component (X) having a long-chain branched structure is too small, the fusing seal characteristics are not expressed, and conversely, when it is too large, the problem of poor appearance, The problem of reduced productivity arises.
In the following, characteristics to be satisfied by the components (X) and (Y) will be described in detail for each item.

I. Polypropylene resin component (X) having a long-chain branched structure
In the polypropylene resin composition for sealant of the present invention, first, it is essential to have the following properties (X-i) to (X-iii), and a polypropylene resin having a long-chain branched structure ( X) is used.
(X-i): MFR is 1.0 to 80.0 g / 10 min.
(X-ii): Melting peak temperature (Tm) measured by DSC method (differential scanning calorimeter measurement) is 110-150 degreeC.
(X-iii): The degree of strain hardening (λmax) in the measurement of elongational viscosity is 1.5 to 6.0.

1. (X-i): MFR
The melt flow rate (MFR) of the polypropylene resin (X) having a long-chain branched structure in the present invention needs to be in the range of 1.0 to 80.0 g / 10 minutes, preferably 2.0 to 20 0.0 g / 10 min, more preferably 3.0 to 10.0 g / 10 min. If it falls below this range, the fluidity will be insufficient, causing problems such as too high load on the extruder for various moldings. On the other hand, if it exceeds this range, the properties as a high melt tension material will be poor due to insufficient tension. Become unsuitable.
The method for controlling the MFR value is well known, and can be easily adjusted by adjusting the temperature and pressure, which are polymerization conditions of the polypropylene resin (X), or by controlling the amount of hydrogen added during polymerization of a chain transfer agent such as hydrogen. Adjustments can be made.
MFR is JIS K7210: 1999 “Method of plastic-thermoplastic melt mass flow rate (MFR) and test method for melt volume flow rate (MVR)”, condition M (230 ° C., 2.16 kg load). Measured according to the standard, the unit is g / 10 minutes.

2. (X-ii): Melting peak temperature (Tm)
The melting peak temperature (Tm) measured by the DSC method (differential scanning calorimetry measurement) of the polypropylene resin (X) having a long chain branched structure in the present invention needs to be in the range of 110 ° C to 150 ° C, Preferably they are 110 to 145 degreeC, More preferably, it is 115 to 140 degreeC, More preferably, it is 120 to 135 degreeC. When the temperature is lower than 110 ° C., the heat resistance of the film is lowered, which is not preferable. When the temperature is higher than 150 ° C., the transparency of the film is deteriorated and the appearance is deteriorated.
As for the melting point, DSC (Q2000 type) manufactured by TA Co., Ltd. was used, a sample of 5.0 mg was taken, heated to 200 ° C. and held for 5 minutes, and then the temperature was lowered to 40 ° C. at a rate of 10 ° C./min. The temperature at the top of the endothermic peak was measured again at a temperature elevation rate of 10 ° C./min.

3. (X-iii): Strain hardening degree (λmax) in measurement of elongational viscosity
The polypropylene resin (X) having a long-chain branched structure in the present invention needs to have a strain hardening degree (λmax) in the range of 1.5 to 6.0 in the measurement of uniaxial elongational viscosity.
If λmax is too small, the melt tension decreases. Accordingly, λmax is preferably 1.5 or more, more preferably 3.0 or more, and further preferably 4.0 or more. On the other hand, if λmax is too large, dispersibility with other resins is poor. Moreover, the problem that transparency of a film will deteriorate arises. Accordingly, λmax is preferably 6.0 or less, more preferably 5.9 or less, and even more preferably 5.8 or less.

  λmax can be determined by measuring uniaxial elongational viscosity with a measuring instrument and a measuring method as described in Polymer 42 (2001) 8663, for example. The value of λmax is in principle the same value by any method as long as it is a measurement of uniaxial elongational viscosity. In the present invention, the measuring instrument and measuring method of λmax are as follows.

・ Device: Ales manufactured by Rheometrics
-Jig: EXTENSIONAL VISUALITY FIXTURE, manufactured by TA Instruments
・ Measurement temperature: 180 ℃
-Strain rate: 0.1 / sec
-Preparation of test piece: A sheet having a size of 18 mm x 10 mm and a thickness of 0.7 mm is formed by press molding.

  Prior to the preparation of the test piece, the sample is once dissolved in hot xylene, the solution is put into a large amount of ethanol, the re-precipitated material is filtered, and the sample is homogenized. When the polymer powder is directly pressed and used as a test piece, the measured values vary. As the cause, for example, when the propylene-based polymer is a long-chain branched type, in the measurement method for measuring the response when a strain such as uniaxial extensional viscosity is applied, the branched chain and the main chain are aligned in the same direction. This is thought to be due to a phenomenon called share modification.

In the case of strain rate: 0.1 / sec, the uniaxial elongation viscosity is plotted on a logarithmic graph with time (t) on the horizontal axis and uniaxial elongation viscosity η _E (Pa · sec) on the vertical axis. On the log-log graph, the relationship between the time until strain hardening occurs and the uniaxial extensional viscosity is approximated by a straight line. In the present invention, linear approximation is performed in the range of 0.05 to 0.5 (time 0.5 to 5 seconds). The maximum value (ηmax) of the uniaxial elongation viscosity η _E until the strain amount becomes 4.0 (time 40 seconds), the time, and the value of the uniaxial elongation viscosity (ηlin) on the approximate line at that time are determined. Let ηmax / ηlin be λmax. FIG. 1 is an example of a plot of uniaxial extensional viscosity.
The strain rate can be measured in the range of 0.001 / sec to 10.0 / sec, and the strain hardening degree varies depending on the difference in strain rate. The strain rate dependency of the strain hardening degree is considered to change depending on the shape and length of the introduced branch.
In addition, when the value of (eta) max / (eta) lin = (lambda) max until said distortion reaches 4.0 is defined as having strain hardening property.
Strain hardenability develops strain hardenability when a long-term relaxation component into which a branched component is introduced exists. Therefore, the value of λmax is larger as the amount of branching components and the branching length are larger.

  λmax can be adjusted by controlling the amount of the branched chain and the length of the branched chain in the long-chain branched propylene polymer. For example, the molecular weight of the macromer in the macromer synthesis process will correlate with the length of the branched chain, and the ratio of propylene and macromer in the macromer copolymerization process will correlate with the amount of branched chain. Will do. When a catalyst containing two types of metallocene complexes is used, it contributes to the synthesis of the macromer by combining the metallocene complex mainly contributing to the synthesis of the macromer and the metallocene complex mainly contributing to the copolymerization of propylene and the macromer. Depending on the selection of the metallocene complex, the molecular weight of the macromer may be adjusted, and by selecting the activity of the metallocene complex that contributes to the synthesis of the macromer and the activity of the metallocene complex that mainly contributes to the copolymerization of propylene and the macromer, The amount of macromer uptake could be adjusted, and the amount of macromer uptake could be selected by selecting the amount of metallocene complex used to contribute to the synthesis of the macromer and the amount of metallocene complex used mainly for the copolymerization of propylene and macromer. You can adjust the size of.

In general, for the development of strain hardening, the length of the branched chain is required to be 7,000 or more, which is an entanglement molecular weight of polypropylene (reference: Macromolecules. 1998, 31, 1335, Macromolecules. 2002). 35, 10062).
This corresponds to about 400 or more in terms of the number of skeleton carbon atoms. As used herein, the skeleton carbon means all carbon atoms other than methyl carbon when propylene is used alone or when copolymerization of propylene and ethylene is performed. When butene is used in addition to the above monomer, it means all carbon atoms other than methyl carbon and ethyl carbon atoms. It is believed that the melt tension becomes higher as the length of the branched chain becomes longer. Further, it is considered that when the length of the branched chain becomes longer, strain hardening is detected even in a slower strain rate region in the measurement of the extensional viscosity.

Therefore, the length of the branched chain of the polypropylene resin (X) of the present invention is preferably 500 (polypropylene molecular weight conversion: 11,000) or more, more preferably 1000 (polypropylene molecular weight conversion: 2.1) as the skeleton carbon number. 10,000) or more, more preferably 2000 (polypropylene molecular weight conversion: 42,000) or more.
The polypropylene molecular weight converted value here is strictly different from the molecular weight value measured by GPC, but approximates the number average molecular weight (Mn) measured by GPC. Therefore, the length of the branched chain of the polypropylene resin (X) of the present invention is preferably 11,000 or more, more preferably 21,000 or more, and still more preferably as the number average molecular weight (Mn) measured by GPC. Is over 42,000.

4). (X-iv): GPC (Q value)
The polypropylene resin (X) having a long-chain branched structure in the present invention is a ratio of the weight average molecular weight (Mw) and the number average molecular weight (Mn) obtained by gel permeation chromatography (GPC) [Mw / Mn (hereinafter Q Value))] is preferably 2.5 to 5.5.
The Q value is an index representing the spread of the molecular weight distribution, and the larger the value, the wider the molecular weight distribution. Therefore, from the viewpoint of moldability, the Q value is preferably 2.5 or more, more preferably 2.6 or more, and further preferably 2.7 or more. On the other hand, from the viewpoint of cleanliness due to the amount of the low molecular weight component, the Q value is preferably 5.5 or less, more preferably 5.2 or less, and even more preferably less than 5.0.

The Q value is a physical property value affected by the uniformity of the active site of the catalyst. Since a catalyst containing a single metallocene complex has a relatively uniform active site, a catalyst containing a single metallocene complex is used. In many cases, the resulting propylene polymer has a Q value of about 2 to 2.5.
Therefore, the molecular weight distribution as in the present invention is such that when a propylene polymer is polymerized in one polymerization stage by a multistage polymerization method and a propylene polymer having a different molecular weight is produced in another polymerization stage, the polymerization stage is different in each polymerization stage. Combinations of metallocene complexes that give propylene polymers with different molecular weights by increasing or decreasing the molecular weight of the propylene polymer to be produced, increasing or decreasing the weight ratio of the polymerization amount, and methods using a catalyst containing multiple metallocene complexes And by adjusting the ratio, it is possible to provide a distribution of the quality of active sites, to use a catalyst in which a metallocene complex is supported on a support so that the distribution of the quality of active sites is generated, It can be obtained by using a method or the like.
Further, the Q value can be easily adjusted by adding a chain transfer agent such as hydrogen during the polymerization. Furthermore, it can be adjusted by the comonomer content by utilizing the tendency that the Q value becomes narrower when the comonomer content such as ethylene is increased.

A specific GPC measurement method is as follows.
Apparatus: GPC manufactured by Waters (ALC / GPC 150C)
Detector: MIRAN 1A IR detector manufactured by FOXBORO (measurement wavelength: 3.42 μm)
Column: Showa Denko AD806M / S (3 in series)
-Mobile phase solvent: orthodichlorobenzene (ODCB)
・ Measurement temperature: 140 ℃
・ Flow rate: 1.0 ml / min
・ Injection volume: 0.2ml
Sample preparation: Prepare a 1 mg / mL solution using ODCB (containing 0.5 mg / mL BHT) and dissolve it at 140 ° C. for about 1 hour.
Conversion from the retention capacity obtained by GPC measurement to the molecular weight is performed using a calibration curve prepared in advance by standard polystyrene (PS). The standard polystyrenes used are all the following brands manufactured by Tosoh Corporation.
F380, F288, F128, F80, F40, F20, F10, F4, F1, A5000, A2500, A1000
A calibration curve is created by injecting 0.2 mL of a solution dissolved in ODCB (containing 0.5 mg / mL BHT) so that each is 0.5 mg / mL. The calibration curve uses a cubic equation obtained by approximation by the least square method.
In addition, the following numerical value is 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

5. (Xv): 25 ° C. paraxylene soluble component amount (CXS)
The polypropylene resin (X) having a long-chain branched structure used in the present invention has high stereoregularity and preferably has few low crystallinity components that cause stickiness and bleed-out when it becomes a product. This low crystalline component is evaluated by the amount of xylene soluble component (CXS) at 25 ° C., and it is preferably 0.01 to 5.0% by weight based on the total amount of component (X). About an upper limit, More preferably, it is 3.0 weight%, More preferably, it is 1.0 weight%, Most preferably, it is 0.5 weight%. A more preferred lower limit is 0.03% by weight.

The details of the CXS measurement method are as follows.
A 2 g sample is dissolved in 300 ml of p-xylene (containing 0.5 mg / ml BHT) at 130 ° C. to make a solution, and then left at 25 ° C. for 12 hours. Thereafter, the precipitated polymer is filtered off, p-xylene is evaporated from the filtrate, and further dried under reduced pressure at 100 ° C. for 12 hours to recover room temperature xylene soluble components. The ratio (% by weight) of the weight of the recovered component to the charged sample weight is defined as CXS.

For CXS, it is preferable to select a bridged indene complex or an azulene complex so that the stereoregularity is relatively high, and in particular, control by adjusting the bulkiness of the 2- or 4-position substituent. Is possible. When two complexes are combined, the total amount of CXS can be controlled by selecting a highly stereoregular complex and adjusting the complex ratio.
Further, when the amount of the organoaluminum compound is increased, the stereoregularity is deteriorated by coordinating or altering a part of the complex. Therefore, the amount of CXS can be controlled by optimizing the amount of organoaluminum compound.

6). (X-vi): mm fraction of propylene unit 3 chain by ¹³ C-NMR The polypropylene resin (X) having a long chain branched structure used in the present invention is the mm fraction of propylene unit 3 chain obtained by ¹³ C-NMR. The rate is preferably 95% or more.
The mm fraction is the ratio of three propylene unit chains in which the direction of methyl branching in each propylene unit is the same among arbitrary three propylene unit chains composed of head-to-tail bonds in the polymer chain. The mm fraction is a value indicating the degree to which the steric structure of the methyl group in the polypropylene molecular chain is isotactically controlled, and the higher the value, the higher the isospecificity.
From the viewpoint of mechanical properties such as elastic modulus, the mm fraction is preferably 95% or more, more preferably 96% or more, and still more preferably 97% or more.
Further, the stereoregularity of the main chain and the branched chain is determined by the stereoregular ability of the catalyst components [A-1] and [A-2] used in the method for producing a propylene polymer described later. When the isospecificity of the branched chain is low, even if the isospecificity of the main chain is high, the crystallinity of the polymer as a whole is lowered, and mechanical properties such as elastic modulus are lowered. Therefore, the polypropylene resin (X) of the present invention preferably has high isospecificity in both the main chain and the branched chain. The value is preferably 95% or more, more preferably 96% or more, and still more preferably 97% or more in terms of mm fraction for both the main chain and the side chain.
The mm fraction can be easily adjusted by selecting the metallocene complex to be used, the polymerization temperature, and the like.

In addition, the detail of the measuring method of mm fraction of the propylene unit 3 chain | strand by ¹³ C-NMR is as follows.
A sample of 375 mg is completely dissolved in 2.5 ml of deuterated 1,1,2,2, -tetrachloroethane in an NMR sample tube (10φ), and then measured at 125 ° C. by a proton complete decoupling method. The chemical shift sets the central peak of the three peaks of deuterated 1,1,2,2-tetrachloroethane to 74.2 ppm. The chemical shift of other carbon peaks is based on this.
Flip angle: 90 degrees Pulse interval: 10 seconds Resonance frequency: 100 MHz or more Integration frequency: 10,000 times or more Observation range: -20 ppm to 179 ppm
Number of data points: 32768
The analysis of the mm fraction is performed using a ¹³ C-NMR spectrum measured under the above conditions.
The spectrum is assigned with reference to Macromolecules, (1975) 8 pp. 687 and Polymer, 30 pages 1350 (1989).
Note that a more specific method for determining the mm fraction is described in detail in paragraphs [0053] to [0065] of Japanese Patent Laid-Open No. 2009-275207, and the present invention is performed according to this method. .

II. Method for Producing Polypropylene Resin (X) The mechanism and mechanism for developing the branched structure of the polypropylene resin (X) having a long-chain branched structure of the present invention are inferred as follows, and the catalyst component and propylene heavy polymer as described later are used. The preferable aspect of the polymerization method of a coalescence is shown.

Inference mechanism of polymerization With regard to the branched structure, the present inventors have inferred as follows in consideration of the mechanism and mechanism capable of forming a branched structure.
That is, from an active species that causes a special chain transfer reaction generally called β-methyl elimination, one end of the polymer mainly exhibits a propenyl structure (vinyl structure), and a so-called macromer is formed.
The terminal propenyl structure (vinyl structure) terminated by the β-methyl elimination reaction is shown below (reference document: Macromol. Rapid Commun. 2000, 21, 1103-1107).

It is speculated that this macromer and propylene are capable of generating higher molecular weights and are taken into active species having better copolymerizability, and the copolymerization of the macromer and propylene proceeds.
Therefore, the polypropylene resin (X) of the present invention has a specific branched structure as shown in the following structural formula (2).
In Structural Formula (2), Ca, Cb, and Cc represent methylene carbon adjacent to the branched carbon, Cbr represents the methine carbon at the root of the branched chain, and P ¹ , P ² , and P ³ represent propylene-based heavy ions. Combined residues are indicated.
P ¹ , P ² , and P ³ may contain a branched carbon (Cbr) different from Cbr described in the structural formula (2) in itself.

Such a branched structure is identified by ¹³ C-NMR analysis. The assignment of each peak is described in Macromolecules, Vol. 35, no. 10. The description of 2002, pages 3839-3842 can be referred to. That is, a total of three methylene carbons (Ca, Cb, Cc) were observed, each at 43.9-44.1 ppm, 44.5-44.7 ppm, and 44.7-44.9 ppm. Methine carbon (Cbr) is observed at ˜31.7 ppm. Hereinafter, the methine carbon observed at 31.5 to 31.7 ppm may be abbreviated as branched carbon (Cbr).
It is characterized in that three methylene carbons adjacent to the branched methine carbon Cbr are observed in three non-equivalent diastereotopics.

The branched chain assigned by ¹³ C-NMR referred to in the present invention represents a propylene polymer residue having 5 or more carbon atoms branched from the main chain of the propylene polymer. It can be distinguished from a branch having 4 or less carbon atoms by the difference in the peak position of the branched carbon (see Macromol. Chem. Phys. 2003, Vol. 204, p. 1738).

In general, considering the regulation of the number and length of branches of a polymer, the greater the number of branches, the higher the melt tension. On the other hand, it is considered that if the number of branches is unevenly distributed between the molecules, gel is generated and the effect of improving the melt tension is reduced.
The number of branches is defined as the number of branches (density) per 1000 total skeleton-forming carbons of the branched carbon (Cbr) observed at 31.5 to 31.7 ppm using the assignment by ¹³ C-NMR. . However, the total skeleton-forming carbon means all carbon atoms other than methyl carbon.

The polypropylene resin (X) showing the improved melt tension of the present invention has a trace amount of branched components as a result of ¹³ C-NMR measurement, and the amount thereof is about 0.1 or less. On the other hand, when the amount of branching is too large, there is a concern that gel is generated and the appearance of the molded product is impaired. Furthermore, there is a problem that when the film is stretched at a high speed at the time of molding, so-called melt ductility is deteriorated, that is, the melt breaks.
Therefore, the number of branches is preferably 0.1 or less, more preferably 0.08 or less, and still more preferably 0.06 or less. The lower limit is 0.01 or more.
By setting the number of branches per 1000 skeleton-forming carbons to 0.1 or less, λmax can be made less than 6.

Further, when considering the polymerization mechanism, since the macromer is incorporated into the main chain to form a branched structure, the average molecular weight of the macromer is characterized as the average molecular weight of the incorporated branched chain.
For example, in the polypropylene resin (X) of the present invention, when the molecular weight of the macromer is 50,000 in terms of the number average molecular weight, the average molecular weight of the incorporated branched chain is 50,000, which is interpreted as 2400 in terms of skeleton carbon. The
The number average molecular weight of the macromer can be determined from the molecular weight when the polymerization of the macromer alone is carried out using only the active species producing the macromer or the peak top of the macromer portion in the propylene polymer in GPC.

  On the other hand, the branched distribution of the polymer can be measured by GPC-vis or GPC-malls, but considering the polymerization mechanism, the macromer is incorporated into the active species having a higher molecular weight and higher copolymerization, Since it is considered that branching is generated, it is considered that long chain branching is introduced into the high molecular weight component.

The molecular weight component derived from the catalyst component [A-2], which will be described later, has a higher molecular weight than the molecular weight component derived from the catalyst component [A-1]. ] Is also considered to have a distribution form in which branching is introduced.
The molecular weight component derived from the catalyst component [A-1] also has a branched structure formed by incorporating the macromer with the catalyst component [A-1] itself.
An example of the molecular weight distribution derived from the catalyst component [A-1] and the catalyst component [A-2] is shown in FIG.

Describing the relationship between the number of branches and the branch distribution, in order to improve the melt tension, it is generally considered that a large number of branches is necessary, and in Patent Document 5 (Japanese Patent Laid-Open No. 2007-154121), A propylene homopolymer having a branch number of 0.1 / 1000 skeleton carbon or more is disclosed.
However, since the propylene homopolymer disclosed here is produced by a single complex, the molecular weight distribution of the propylene polymer is different, and branching components are not effectively introduced into the high molecular weight side in the molecular weight distribution. Therefore, although the degree of strain hardening is small, a large number of branches are included. In addition, the molecular weight distribution is largely biased toward the high molecular weight side. As a result, there arises a problem that the extensibility at the time of melting is considered to be caused by the number of branch points.
Moreover, although regularity is low, when used as a heat seal material with a high melting point, the heat seal temperature cannot be sufficiently lowered during molding. Moreover, since the regularity itself is low, the sticky component increases to the low molecular weight component.
The polypropylene resin (X) of the present invention does not necessarily have a larger number of branches than the conventional branched polymer, but it can be melted by introducing a branch to the high molecular weight side by combining a plurality of complexes. By improving the tension and controlling the amount of branching, deterioration of the spreadability at the time of melting is suppressed.

Such branching degree distribution can be confirmed by performing measurement such as GPC-Vis.
Here, regarding the GPC-Vis measurement method, as long as the method is the same in principle, the distribution information regarding the branch can be obtained by any method. For example, regarding the preferable measurement method and measurement instrument, The method described in the structural analysis example described later can be given.

The stereoregularity of the side chain will be described. The stereoregularity of the main chain and the side chain is determined by the stereoregular ability of the catalyst components [A-1] and [A-2] used. If the stereoregularity of the side chain is low, even if the crystallinity of the main chain is high, the overall crystallinity is degraded. Therefore, in order to obtain a higher-rigidity polymer, it is preferable that the side chain and the main chain have high stereoregularity. As the value, both the main chain and the side chain are 95% or more in mm fraction. Especially preferably, it is 96% or more, More preferably, it is 97% or more.
The stereoregularity of the side chain is considered to be equal to the stereoregularity of the polymer due to the catalyst component [A-1] alone.
The details of the stereoregularity of the main chain and side chain will be described later.

As described above, the polypropylene resin (X) of the present invention is a long chain branched type in which melt spreadability and melt tension are controlled and excellent in balance between physical properties and workability. In contrast to the conventional propylene-based polymer, for example, as described above, Patent Document 5 (Japanese Patent Laid-Open No. 2007-154121) discloses a propylene homopolymer having a branch number of 0.1 / 1000 skeleton carbon or more. However, since the propylene homopolymer disclosed here is produced with a single complex, the molecular weight distribution of the propylene polymer is different, and branching components are effectively introduced into the high molecular weight side during the molecular weight distribution. However, the degree of strain hardening is small, but the number of branches is large, and the molecular weight distribution is largely biased toward the high molecular weight, resulting in deterioration of the spreadability at the time of melting, which is considered to be derived from the number of branch points. Even if compared with the polypropylene resin (X) of the present invention, the effect of improving the melt tension is not sufficient. In addition, in the commercial product of polypropylene that is crosslinked by electron beam irradiation and has a high degree of long-chain branching (base melt high melt tension polypropylene, “PF814”), the branched carbon of the structural formula (2) described above is not detected. The isotactic triad fraction (mm fraction) by ¹³ C-NMR is low (92.5%), and it is considered that molecular cleavage and isomerization occur simultaneously with crosslinking during irradiation with an electron beam, An increase in low molecular weight components, resulting in an increase in solvent soluble components. In addition, as another general method for controlling the molding processing characteristics, control is performed by expanding the molecular weight distribution. However, when the molecular weight distribution is expanded, the low molecular weight component is increased, resulting in molding. Demerits such as deterioration of the surface characteristics of the body, deterioration of mechanical properties and heat sealability occur.
However, the polypropylene resin (X) of the present invention is controlled by expanding the molecular weight distribution by broadening the molecular weight distribution and introducing branches. However, the low molecular weight component does not increase and the high molecular weight component does not increase. Since it increases, the above disadvantages do not occur.
As described above, since the polypropylene resin (X) of the present invention is a long-chain branched type, the balance between physical properties and processability is controlled by controlling the melt ductility and melt tension not found in conventional propylene polymers. It is excellent.

2. Monomer, Comonomer The polypropylene resin (X) of the present invention is a polymer obtained by copolymerizing propylene and a comonomer. As the comonomer, one or two or more kinds of comonomers selected from ethylene, 1-butene, 1-pentene, 1-hexene, 1-octene and the like can be used, and ethylene is preferable. As a comonomer, 1.0 mol% or more and 10.0 mol% or less may be contained.
Propylene-based random copolymer obtained by copolymerizing propylene and a small amount of comonomer is used in fields such as containers and lids because the comonomer lowers crystallinity compared to propylene homopolymer. In some cases, there is an advantage that flexibility and transparency are improved.
Therefore, a random copolymer containing a comonomer is preferable.
As a role of the comonomer added at the time of polymerization, the chain transfer to the comonomer competes with the β methyl elimination reaction to reduce the production efficiency of the macromer. As a result, the amount of comonomer can be controlled, and the physical property values such as λmax of the polypropylene resin (X) of the present invention can be controlled within an appropriate range.
In addition, regarding the range of the amount of comonomer, if there is too much comonomer, the crystallinity is lowered too much, the melting point is lowered, and the heat resistance of the product is deteriorated.
Therefore, in order to obtain the polypropylene resin (X) of the present invention having a good balance of flexibility, transparency, heat resistance, and melt tension, it is preferable that the content of comonomer such as ethylene is 10 mol% or less. Preferably it is 9.0 mol% or less, More preferably, it is 8.0 mol% or less.
On the other hand, if the amount of comonomer is too small, the crystallinity becomes too high, and when used as a heat seal material, the heat seal temperature must be increased, impairing the performance of the product. Moreover, when crystallinity becomes high, transparency will deteriorate. In addition, when blended with other materials, if there is a difference in crystallinity from each other, the dispersion becomes poor, and defects in appearance such as unevenness appear on the film.
Therefore, in order to obtain the polypropylene resin (X) of the present invention, the content of comonomer such as ethylene is preferably 1.0 mol% or more, more preferably 2.0 mol% or more, and still more preferably It is 3.0 mol% or more.

[Measurement of ethylene content by ¹³ C-NMR]
The ethylene content of the polypropylene resin (X) of the present invention is determined by analyzing a measured ¹³ C-NMR spectrum according to the following conditions by a proton complete decoupling method.

・ Model: GSX-400 (carbon nuclear resonance frequency 400 MHz) manufactured by JEOL Ltd.
Solvent: ODCB / heavy benzene = 4/1 (volume ratio)
Concentration: 100 mg / mL
・ Temperature: 130 ℃
・ Pulse angle: 90 °
・ Pulse interval: 15 seconds ・ Number of integrations: More than 5,000 times

For example, spectrum assignment may be performed with reference to the following documents.
Macromolecules; 17, 1950 (1984).
The attribution of spectra measured under the above conditions is as shown in the table below. Symbols such as Sαα in the table are in accordance with the notation of the following document, P represents methyl carbon, S represents methylene carbon, and T represents methine carbon.
Carman, Macromolecules; 10,536 (1977)

Hereinafter, when “P” is a propylene unit in a copolymer chain and “E” is an ethylene unit, six types of triads of PPP, PPE, EPE, PEP, PEE, and EEE may exist in the chain. . As described in Macromolecules, 15 1150 (1982), the concentration of these triads and the peak intensity of the spectrum are linked by the following relational expressions <1> to <6>.
[PPP] = k × I (Tββ) <1>
[PPE] = k × I (Tβδ) <2>
[EPE] = k × I (Tδδ) <3>
[PEP] = k × I (Sββ) <4>
[PEE] = k × I (Sβδ) <5>
[EEE] = k × [I (Sδδ) / 2 + I (Sγδ) / 4} <6>
Here, [] indicates the fraction of triads, for example, [PPP] is the fraction of PPP triads in all triads.
Therefore,
[PPP] + [PPE] + [EPE] + [PEP] + [PEE] + [EEE] = 1 <7>
Further, k is a constant, I indicates the spectral intensity, and for example, I (Tββ) means the intensity of the peak at 28.7 ppm attributed to Tββ.

By using the above relational expressions <1> to <7>, the fraction of each triad is obtained, and the ethylene content is obtained from the following expression.
Ethylene content (mol%) = ([PEP] + [PEE] + [EEE]) × 100

  The propylene random copolymer according to the present invention contains a small amount of propylene regioregular defects (2,1-bonds and / or 1,3-bonds), thereby producing the following minute peaks. .

In order to obtain an accurate ethylene content, it is necessary to include the peaks derived from these regioregular defects in the calculation, but it is difficult to completely separate and identify the peaks derived from regioregular defects. In addition, since the amount of heterogeneous bonds is small, the ethylene content in the present invention is the same as in the analysis of the copolymer produced with a Ziegler-Natta catalyst substantially free of regioregular defects, as described in <1> to It is determined using the relational expression <7>.
Conversion from mol% (X) of ethylene content to wt% is performed using the following formula.
Ethylene content (% by weight) = (28 × X / 100) / {28 × X / 100 + 42 × (1−X / 100)} × 100

3. Catalyst The method for producing the polypropylene resin (X) of the present invention is not particularly limited as long as it is a method by which a propylene-based polymer satisfying the above physical properties that are the characteristics of the present invention is obtained. Examples thereof include a method using a plurality of complexes as described below from which a chain branched propylene polymer is obtained.
That is, a method for producing the above-mentioned long-chain branched propylene polymer, wherein the following catalyst components (A), (B) and (C) are used as propylene polymerization catalysts, and propylene and α- Copolymerization of olefins and polymerization methods include bulk polymerization using propylene as a solvent or gas phase polymerization for maintaining each monomer in the gaseous state, and a method for producing a propylene polymer having the characteristics of the present invention. It is done.
(A): at least one from component [A-1] which is a compound represented by the following general formula (a1) and at least one from component [A-2] which is a compound represented by general formula (a2) Type, selected two or more Group 4 transition metal compounds Component [A-1]: Compound represented by general formula (a1) Component [A-2]: Compound represented by general formula (a2) (B): Ion exchange layered silicate (C): Organoaluminum compound

Hereinafter, the catalyst components (A), (B), and (C) will be described in detail.
(1) Catalyst component (A)
(I) Component [A-1]: Compound represented by general formula (a1)

[In General Formula (a1), R ¹¹ and R ¹² each independently represent a heterocyclic group containing nitrogen, oxygen or sulfur having 4 to 16 carbon atoms. R ¹³ and R ¹⁴ each independently contain a halogen atom, silicon, oxygen, sulfur, nitrogen, boron, phosphorus, or a plurality of heteroelements selected from these, having 6 to 16 carbon atoms An aryl group, a heterocyclic group containing 6 to 16 carbon atoms, nitrogen, oxygen or sulfur. X ¹¹ and Y ¹¹ 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 group having 1 to 20 carbon atoms. It 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 has a divalent hydrocarbon group having 1 to 20 carbon atoms, a silylene group that may have a hydrocarbon group having 1 to 20 carbon atoms, or a hydrocarbon group having 1 to 20 carbon atoms. Represents a good germylene group. ]

The heterocyclic group containing nitrogen, oxygen or sulfur having 4 to 16 carbon atoms of R ¹¹ and R ¹² is preferably a 2-furyl group, a substituted 2-furyl group, a substituted 2-thienyl group, a substituted group. 2-furfuryl group, more preferably a substituted 2-furyl group.
Moreover, as a substituted 2-furyl group, a substituted 2-thienyl group, and a substituted 2-furfuryl group, an alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, and a propyl group, Examples thereof include halogen atoms such as fluorine atom and chlorine atom, alkoxy groups having 1 to 6 carbon atoms such as methoxy group and ethoxy group, and trialkylsilyl groups. Of these, a methyl group and a trimethylsilyl group are preferable, and a methyl group is particularly preferable.
Further, R ¹¹ and R ¹² are particularly preferably a 2- (5-methyl) -furyl group. R ¹¹ and R ¹² are preferably the same as each other.
However, when a 2- (5-methyl) -furyl group is used, the branching difference becomes too long, and the strain hardening degree may become too large. As R ¹¹ and R ¹² , 2- (5 When a -methyl) -furyl group is used, the physical property value of the propylene polymer can be controlled in combination with a technique such as increasing the ethylene content or increasing the MFR.

The aryl group having 6 to 16 carbon atoms of R ¹³ and R ¹⁴ , which may contain a halogen atom, silicon, oxygen, sulfur, nitrogen, boron, phosphorus, or a plurality of hetero elements selected from these, includes carbon Within the range of 6 to 16, on the aryl cyclic skeleton, one or more hydrocarbon group having 1 to 6 carbon atoms, silicon-containing hydrocarbon group having 1 to 6 carbon atoms, halogen containing 1 to 6 carbon atoms You may have a hydrocarbon group as a substituent.
At least one of R ¹³ and R ¹⁴ is preferably a phenyl group, a 4-tbutylphenyl group, a 2,3-dimethylphenyl group, a 3,5-ditbutylphenyl group, a 4-phenyl-phenyl group, or a chlorophenyl. Group, a naphthyl group, or a phenanthryl group, and more preferably a phenyl group, a 4-tbutylphenyl group, and a 4-chlorophenyl group. Further, it is preferable that R ¹³ and R ¹⁴ are the same.

In the general formula (a1), X ¹¹ and Y ¹¹ are auxiliary ligands and react with the component (B) to generate an active metallocene having olefin polymerization ability. Therefore, as long as this object is achieved, X ¹ and Y ¹ are not limited to the type of ligand, and are independently a hydrogen atom, a halogen atom, or a 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, a phosphorus-containing hydrocarbon group having 1 to 20 carbon atoms, or a silicon-containing hydrocarbon group having 1 to 20 carbon atoms. Show.

In the general formula (a1), Q ¹¹ is a silylene that may have a divalent hydrocarbon group having 1 to 20 carbon atoms and a hydrocarbon group having 1 to 20 carbon atoms that connects two five-membered rings. Or a germylene group which may have a hydrocarbon group having 1 to 20 carbon atoms. When two hydrocarbon groups are present on the above-mentioned silylene group or germylene group, they may be bonded to each other to form a ring structure.
Specific examples of Q ¹¹ include alkylene groups such as methylene, methylmethylene, dimethylmethylene and 1,2-ethylene; arylalkylene groups such as diphenylmethylene; silylene groups; methylsilylene, dimethylsilylene, diethylsilylene, di Alkylsilylene groups such as (n-propyl) silylene, di (i-propyl) silylene, di (cyclohexyl) silylene, (alkyl) (aryl) silylene groups such as methyl (phenyl) silylene; arylsilylene groups such as diphenylsilylene; Alkyl oligosilylene groups such as tetramethyldisilene; germylene groups; alkylgermylene groups in which silicon in the above-mentioned divalent hydrocarbon groups having 1 to 20 carbon atoms is replaced with germanium; (alkyl) (aryl) Germylene group; arylgermylene Examples include groups. In these, the silylene group which has a C1-C20 hydrocarbon group, or the germylene group which has a C1-C20 hydrocarbon group is preferable, and an alkylsilylene group and an alkylgermylene group are especially preferable.

Of 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, dic B [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′-diphenylsilylenebis {2- (5-methyl-2-furyl) -4- Enyl-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-fluoro Phenyl) -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-tert-butylphenyl) -indenyl}] hafnium, di Loro [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) -indene ]} Hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (2-phenanthryl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylene Bis {2- (5-methyl-2-furyl) -4- (9-phenanthryl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-t-butyl-2-furyl) ) -4- (1-Naphtyl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-tert-butyl-2-furyl) -4- (2-naphthyl) -indenyl} ] Hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-tert-butyl-2-furyl) -4- (2-phenanthryl) -indenyl}] hafnium, dichloro [1, '-Dimethylsilylenebis {2- (5-t-butyl-2-furyl) -4- (9-phenanthryl) -indenyl}] hafnium, dichloro [1,1'-dimethylsilylene (2-methyl-4-phenyl) -Indenyl) {2- (5-methyl-2-furyl) -4-phenyl-indenyl}] hafnium, dichloro [1,1′-dimethylsilylene (2-methyl-4-phenyl-indenyl) {2- (5 -Methyl-2-thienyl) -4-phenyl-indenyl}] hafnium, and the like.

  Of these, dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4-phenyl-indenyl}] hafnium, dichloro [1,1′-dimethyl gel are more preferable. Mylenebis {2- (5-methyl-2-thienyl) -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- (2-naphthyl) -indenyl}] hafnium, dichloro [1, 1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-tert-butylphenyl) -indenyl}] hafnium, dichloro [1,1′- Methylsilylenebis {2- (5-methyl-2-furyl) -4- (4-trimethylsilyl-phenyl) -indenyl}] hafnium, dichloro [1,1'-dimethylsilylenebis {2- (5-methyl-2) -Furyl) -4- (4-i-propylphenyl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-tert-butyl-2-furyl) -4-phenyl-indenyl }] Hafnium.

  Particularly preferred is dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4-phenyl-indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis { 2- (5-Methyl-2-furyl) -4- (4-t-butylphenyl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-Trimethylsilyl-phenyl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-i-propylphenyl)- Indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-tert-butyl-2-furyl) -4-phenyl-indenyl}] hafnium.

(Ii) Component [A-2]: 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, and R ²³ and R ²⁴ are each independently a halogen atom, 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 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, or a halogenated hydrocarbon having 1 to 20 carbon atoms. Group, a C1-C20 oxygen-containing hydrocarbon group, an amino group, or a C1-C20 nitrogen-containing hydrocarbon group. Q ²¹ has a divalent hydrocarbon group having 1 to 20 carbon atoms, a silylene group which may have a hydrocarbon group having 1 to 20 carbon atoms, or a hydrocarbon group having 1 to 20 carbon atoms. Represents a good germylene group. M ²¹ is zirconium or hafnium. ]

R ²¹ and R ²² are each independently a hydrocarbon group having 1 to 6 carbon atoms, preferably an alkyl group, and 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 preferably methyl. , Ethyl, n-propyl.

R ²³ and R ²⁴ each independently contain a halogen atom, silicon having a carbon number of 6 to 30, preferably 6 to 24, or a plurality of hetero elements selected from these. It is a good aryl group. Preferred examples include 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.

Further, the X ²¹ and Y ²¹ are auxiliary ligands to generate an active metallocene having olefin polymerizability reacts with component (B). Therefore, as long as this object is achieved, X ²¹ and Y ²¹ are not limited in the type of ligand, and are independently a hydrogen atom, a halogen atom, or a 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, a phosphorus-containing hydrocarbon group having 1 to 20 carbon atoms, or a silicon-containing hydrocarbon group having 1 to 20 carbon atoms. Show.

Q ²¹ is a binding group that bridges two conjugated five-membered ring ligands, and a silylene having a C 1-20 divalent hydrocarbon group and a C 1-20 hydrocarbon group. Or a germylene group having a hydrocarbon group having 1 to 20 carbon atoms, preferably a substituted silylene group or a substituted germylene group. The substituent bonded to silicon and germanium is preferably a hydrocarbon group 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, Examples thereof include diphenylsilylene, methylphenylsilylene, 9-silafluorene-9,9-diyl, dimethylgermylene, diethylgermylene, diphenylgermylene, methylphenylgermylene and the like.

Further, M ²¹ is zirconium or hafnium, preferably hafnium.

Non-limiting examples of the metallocene compound represented by the general formula (a2) include the following.
However, only representative exemplary compounds are described avoiding many complicated examples. Moreover, although the compound whose center metal is hafnium was described, it is obvious that the same zirconium compound can be used, and various ligands, crosslinking groups, or auxiliary ligands can be arbitrarily used.
Dichloro {1,1′-dimethylsilylenebis (2-methyl-4-phenyl-4-hydroazurenyl)} hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) -4 -Hydroazulenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-t-butylphenyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis { 2-methyl-4- (4-trimethylsilylphenyl) -4-hydroazurenyl}] 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-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (3-chloro-4-trimethylsilylphenyl) -4-hydroazurenyl}] hafnium , Dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (3-methyl-4-trimethylsilylphenyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl -4- (1-naphthyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (2-naphthyl) -4-hydroazurenyl}] hafnium, dichloro [1, 1'-dimethylsilylenebis {2-methyl-4- (4-chloro-2-naphthyl) -4-hydroazule Nil}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (2-fluoro-4-biphenylyl) -4-hydroazulenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis { 2-methyl-4- (2-chloro-4-biphenylyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (9-phenanthryl) -4-hydroazurenyl} ] 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-hydroazurenyl}] hafnium, dichloro [1 1'-dimethylsilylenebis {2-ethyl-4- (3-chloro-4-t-butylphenyl) -4-hydroazurenyl}] hafnium, dichloro [1,1'-dimethylsilylenebis {2-ethyl-4- (3-Methyl-4-trimethylsilylphenyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylgermylenebis {2-methyl-4- (2-fluoro-4-biphenylyl) -4-hydroazurenyl} ] Hafnium, dichloro [1,1'-dimethylgermylenebis {2-methyl-4- (4-tert-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-hydroazurenyl}] hafnium, dichloro [1,1'-dimethylsilylenebis {2-ethyl-4- (2-fluoro- 4-biphenylyl) -4-hydroazurenyl}] hafnium, dichloro [1,1 ′-(9-silafluorene-9,9-diyl) bis {2-ethyl-4- (3,5-dichloro-4-trimethylsilylphenyl) ) -4-hydroazurenyl}] hafnium, and the like.

  Of these, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- Methyl-4- (3-chloro-4-trimethylsilylphenyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-ethyl-4- (2-fluoro-4-biphenylyl) -4 -Hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-ethyl-4- (4-chloro-2-naphthyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-Ethyl-4- (3-methyl-4-trimethylsilylphenyl) -4-hydroazurenyl}] ha Dichloro, [1,1 ′-(9-silafluorene-9,9-diyl) bis {2-ethyl-4- (3,5-dichloro-4-trimethylsilylphenyl) -4-hydroazurenyl}] hafnium, is there.

  Particularly preferably, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-ethyl -4- (2-Fluoro-4-biphenylyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-ethyl-4- (3-methyl-4-trimethylsilylphenyl) -4- Hydroazurenyl}] hafnium, dichloro [1,1 ′-(9-silafluorene-9,9-diyl) bis {2-ethyl-4- (3,5-dichloro-4-trimethylsilylphenyl) -4-hydroazurenyl}] Hafnium.

(2) Catalyst component (B)
Next, the catalyst component (B) used in the method for producing the polypropylene resin (X) of the present invention is an ion-exchange layered silicate.
(I) Types of ion-exchange layered silicate In the present invention, the ion-exchange layered silicate used as a raw material (hereinafter simply abbreviated as “silicate”) is bonded to surfaces formed by ionic bonds or the like. It refers to a silicate compound that has a crystal structure that is stacked in parallel by force and that can contain exchangeable ions. Most silicates are naturally produced mainly as a main component of clay minerals, and therefore often contain impurities (quartz, cristobalite, etc.) other than ion-exchangeable layered silicates. But you can. Depending on the type, amount, particle diameter, crystallinity, and dispersion state of these impurities, it may be preferable to pure silicate, and such a complex is also included in component (B).
In addition, the raw material which concerns on this invention refers to the silicate of the previous step which performs the chemical processing based on this invention mentioned later. Further, the silicate used in the present invention is not limited to a natural product, and may be an artificial synthetic product. You may include them.

Specific examples of the silicate include the following layered silicates described in Haruo Shiramizu “Clay Mineralogy” Asakura Shoten (1995).
That is, montmorillonite, sauconite, beidellite, nontronite, saponite, hectorite, stemite and other smectites, vermiculite and other vermiculites, mica, illite, sericite and sea chlorite and other mica, attapulgite, sepiolite and palygorskite , Bentonite, pyrophyllite, talc, chlorite group, etc.

  The silicate used as a raw material in the present invention is preferably a silicate in which the main component silicate has a 2: 1 type structure, more preferably a smectite group, and particularly preferably montmorillonite. The type of interlayer cation is not particularly limited, but a silicate containing an alkali metal or an alkaline earth metal as a main component of the interlayer cation is preferable from the viewpoint of being easily available as an industrial raw material and inexpensively.

(Ii) Chemical treatment of ion-exchange layered silicate The ion-exchange layered silicate of the catalyst component (B) according to the present invention can be used as it is without any particular treatment, but it is preferable to perform a chemical treatment. . Here, the chemical treatment of the ion-exchange layered silicate may be any of a surface treatment for removing impurities adhering to the surface and a treatment that affects the structure of the clay. Treatment, alkali treatment, salt treatment, organic matter treatment and the like.

<Acid treatment>:
In addition to removing impurities on the surface, the acid treatment can elute part or all of cations such as Al, Fe, Mg, etc. having a 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 salts (described in the next section) and acid may be used for the treatment. The treatment conditions with salts and acids are not particularly limited. Usually, the salt and acid concentrations are 0.1 to 50% by weight, the treatment temperature is room temperature to boiling point, and the treatment time is 5 minutes to 24 hours. It is preferable to carry out the process under the condition of selecting and eluting at least a part of the substance constituting at least one compound selected from the group consisting of ion-exchangeable layered silicates. In addition, salts and acids are generally used in an aqueous solution.
In the present invention, a combination of the following acids and salts may be used as the treating agent. Moreover, the combination of these acids and salts may be sufficient.

<Salt treatment>:
In the present invention, 40% or more, preferably 60% or more of the exchangeable Group 1 metal cation contained in the ion-exchangeable layered silicate before being treated with salts is dissociated from the salts shown below. It is preferable to ion exchange with cations.
The salt used in the salt treatment for the purpose of ion exchange is a group consisting of a cation containing at least one atom selected from the group consisting of group 1 to 14 atoms, a halogen atom, an inorganic acid, and an organic acid. A compound comprising at least one anion selected from the group consisting of at least one anion selected from the group consisting of 2 to 14 atoms, and Cl, Br, I, F, PO. ₄ , SO ₄ , NO ₃ , CO ₃ , C ₂ O ₄ , ClO ₄ , OOCCH ₃ , CH ₃ COCHCOCH ₃ , OCl ₂ , O (NO ₃ ) ₂ , O (ClO ₄ ) ₂ , O (SO ₄ ), At least one anion selected from the group consisting of OH, O ₂ Cl ₂ , OCl ₃ , OOCH, OOCCH ₂ CH ₃ , C ₂ H ₄ O ₄ and C ₅ H ₅ O ₇ Is a compound consisting of

Specific examples of such _{salts, LiF, LiCl, LiBr, LiI} , Li 2 SO 4, Li (CH 3 COO), LiCO 3, Li (C 6 H 5 O 7), LiCHO 2, LiC 2 O 4 , LiClO ₄ , Li ₃ PO ₄ , CaCl ₂ , CaSO ₄ , CaC ₂ O ₄ , Ca (NO ₃ ) ₂ , Ca ₃ (C ₆ H ₅ O ₇ ) ₂ , MgCl ₂ , MgBr ₂ , MgSO ₄ , 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.
Further, Ti (OOCCH ₃ ) ₄ , Ti (CO ₃ ) ₂ , Ti (NO ₃ ) ₄ , Ti (SO ₄ ) ₂ , TiF ₄ , TiCl ₄ , Zr (OOCCH ₃ ) ₄ , Zr (CO ₃ ) ₂ , Zr (NO ₃ ) ₄ , Zr (SO ₄ ) ₂ , ZrF ₄ , ZrCl ₄ , ZrOCl ₂ , ZrO (NO ₃ ) ₂ , ZrO (ClO ₄ ) ₂ , ZrO (SO ₄ ), HF (OOCCH ₃ ) ₄ , HF (CO ₃ ) ₂ , HF (NO ₃ ) ₄ , HF (SO ₄ ) ₂ , HFOCl ₂ , HFF ₄ , HFCl ₄ , V (CH ₃ COCHCOCH ₃ ) ₃ , VOSO ₄ , VOCl ₃ , VCl ₃ , VCl ₄ , VBr _{3 and the} like.

Also, Cr (CH ₃ COCHCOCH ₃ ) ₃ , Cr (OOCCH ₃ ) ₂ OH, Cr (NO ₃ ) ₃ , Cr (ClO ₄ ) ₃ , CrPO ₄ , Cr ₂ (SO ₄ ) ₃ , CrO ₂ Cl ₂ , CrF ₃ , CrCl ₃ , CrBr ₃ , CrI ₃ , Mn (OOCCH ₃ ) ₂ , Mn (CH ₃ COCHCOCH ₃ ) ₂ , MnCO ₃ , Mn (NO ₃ ) ₂ , MnO, Mn (ClO ₄ ) ₂ , MnF ₂ , MnCl ₂ , Fe (OOCCH ₃ ) ₂ , Fe (CH ₃ COCHCOCH ₃ ) ₃ , FeCO ₃ , Fe (NO ₃ ) ₃ , Fe (ClO ₄ ) ₃ , FePO ₄ , FeSO ₄ , Fe ₂ (SO ₄ ) ₃ , FeF ₃ FeCl ₃ , FeC ₆ H ₅ O _{7 and the} like.

In addition, Co (OOCCH ₃ ) ₂ , Co (CH ₃ COCHCOCH ₃ ) ₃ , CoCO ₃ , Co (NO ₃ ) ₂ , CoC ₂ O ₄ , Co (ClO ₄ ) ₂ , Co ₃ (PO ₄ ) ₂ , CoSO ₄ , 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 (OOCCH ₃ ) ₂ , Zn (CH ₃ COCHCOCH ₃ ) ₂ , ZnCO ₃ , Zn (NO ₃ ) ₂ , Zn (ClO ₄ ) ₂ , Zn ₃ (PO ₄ ) ₂ , ZnSO ₄ , ZnF ₂ , ZnCl ₂ , AlF ₃ , AlCl ₃ , AlBr ₃ , AlI ₃ , Al ₂ (SO ₄ ) ₃ , Al ₂ (C ₂ O ₄ ) ₃ , Al (CH ₃ COCHCOCH ₃ ) ₃ , Al (NO ₃ ) ₃ , AlPO ₄ , GeCl ₄ , GeBr ₄ , GeI _{4 and the} like.

<Alkali treatment>:
In addition to the acid and salt treatment, the following alkali treatment or organic matter treatment may be performed as necessary. Examples of the treating agent used in the alkali treatment include LiOH, NaOH, KOH, Mg (OH) ₂ , Ca (OH) ₂ , Sr (OH) ₂ , Ba (OH) _{2 and the} like.

<Organic treatment>:
Examples of the organic treatment agent used for organic treatment include trimethylammonium, triethylammonium, N, N-dimethylanilinium, triphenylphosphonium, and the like.
Examples of the anion constituting the organic treatment agent include hexafluorophosphate, tetrafluoroborate, and tetraphenylborate other than the anion exemplified as the anion constituting the salt treatment agent. However, it is not limited to these.

  Moreover, these processing agents may be used independently and may be used in combination of 2 or more types. These combinations may be used in combination for the treatment agent added at the start of the treatment, or may be used in combination for the treatment agent added during the treatment. Further, the chemical treatment can be performed a plurality of times using 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 component (B).
The heat treatment method of the adsorbed layered silicate adsorbed water and interlayer water is not particularly limited, but it is preferable to select conditions so that interlayer water does not remain and structural destruction does not occur. The heating time is 0.5 hour or longer, preferably 1 hour or longer. At that time, the water content of the component (B) after removal is 3% by weight or less, preferably 0% by weight when the water content is 0% by weight when dehydrated for 2 hours under the conditions of a temperature of 200 ° C. and a pressure of 1 mmHg. Is preferably 1% by weight or less.

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

  The ion-exchange layered silicate can be treated with the component (C) described later before formation of the catalyst or use as a catalyst, which is preferable. Although there is no restriction | limiting in the usage-amount of the component (C) with respect to 1g of ion-exchange layered silicate, Usually, 20 mmol or less, Preferably it is 0.5 mmol or more and 10 mmol or less. There is no limitation on the treatment temperature and time, the treatment temperature is usually 0 ° C. or more and 70 ° C. or less, and the treatment time is 10 minutes or more and 3 hours or less. It is also possible and preferable to wash after the treatment. As the solvent, the same hydrocarbon solvent as that used in the preliminary polymerization and slurry polymerization described later is used.

  The component (B) is preferably a spherical particle having an average particle size of 5 μm or more. If the particle shape is spherical, a natural product or a commercially available product may be used as it is, or a particle whose particle shape and particle size are 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, but commercially available products can also be used.
Moreover, you may use organic substance, an inorganic solvent, inorganic salt, and various binders in the case of granulation.
The spherical particles obtained as described above preferably have a compressive fracture 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 step. In the case of such particle strength, the effect of improving the particle properties is effectively exhibited especially when prepolymerization is performed.

(3) Catalyst component (C)
The catalyst component (C) used in the method for producing the polypropylene resin (X) of the present invention is an organoaluminum compound. The organoaluminum compound used as the component (C) is preferably a compound represented by the general formula: (AlR ¹¹ _q Z _3-q ) _p .
In the present invention, it goes without saying that the compounds represented by this formula can be used alone, in combination of two or more, or in combination. In this formula, R ¹¹ represents a hydrocarbon group having 1 to 20 carbon atoms, and Z represents a halogen atom, a hydrogen atom, an alkoxy group, or an amino group. q represents an integer of 1 to 3, and p represents an integer of 1 to 2, respectively. R ¹¹ is preferably an alkyl group, and Z is a chlorine atom when it is a halogen atom, a C 1-8 alkoxy group when it is an alkoxy group, or a carbon atom number 1 when it is an amino group. An amino group of ˜8 is preferred.

Specific examples of the organoaluminum compound include trimethylaluminum, triethylaluminum, trinormalpropylaluminum, trinormalbutylaluminum, triisobutylaluminum, trinormalhexylaluminum, trinormaloctylaluminum, trinormaldecylaluminum, diethylaluminum chloride, diethylaluminum. Examples thereof include sesquichloride, diethylaluminum hydride, diethylaluminum ethoxide, diethylaluminum dimethylamide, diisobutylaluminum hydride, and diisobutylaluminum chloride. Of these, trialkylaluminum and alkylaluminum hydride having p = 1 and q = 3 are preferable. More preferably, R ¹¹ is a trialkylaluminum having 1 to 8 carbon atoms.

(4) Catalyst Formation / Preliminary Polymerization The catalyst according to the present invention is formed by bringing the above-described components into contact with each other in the (preliminary) polymerization tank simultaneously or continuously, or once or multiple times. be able to.
The contacting of each component is usually performed in an aliphatic hydrocarbon or aromatic hydrocarbon solvent. Although contact temperature is not specifically limited, It is preferable to carry out between -20 degreeC-150 degreeC. As the contact order, any desired combination can be used, but particularly preferable ones for each component are as follows.
When using component (C), before contacting component (A) and component (B), component (A), or component (B), or both component (A) and component (B) The component (C) is contacted, or the component (A) and the component (B) are contacted at the same time as the component (C) is contacted, or the component (A) and the component (B) are contacted. Although it is possible to contact the component (C) later, a method of contacting the component (C) with any of the components (A) and the component (B) is preferable.
Moreover, after contacting each component, it is possible to wash with an aliphatic hydrocarbon or an aromatic hydrocarbon solvent.

The amount of the catalyst components (A), (B) and (C) used in the present invention is arbitrary. For example, the amount of the catalyst component (A) used relative to the catalyst component (B) is preferably in the range of 0.1 μmol to 1000 μmol, particularly preferably 0.5 μmol to 500 μmol, relative to 1 g of the catalyst component (B). The amount of the catalyst component (C) with respect 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 terms of the molar ratio of the transition metal. preferable.

The polypropylene resin (X) of the present invention can be produced by using a catalyst component having a macromer generation ability as a function and a catalyst component having a function of copolymerizing the macromer. Although it is possible to produce by using a single catalyst component having the ability to form the macromer and the ability to have copolymerization at the same time, in order to efficiently produce the polypropylene resin (X) of the present invention, it is possible to produce separately. The method using the catalyst component can be selected. That is, by separately using a component [A-1] capable of generating a macromer and a component [A-2] for copolymerization, it is easy to make a polypropylene resin (X) having the requirements of the present invention. become.
Therefore, the ratio of the component [A-1] and the component [A-2] used in the present invention is arbitrary as long as the properties of the polypropylene resin (X) of the present invention are satisfied, but each component [A-1] The molar ratio of the transition metal of [A-1] to the total amount of [A-2] is preferably 0.30 or more and 0.99 or less.
By changing this ratio, it is possible to adjust the balance between melt tension and catalyst activity. That is, from the component [A-1], a low molecular weight terminal vinyl macromer is produced, and from the component [A-2], a high molecular weight body obtained by copolymerizing a part of the macromer is produced. Therefore, by changing the ratio of the component [A-1], the average molecular weight, molecular weight distribution, bias of the molecular weight distribution toward the high molecular weight side, very high molecular weight component, branch (amount, length, Distribution) can be controlled, whereby the melt physical properties such as strain hardening degree, melt tension, and melt spreadability can be controlled.
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, more preferably 0.40 or more, and still more preferably. It is 0.5 or more. The upper limit is preferably less than 0.90, more preferably 0.8 or less, and still more preferably 0.70 or less in order to efficiently obtain the polymer of the present invention with high catalytic activity. It is a range.
In addition, by using 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 can be subjected to a prepolymerization treatment consisting of a small amount of polymerization by bringing an olefin into contact therewith. By performing the prepolymerization treatment, gel formation can be prevented when the main polymerization is performed. The reason is considered that long chain branching can be uniformly distributed among the polymer particles when the main polymerization is performed.

  The olefin used in the 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 olefin feed method may be any method such as a feed method for maintaining the olefin at a constant rate or a constant pressure in the reaction tank, 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, respectively. The amount of prepolymerization is preferably 0.01 to 100, more preferably 0.1 to 50 with respect to the component (B). Moreover, a component (C) can also be added or added at the time of prepolymerization. It is also possible to wash after the prepolymerization.

  In addition, a method in which a polymer such as polyethylene or polypropylene, or a solid of an inorganic oxide such as silica or titania is allowed to coexist during or after the contact of each component described above is also possible.

4). Polymerization Method Any polymerization method may be adopted as long as the olefin polymerization catalyst containing the component (A), the component (B) and the component (C) is in efficient contact with the monomer.
Specifically, a slurry method using an inert solvent, a so-called bulk method, a solution polymerization method, or a substantially liquid solvent without using an inert solvent as a solvent. A gas phase method can be used. Moreover, the method of performing continuous polymerization and batch type polymerization is also applied. In addition to single-stage polymerization, it is possible to carry out multistage polymerization of two or more stages.

In the case of slurry polymerization, a saturated aliphatic or aromatic hydrocarbon such as hexane, heptane, pentane, cyclohexane, benzene, toluene, or the like is used alone or as a polymerization solvent.
Moreover, it is preferable that polymerization temperature is 0 degreeC or more and 150 degrees C or less. In particular, when bulk polymerization is used, 40 ° C. or higher is more preferable, and 50 ° C. or higher is more preferable. The upper limit is preferably 80 ° C. or lower, and more preferably 75 ° C. or lower.
Furthermore, when using vapor phase polymerization, 40 degreeC or more is preferable, More preferably, it is 50 degreeC or more. 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, 1.5 MPa or more is more preferable, and 2.0 MPa or more is more preferable. The upper limit is preferably 4.0 MPa or less, more preferably 3.5 MPa or less.
Furthermore, when using vapor phase polymerization, 1.5 MPa or more is preferable, and 1.7 MPa or more is more preferable. Further, the upper limit is preferably 2.5 MPa or less, and more preferably 2.3 MPa or less.

Furthermore, as a molecular weight regulator and for activity improvement effect, hydrogen is supplementarily used in a molar ratio of 1.0 × 10 ⁻⁶ or more and 1.0 × 10 ⁻² or less with respect to propylene. It is preferable.
Also, 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 deviation of the molecular weight distribution toward the high molecular weight side, very high molecular weight components, branching (amount, length, Distribution) can be controlled, whereby the melt physical properties such as strain hardening degree, melt tension, and melt spreadability can be controlled.
Therefore, hydrogen is preferably used in a molar ratio to propylene of 1.0 × 10 ⁻⁶ or more, more preferably 1.0 × 10 ⁻⁵ or more, and further preferably 1.0 × 10 ⁻⁴ or more. It is good to use. The upper limit is preferably 1.0 × 10 ⁻² or less, more preferably 0.9 × 10 ⁻² or less, and still more preferably 0.8 × 10 ⁻² or less.

In addition to the propylene monomer, an α-olefin comonomer having 2 to 20 carbon atoms excluding propylene, such as ethylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 4-methyl-1-pentene and the like. Copolymerization is performed using one or two or more selected comonomers.
Therefore, in order to obtain the polypropylene resin (X) of the present invention having a good balance between catalytic activity and melt tension, it is preferable to use ethylene at 15 mol% or less, more preferably 1 to 10.0, relative to propylene. It is mol%, More preferably, it is 1-7.0 mol%.

II. Propylene resin (Y)
In the polypropylene resin composition for sealant of the present invention, the propylene resin (Y) blended together with the polypropylene resin (X) having the long chain branched structure described above is a propylene monopolymer polymerized using a metallocene catalyst. A polymer or a propylene-α-olefin copolymer is used.
The propylene-based resin (Y) may be a propylene homopolymer, or may be a random copolymer or random block copolymer of propylene and ethylene and / or an α-olefin having 4 to 20 carbon atoms. Or a mixture of these components. When using a copolymer of propylene and ethylene and / or an α-olefin having 4 to 20 carbon atoms, the weight fraction of ethylene as a comonomer and the α-olefin having 4 to 20 carbon atoms is preferably 8% by weight. Up to 5% by weight, more preferably up to 5% by weight is preferably used.

  Although MFR of propylene-type resin (Y) is not specifically limited, Preferably it is 1-50 g / 10min, More preferably, it is 3-40 g / 10min, More preferably, it is 5-30 g / 10min. When the MFR is in the range of 1 to 50 g / 10 min, the compatibility with the polypropylene resin (X) is good, the melt-extrusion processing characteristics at the time of co-extrusion are good, the spreadability is excellent, and the speed is high. Co-melt extrusion is possible.

The melting point of the propylene-based resin (Y) is preferably 110 to 170 ° C., more preferably 110 to 168 ° C., further preferably 110 to 150 ° C., particularly preferably 120 to 145 ° C., and the molecular weight distribution is Mw / Mn. Those having a range of preferably 2.0 to 10.0, more preferably 2.5 to 8.0 can be suitably used.
The melting point was determined by using differential operation calorimetry (DSC), once the temperature was raised to 200 ° C. to erase the thermal history, the temperature was lowered to 40 ° C. at a temperature lowering rate of 10 ° C./min, and the temperature rising rate was 10 again. The temperature at the top of the endothermic peak when measured at ° C / min. Mw / Mn is obtained by the same method as described above.

  In the present invention, the propylene-based resin (Y) must be produced with a metallocene-based catalyst for cleanliness (stickiness, bleed out, low elution components, etc.).

  The metallocene catalyst includes (i) a transition metal compound belonging to Group 4 of the periodic table (so-called metallocene compound) containing a ligand having a cyclopentadienyl skeleton, and (ii) a stable ionic state by reacting with the metallocene compound. It is a catalyst comprising a cocatalyst that can be activated and, if necessary, (iii) an organoaluminum compound, and any known catalyst can be used. The metallocene compound is preferably a bridged metallocene compound capable of stereoregular polymerization of propylene, and more preferably a bridged metallocene compound capable of isoregular polymerization of propylene.

  Examples of (i) metallocene compounds include JP-A-60-35007, JP-A-63-130314, JP-A-63-295607, JP-A-1-275609, JP-A-2-41303, and JP-A-2-41303. JP-A-2-131488, JP-A-2-76887, JP-A-3-163888, JP-A-4-30087, JP-A-4-21694, JP-A-5-43616, JP-A-5-209913, JP-A-6 No. 239914, JP-A-7-504934, JP-A-8-85708, etc. can be preferably used.

  More specifically, methylene bis (2-methylindenyl) zirconium dichloride, ethylenebis (2-methylindenyl) zirconium dichloride, ethylene 1,2- (4-phenylindenyl) (2-methyl-4-phenyl) -4H-azulenyl) zirconium dichloride, isopropylidene (cyclopentadienyl) (fluorenyl) zirconium dichloride, isopropylidene (4-methylcyclopentadienyl) (3-t-butylindenyl) zirconium dichloride, dimethylsilylene (2- Methyl-4-t-butyl-cyclopentadienyl) (3′-t-butyl-5′-methyl-cyclopentadienyl) zirconium dichloride, dimethylsilylenebis (indenyl) zirconium dichloride, dimethylsilylenebis (4,5 6,7-tetrahydroindenyl) zirconium dichloride, dimethylsilylene bis [1- (2-methyl-4-phenylindenyl)] zirconium dichloride, dimethylsilylene bis [1- (2-ethyl-4-phenylindenyl)] Zirconium dichloride, dimethylsilylenebis [4- (1-phenyl-3-methylindenyl)] zirconium dichloride, dimethylsilylene (fluorenyl) t-butylamidozirconium dichloride, methylphenylsilylenebis [1- (2-methyl-4, (1-naphthyl) -indenyl)] zirconium dichloride, dimethylsilylenebis [1- (2-methyl-4,5-benzoindenyl)] zirconium dichloride, dimethylsilylenebis [1- (2-methyl-4-phenyl-) 4H-azuleni ] Zirconium dichloride, dimethylsilylenebis [1- (2-ethyl-4- (4-chlorophenyl) -4H-azulenyl)] zirconium dichloride, dimethylsilylenebis [1- (2-ethyl-4-naphthyl-4H-azurenyl) ] Zirconium dichloride, diphenylsilylene bis [1- (2-methyl-4- (4-chlorophenyl) -4H-azulenyl)] zirconium dichloride, dimethylsilylene bis [1- (2-ethyl-4- (3-fluorobiphenyl) Ryl) -4H-azurenyl)] zirconium dichloride, dimethylgermylenebis [1- (2-ethyl-4- (4-chlorophenyl) -4H-azurenyl)] zirconium dichloride, dimethylgermylenebis [1- (2-ethyl) -4-phenylindenyl)] zirconium di Zirconium compounds such as chloride can be exemplified.

In the above, compounds in which zirconium is replaced with titanium or hafnium can be used in the same manner. It is also preferable to use a mixture of a zirconium compound and a hafnium compound. Further, the chloride can be replaced with other halogen compounds, hydrocarbon groups such as methyl, isobutyl and benzyl, amide groups such as dimethylamide and diethylamide, alkoxide groups such as methoxy group and phenoxy group, hydride groups and the like.
Of these, metallocene compounds obtained by crosslinking an indenyl group or an azulenyl group with silicon or a germyl group are particularly preferable.

The metallocene compound may be used by being supported on an inorganic or organic compound carrier.
The carrier is preferably an inorganic or organic porous compound. Specifically, ion-exchange layered silicate, zeolite, SiO ₂ , Al ₂ O ₃ , silica alumina, MgO, ZrO ₂ , TiO ₂ , B Organic compounds composed of inorganic compounds such as ₂ O ₃ , CaO, ZnO, BaO, ThO ₂ , porous polyolefins, styrene-divinylbenzene copolymers, olefin-acrylic acid copolymers, or a mixture thereof. It is done.

  (Ii) As a co-catalyst that can be activated to a stable ionic state by reacting with a metallocene compound, an organoaluminum oxy compound (for example, an aluminoxane compound), an ion-exchange layered silicate, a Lewis acid, a boron-containing compound, an ionic compound Preferred examples include fluorine-containing organic compounds.

  (Iii) Examples of organoaluminum compounds include trialkylaluminum such as triethylaluminum, triisopropylaluminum, triisobutylaluminum, dialkylaluminum halide, alkylaluminum sesquihalide, alkylaluminum dihalide, alkylaluminum hydride, organoaluminum alkoxide. Preferably mentioned.

  The production method of the propylene-based resin (Y) is not particularly limited, and can be produced by any of the conventionally known slurry polymerization method, bulk polymerization method, gas phase polymerization method, and the like. It is also possible to produce a propylene homopolymer and a propylene-α-olefin copolymer using a polymerization method.

  In addition, as the propylene-based resin (Y), commercially available products can be used. For example, a trade name “Wintech” (registered trademark) series and a trade name “Wellnex” (registered trademark) manufactured by Nippon Polypro Co., Ltd. Those in the series can be used as appropriate.

III. Other components In the polypropylene resin composition for sealant of the present invention, if necessary, other resins other than polypropylene resin (X) and propylene resin (Y) (for example, polyethylene polymers, various elastomers, etc.), In addition, additives such as an antiblocking agent, an antioxidant, a weather resistance stabilizer, an antistatic agent, a release agent, a flame retardant, a wax, an antifungal agent, an antibacterial agent, a filler and a foaming agent may be blended.

IV. Melt extrusion processing The polypropylene resin composition for sealant of the present invention is used by being laminated on both surfaces via an intermediate layer by coextrusion.

The intermediate layer may be any resin that can be co-extruded. Specifically, polyester resins such as polyethylene terephthalate and polybutylene terephthalate, saponified ethylene-vinyl acetate copolymer, polyvinyl chloride, polyvinylidene chloride, Thermoplastic resins such as polyethylene, polypropylene, poly-4-methyl-1-pentene, polycarbonate resin, polyamide 6, polyamide 66, polyamide 6.66, polyamide 12 and other polyamide resins can be mentioned, among which polypropylene is preferable.
The final form is preferably a thermoplastic resin film or sheet, may be uniaxially or biaxially stretched, and is particularly preferably biaxially stretched polypropylene.

As a preferable final form, the thickness of the formed polypropylene film is usually 1 to 100 μm, preferably 3 to 80 μm, particularly preferably 10 to 60 μm.
The obtained laminate can be further subjected to various film processing such as metal vapor deposition, corona discharge treatment, and printing.

V. Applications When the polypropylene film for sealant according to the present invention is formed into a bag shape by a bag making machine, a film laminated by coextrusion is improved in sealing strength.
And it is preferable that the polypropylene film which concerns on this invention is used for a fusing seal.
Moreover, it is preferable to melt the polypropylene film according to the present invention to form a fusing seal bag.

  EXAMPLES Next, although an Example demonstrates this invention further more concretely, this invention is not limited to a following example, unless the summary is exceeded. In addition, the physical-property measurement, analysis, etc. in the following Examples are according to the following method and the text.

(1) Melt flow rate (MFR):
In accordance with JIS K6921-2, “Plastics—Polypropylene (PP) molding and extrusion materials—Part 2: How to make test pieces and properties” Test flow: 230 ° C., load 2 .16 kgf) was measured. The unit is g / 10 minutes.
(2) Molecular weight and molecular weight distribution (Mw, Mn, Q value):
It was measured by the method described in the present specification by gel permeation chromatography (GPC).
(3) mm fraction:
The measurement was carried out by the method described in the present specification using GSX-400 and FT-NMR manufactured by JEOL. The unit is%.

(4) Measurement of ethylene content:
It was measured by the method described in the present specification.
(5) Elongation viscosity:
It was measured by the method described in the present specification.
(6) Composition analysis:
A calibration curve was prepared by chemical analysis according to JIS method and measured by fluorescent X-ray.
(7) Melting point (Tm):
It was measured by the method described in the present specification.

1. Synthesis of catalyst (preliminary polymerization catalyst) [Synthesis Example 1 of catalyst component [A-1]]:
(1) Synthesis of dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-i-propylphenyl) indenyl}] hafnium: (component [A-1] (Synthesis of Complex 1):
The synthesis of rac-dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-i-propylphenyl) indenyl}] hafnium is disclosed in JP 2012-149160 A. The same procedure as described in Synthesis Example 1 was performed.

[Synthesis Example 2 of catalyst component [A-2]]:
(2) Synthesis of rac-dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) -4-hydroazurenyl}] hafnium: (synthesis of component [A-2] (complex 2) ):
The synthesis of rac-dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) -4-hydroazurenyl}] hafnium is carried out according to the method described in Example 7 of JP-A-11-240909. As well as.

[Synthesis Example of Catalyst Component [B]]
(3) Chemical treatment of ion-exchange layered silicate:
In a separable flask, 96% sulfuric acid (668 g) was added to 2264 g of distilled water, and then 400 g of montmorillonite (Mizusawa Chemical Benclay SL: average particle size 19 μm) was added as a layered silicate. The slurry was heated at 90 ° C. for 210 minutes. The reaction slurry was added to 4000 g of distilled water and filtered to obtain 810 g of a cake-like solid.
Next, 432 g of lithium sulfate and 1924 g of distilled water were added to the separable flask to make a lithium sulfate aqueous solution, and the entire amount of the cake-like solid was charged. The slurry was reacted at room temperature for 120 minutes. To this slurry, 4000 g of distilled water was added and then filtered to obtain a cake-like solid. The operation of adding 4000 g of distilled water to the cake-like solid and filtering was repeated, and the slurry was washed until the pH of the slurry became 5 to 6, followed by filtration to obtain 760 g of a cake-like solid.
The obtained solid was preliminarily dried overnight at 100 ° C. under a nitrogen stream, and then coarse particles of 53 μm or more were removed and further dried at 200 ° C. for 2 hours under reduced pressure to obtain 220 g of chemically treated montmorillonite.
The composition of this chemically treated montmorillonite 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].

(4) Catalyst preparation and prepolymerization:
In a three-necked flask (volume: 1 L), 10 g of the chemically treated montmorillonite obtained above was added, and heptane (66 mL) was added to form a slurry. 0.0 mL) was added and the mixture was stirred for 1 hour, and then washed with heptane until the residual liquid ratio became 1/100 to make the total volume 50 mL.
In another flask (volume: 200 mL), rac-dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) prepared in Synthesis Example 1 of the catalyst component [A-1] was prepared. ) -4- (4-i-propylphenyl) indenyl}] hafnium (105 μmol) was dissolved in toluene (21 mL) to prepare solution 1. Furthermore, in another flask (volume: 200 mL), rac-dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) prepared in Synthesis Example 2 of the catalyst component [A-2] was prepared. ) -4-hydroazulenyl}] hafnium (45 μmol) was dissolved in toluene (9 mL) to prepare solution 2.

After adding triisobutylaluminum (0.42 mmol: 0.6 mL of a heptane solution with a concentration of 143 mg / mL) to the 1 L flask containing the chemically treated montmorillonite, the above solution 1 (21 mL) was added and stirred for 20 minutes at room temperature. did.
Then, after further adding triisobutylaluminum (0.18 mmol: 0.25 mL of a heptane solution having a concentration of 143 mg / mL), the above solution 2 was added and stirred at room temperature for 1 hour.
Thereafter, 170 mL of heptane was added, and this slurry was introduced into a 1 L autoclave.
After the internal temperature of the autoclave was set to 40 ° C., propylene was fed at a rate of 5 g / hour, and prepolymerization was performed while maintaining the temperature at 40 ° C. for 4 hours. Thereafter, propylene feed was stopped and residual polymerization was carried out for 1 hour. After removing the supernatant of the obtained catalyst slurry by decantation, triisobutylaluminum (6 mmol: 8.5 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 26.1 g of a prepolymerized catalyst 1. The prepolymerization ratio (value obtained by dividing the amount of prepolymerized polymer by the amount of solid catalyst) was 1.61.

2. Production and property evaluation of polypropylene resin (X) [Polymerization Example 1]
The 3 L autoclave was dried well by circulating nitrogen under heating, and then the inside of the tank was replaced with propylene and cooled to room temperature. After adding 2.86 mL of a heptane solution of triisobutylaluminum (143 mg / mL), 117 Nml of hydrogen was introduced, followed by 49 g of ethylene.
Next, after introducing 750 g of liquid propylene, the temperature was raised to 70 ° C.
Thereafter, 15 mg of the prepolymerized catalyst 1 in a weight excluding the prepolymerized polymer was pumped to the polymerization tank with high-pressure argon to initiate polymerization. After maintaining at 70 ° C. for 1 hour, 5 ml of ethanol was injected to stop the polymerization. As a result, 225 g of a polymer was obtained.
5 g of the obtained polymer was dissolved in hot xylene and then precipitated with a large amount of ethanol. After filtration, it was dried under reduced pressure to obtain a sample for analysis.
Table 3 shows the evaluation results of the obtained polymer (polymer 1).

[Polymerization Example 2]
Polymerization was performed in the same manner as in Polymerization Example 1 except that 130 Nml of hydrogen, 6 g of ethylene, and 40 mg of the prepolymerized catalyst 1 were introduced in a weight excluding the prepolymerized polymer. As a result, 240 g of a polymer was obtained.
Table 3 shows the evaluation results of the obtained polymer (polymer 2).

[Polymerization Example 3]
Polymerization was performed in the same manner as in Polymerization Example 1 except that 58 Nml of hydrogen, 62 g of ethylene, and 20 mg of the prepolymerized catalyst 1 were used in a weight excluding the prepolymerized polymer. As a result, 240 g of a polymer was obtained.
The evaluation results of the obtained polymer (polymer 3) are shown in Table 3.

[Polymerization Example 4]
Polymerization was performed in the same manner as in Polymerization Example 1 except that 47 Nml of hydrogen, 0 g of ethylene, and 70 mg of the prepolymerized catalyst 1 were used in a weight excluding the prepolymerized polymer. As a result, 245 g of a polymer was obtained.
Table 3 shows the evaluation results of the obtained polymer (polymer 4).

[Polymerization Example 5]
Polymerization was carried out in the same manner as in Polymerization Example 1, except that 105 Nml of hydrogen, 45 g of ethylene, and 15 mg of the prepolymerized catalyst 1 were used in a weight excluding the prepolymerized polymer. As a result, 220 g of a polymer was obtained.
Table 3 shows the evaluation results of the obtained polymer (polymer 5).

  Moreover, what illustrated the relationship of the hydrogen supply amount (Nml), the ethylene supply amount (g), and the strain hardening degree of the obtained polymer about the polymerization examples 1-5 is shown in FIG. It can be seen that the strain hardening degree tends to decrease as the hydrogen supply amount and the ethylene supply amount increase. In FIG. 3, it can be seen that the conditions for the hydrogen supply amount and the ethylene supply amount are preferably in the upper right region of the broken line as the polymerization conditions for obtaining a polymer having a strain hardening degree of 6 or less.

3. Evaluation and application example of polypropylene resin composition [Example 1]
In Example 1, the polymer 1: 30% by weight produced in Polymerization Example 1 and the following PP 1: 70% by weight were mixed with a Henschel mixer and then melt extruded at a temperature of 220 ° C. with an extruder having a screw diameter of 50 mmΦ. Thus, pellets of the resin composition were obtained.
The obtained pellets were extruded at a resin temperature of 230 ° C. using a 35 mmφT die molding machine, and then solidified with a cooling roll set at 30 ° C. to obtain a single layer film having a thickness of 30 μm. Dispersibility was evaluated using this single layer film. The results are shown in Table 4.
The obtained pellets were put into an extruder having a diameter of 30 mm on both surface layers, and from a T die having a width of 300 mm via an intermediate layer of polypropylene (manufactured by Nippon Polypro Co., Ltd., trade name: Novatec (registered trademark) FL203D), After co-extrusion at a resin temperature of 240 ° C., the film was solidified with a cooling roll set at 30 ° C. to obtain a film original.
The original film was stretched 5 times in the longitudinal direction by a longitudinal stretching machine set at 100 ° C., and stretched 7 times in the transverse direction by a transverse stretching machine set at 160 ° C., and the surface layer was 1 μm / intermediate layer 18 μm / surface layer. A biaxially stretched film having a thickness of 1 μm and an overall thickness of 20 μm was obtained.
The quality of the obtained biaxially stretched film was evaluated. The results are shown in Table 4.

[Examples 2 to 8 and Comparative Examples 1 to 9]
In Examples 2 to 8 and Comparative Examples 1 to 9, as in Example 1, pellets of the resin composition were obtained with the compositions and ratios shown in Tables 4 and 5, and single layer films and biaxially stretched films were obtained.
The evaluation results of the single layer film and the biaxially stretched film are shown in Tables 4 and 5.

  The outline of the resin used in the above Examples / Comparative Examples is shown below. In Examples and Comparative Examples, the properties of polypropylene resin compositions and propylene resins were measured and evaluated according to the following evaluation methods.

(1) Resin used: Propylene resin (Y)
(I) PP1;
Product name “Wintech (registered trademark) WFW5T” manufactured by Nippon Polypro Co., Ltd., propylene-ethylene random copolymer with metallocene catalyst, MFR = 3.5 g / 10 min, flexural modulus = 1350 MPa, Vicat softening temperature = 130 ° C, melting point = 143 ° C.
(Ii) PP2;
Product name “Wintech (registered trademark) WFX5233” manufactured by Nippon Polypro Co., Ltd., propylene-ethylene random copolymer with metallocene catalyst, MFR = 7 g / 10 min, flexural modulus = 900 MPa, Vicat softening temperature = 117 ° C., Melting point = 130 ° C.
(Iii) PP3;
Made by Nippon Polypro Co., Ltd., trade name “Wellnex (registered trademark) RFG4VM”, propylene-ethylene random block copolymer by metallocene catalyst, MFR = 6 g / 10 min, flexural modulus = 280 MPa, Vicat softening temperature = 115 ° C. Melting point = 128 ° C.

(2) Evaluation method (i) Dispersibility (FE):
A test piece having a size of 20 cm × 15 cm was cut out from the single layer film, and the number of fish eyes having a size of 0.2 mm or more was visually counted to calculate the number per 1 m ² area. The average value of five test pieces was determined, and the dispersibility was evaluated.
The evaluation criteria are as follows, and Δ or more was regarded as acceptable.
○: Less than 10 △: 10 or more and less than 20 ×: 20 or more and less than 30 ××: 30 or more

(Ii) Perspective (LSI):
The LSI of the biaxially stretched film was measured using an LSI meter (N207) manufactured by Toyo Seiki Seisakusho. LSI measures the amount of light scattering at a small angle and is a measure of the transparency of a film that matches the visual feeling. The higher the value, the worse the transparency, and the lower the value, the better the transparency.

(Iii) Fusing heat seal strength:
Using a bag making machine equipped with a 400 ° C. fusing seal bar, a biaxially stretched film is made, and a strip with a width of 15 mm is prepared so that the seal portion is at the center between the scores, and then JIS K7127 (1999) “ The fusing seal strength was measured according to the method described in “Plastics—Test Method for Tensile Properties—Part 3: Test Conditions for Films and Sheets”.

As is clear from Table 3, the polypropylene resin (X) of the present invention is a propylene polymer satisfying a predetermined melt flow rate, Q value, the amount of components soluble in p-xylene and the degree of strain hardening. I understand that.
Therefore, as is clear from Table 4, the polypropylene resin (X) of the present invention was used as the first component of the resin component, and blended with the propylene-based resin (Y) as the second component of the resin component. The resin composition of No. 8 has high fusing seal strength, excellent transparency, and excellent dispersibility.
On the other hand, the resin compositions of Comparative Examples 1 to 9 that do not use the two components of the polypropylene resin (X) and the propylene-based resin (Y) of the present invention as the resin components are as shown in Table 5, with a fusing seal strength and a transparency. In Comparative Examples 1-3, transparency and dispersibility are good, but the fusing seal strength is poor. In Comparative Examples 4-6, the fusing seal strength is good. Fish eyes in transparency and dispersibility were poor, and in Comparative Examples 7 to 9, the fusing seal strength and transparency were good, but the fish eyes in dispersibility were poor.

  The polypropylene resin composition for sealant of the present invention has high fusing seal strength and is excellent in cleanliness (stickiness, bleed out, low elution component, etc.). Therefore, it can be suitably used as an OPP film for fusing sealing or a fusing sealing bag, and industrial applicability is extremely high.

Claims (9)

Polypropylene resin (X) having a characteristic of the following (Xi) to (X-iii) and having a long chain branched structure (X) 3 to 50% by weight and polymerized using a metallocene catalyst, The number of fish eyes of 0.2 mm or more is 10 when a T-die single layer film having a thickness of 30 μm and containing 50 to 97% by weight of a propylene resin (Y) made of a coalescence or propylene-α-olefin copolymer is used. Polypropylene resin composition for sealant, characterized in that it is less than pieces / m ² .
(Xi): Melt flow rate (MFR: 230 ° C., 2.16 kg load) is 1.0 to 80.0 g / 10 min.
(X-ii): Melting peak temperature (Tm) measured by DSC method (differential scanning calorimeter measurement) is 110 to 145 ° C.
(X-iii): The degree of strain hardening (λmax) in the measurement of elongational viscosity is 1.5 to 6.0.
The polypropylene resin composition for sealant according to claim 1, wherein the polypropylene resin (X) has the following properties (X-iv).
(X-iv): The ratio (Q value) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is 2.5 to 5.5. The polypropylene resin composition for sealant according to claim 1 or 2, wherein the polypropylene resin (X) has the following properties (X-v) to (X-vi).
(Xv): The ratio (CXS) of the component that is soluble in p-xylene at 25 ° C. is 0.01 to 5.0% by weight.
(X-vi): The mm fraction of three propylene units linked by ¹³ C-NMR is 95% or more.   The polypropylene resin composition for sealant according to any one of claims 1 to 3, wherein the propylene resin (Y) is a propylene-α-olefin copolymer.   The propylene resin (Y) is a propylene-α-olefin copolymer having an MFR of 1 to 10 g / 10 min, and the polypropylene resin composition for sealant according to any one of claims 1 to 4. object.   The polypropylene resin composition for sealant according to any one of claims 1 to 5, wherein the propylene resin (Y) is a propylene-α-olefin copolymer having a melting point of 110 to 150 ° C.   The polypropylene-based resin composition for sealant according to any one of claims 1 to 6, wherein the polypropylene-based film is laminated by coextrusion through an intermediate layer and stretched at least in a uniaxial direction. .   The polypropylene film according to claim 7, wherein the polypropylene film is used for a fusing seal.   A fusing-seal bag, which is formed by fusing the polypropylene film according to claim 7 or 8.

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