JPH11166084A - Polypropylene-based resin composition and film made therefrom - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polypropylene-based resin composition that contains a polypropylene prepared by polymerization with a homogeneous catalyst such as a metallocene catalyst, having a sharp molecular weight distribution, and that shows improved moldability, secondary fabrication property (low- temperature heat-sealing properties), and a film made therefrom. SOLUTION: This polypropylene-based resin composition comprises (A) 99-50 wt.% of a propylene homopolymer that has an intrinsic viscosity [η] of 0.5-5.0 dl/g, the molecular weight distribution (Mw /Mn ) of <=3.5, the isotactic pentad fraction of 40-99 mol.% (mmmm molar fraction) and has a relation to the melting point (Tm deg.C) of Tm <=[mmmm]+65; and (B) 1-50 wt.% of a propylene homopolymer that forms eutectic crystals under the quenching conditions, when it is formed into film together with the component (A).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a propylene homopolymer composition having improved moldability and secondary workability (low-temperature heat sealability) and a film thereof. For more information,
Crystallization characteristics of a polypropylene with a sharp molecular weight distribution polymerized using a homogeneous catalyst such as a metallocene catalyst, ie, a propylene homopolymer close to a single component (supercooling degree (melting point and crystallization temperature) Difference) is large, the cooling effect during thermoforming is not sufficiently effective, and the shape retention is poor)
To improve moldability and secondary workability (low-temperature heat sealability)
The present invention relates to an improved propylene homopolymer composition and a film thereof.

[0002]

2. Description of the Related Art In the field of extrusion molding for forming films and sheets, metallocene-based catalysts have problems with moldability and low-temperature heat sealability which have not been a problem with polypropylene polymerized using a Ziegler-based supported catalyst. It became apparent in polypropylene polymerized using a homogeneous catalyst such as

That is, the cooling effect during thermoforming is not sufficiently effective, the shape retention is poor, and troubles such as meandering, neck-in, unevenness in thickness accuracy, and insufficient expression of stretching strength are observed. In addition, there are also problems with secondary workability such as poor sealing during high-speed bag making. For such a problem,
Although a general modification method by adding a so-called nucleating agent (Japanese Patent Application Laid-Open No. 9-296084) and the like have been proposed, the selection of the additive gives transparency, odor, etc. to the films and sheets.
Difficulty in reducing impact strength, stability against heat history (laminating process), safety, etc., and formation of gel-like substance by synergistic action with other additives such as anti-blocking agent It is not always enough due to some aspects.

[0004]

DISCLOSURE OF THE INVENTION The present invention relates to a polypropylene having a sharp molecular weight distribution, which is polymerized by using a homogeneous catalyst such as a metallocene catalyst, and has high moldability and secondary processing (low-temperature heat sealability). An object of the present invention is to provide an improved propylene homopolymer composition and a film thereof.

[0005]

Means for Solving the Problems As a result of intensive studies on the above-mentioned problems, the present inventors have found that a polypropylene polymerized using a homogeneous catalyst is close to a single component, that is, the polymer has a single structure and molecular weight. It is difficult to crystallize because of this (high degree of supercooling), and it is found that it causes troubles such as moldability, and a blend of two or more polypropylenes with a specific crystallization temperature difference forms a eutectic By doing so, the inventors have found that it is easier to crystallize and effective for solving troubles, and have completed the present invention described below. [1] (A) 99 to 50% by weight of a propylene homopolymer having the following properties (a1) to (a4), (a1) intrinsic viscosity [η] is 0.5 to 5.0 deciliter / g,
(A2) the molecular weight distribution ( _Mw / _Mn ) is 3.5 or less, and (a3) the isotactic pentad fraction (mmm
(mol fraction%) is 40 to 99 mol%, and (a
4) The relationship between the isotactic pentad fraction (mmmm mole fraction%) and the melting point ( _Tm ° C.) satisfies the formula (I) _Tm ≦ [mmmm] +65 (I) (B) ( A) A polypropylene resin composition comprising 1 to 50% by weight of a propylene homopolymer which forms a eutectic under the quenching condition during film formation with the component (A). [2] The crystallization temperature (T _cB ° C) of the component (B) measured by a differential scanning calorimeter is the same as the crystallization temperature (T _cA ) of the component (A).
The polypropylene resin composition according to claim 1, which is 0 to 40 ° C higher than the temperature. [3] (A ′) a propylene homopolymer having an isotactic pentad fraction (mmmm fraction) of 80 to 9
Polymerization was performed using a metallocene catalyst having an intrinsic viscosity [η] of 1.0 to 2.0 deciliters / g and a molecular weight distribution (M _w / M _n ratio) of 3.5 or less. 99 to 50% by weight of the propylene-based polymer is (B ′) a propylene homopolymer having an intrinsic viscosity [η] of 0.01 to
1.0 deciliter / g, and the molecular weight distribution (M _w / M
_A polypropylene resin composition comprising 1 to 50% by weight of a propylene polymer polymerized using a metallocene catalyst having an _n ratio of 3.5 or less. [4] A film formed using the propylene polymer composition according to any one of [1] to [3].

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below. [1] The resin composition of the first invention of the present invention has (A) 99 to 50% by weight of a propylene homopolymer having the following properties (a1) to (a4), and (a1) intrinsic viscosity [η]. 0.5
(A2) the molecular weight distribution ( _Mw / _Mn ) is 3.5 or less, and (a3) the isotactic pentad fraction (mmmm mole fraction%) is 40.
(A4) isotactic pentad fraction (mmmm mol fraction%) and melting point (T _m ).
) Satisfies the formula (I) _Tm ≦ [mmmm] +65 (I) (B) A propylene homopolymer that forms a eutectic with the component (A) under rapid cooling conditions during film forming It is a polypropylene resin composition comprising 1 to 50% by weight.

Since the propylene homopolymer of the component (A) having a narrow molecular weight distribution is close to a single component, polymers having different stereoregularities and low molecular weight polymers which play the role of crystal nuclei in the initial stage of crystallization may be used. Because it is small, it is difficult to crystallize,
Supercooling degree (temperature difference between melting point and crystallization temperature) showing crystallization characteristics is large. In the present invention, the propylene homopolymer of the component (A) having a narrow molecular weight distribution forms a eutectic with another propylene homopolymer of the component (B) under quenching conditions at the time of film forming, so that a single polypropylene is obtained. In such a case, a cast film having improved moldability, which is difficult to achieve, and a balance between rigidity and seal temperature can be obtained.

In general, when a crystal is measured by a DSC method in a crystal growth close to an equilibrium state, a eutectic crystal may not be easily formed, and the degree of supercooling may be slightly reduced. However, during thermoforming of a film sheet, quenching is performed by a quenching operation (crystal growth that proceeds in a non-equilibrium state), so that a eutectic is likely to be formed, and the formation of the eutectic provides an effect of improving physical properties and formability. .

That is, the component (B) of the present invention comprises the component (A)
Components and quenching conditions during film forming (resin temperature at die exit: 191 ° C, chill roll temperature: 30 ° C, film thickness: 2
5 μ and a take-up speed of 6 m / min). Incidentally, the eutectic crystallization of the polymer in the present invention is carried out by adjusting the state of the film immediately after molding by a differential scanning calorimeter (DSC method) as described below and then immediately starting to raise the temperature. Judgment is made based on the fact that the peak top is singular. This eutectic of the polymers is such that one polymer forms an initial crystal with the other polymer as a crystal nucleus, and then
It is presumed to have grown.

[0010] The component (A) used in the present invention, propylene simple
The homopolymer is polymerized with a homogeneous catalyst such as a metallocene catalyst.
Polypropylene, but is not supported by Ziegler catalysts, etc.
Even if it is a supported catalyst, it has a performance close to that of a homogeneous system.
If you can use it. That is, the catalyst used for polymerization
The limit of propylene homopolymer without being limited to a medium
The viscosity [η] is 0.5 to 5.0 deciliter / g;
Molecular weight distribution (M_w/ M _n) Is 3.5 or less,
Tactic pentad fraction (mmmm mole fraction%) of 4
0-99 mol%, preferably 80-99 mol%
Yes, and isotactic pentad fraction (mmmm
Mole fraction%) and melting point (T_m° C) is given by the formula (I) T_m.Ltoreq. [Mmmm] +65 (I).

If the intrinsic viscosity [η] is less than 0.5 deciliter / g, mechanical strength such as film tensile strength and rigidity is insufficient, and if it is more than 5.0 deciliter / g, cast molding and extrusion molding are difficult. And also
When the molecular weight distribution (M _w / M _n ) exceeds 3.5, the balance between the film rigidity and the heat sealing property is reduced,
The blocking resistance may decrease. Furthermore,
If the isotactic pentad fraction (mmmm mol fraction%) is less than 40 mol%, the film rigidity is low,
If it exceeds 99 mol%, the impact resistance of the film is poor, which is not preferable.

The relational expression (I) between the isotactic pentad fraction (mmmm mole fraction%) and the melting point (T _m ° C) is obtained by peroxidizing polypropylene having a wide molecular weight distribution obtained with a conventional catalyst. This means that polypropylene having a molecular weight distribution ((M _w / M _n ) of 3.5 or less by the decomposition treatment using a material is excluded.
The propylene homopolymer of the component has a stereoregularity [mmm
m] and propylene homopolymer having a molecular weight close to that of a single component, whereas the object to be excluded is stereoregularity [mm
mm), and the melting point (T _m ° C) inherent to the resin composition tends to appear high due to the component having high stereoregularity [mmmm], and is excluded from the formula (I). Is done. When the relation of the formula (I) is not satisfied, the balance between the rigidity of the obtained film and the heat sealing temperature is inferior.

The propylene homopolymer of the component (B) is
Any material may be used as long as it forms a eutectic with the propylene homopolymer of the component (A). In general, if the propylene homopolymer of the component (A) has a stereoregularity or a molecular weight different from that of the propylene homopolymer, a crystal nucleus can be induced to form a eutectic. Accordingly, for example, a propylene homopolymer having a smaller molecular weight than the component (A) can be mentioned.

In the resin composition of the present invention, the component (A) is 99 to 50% by weight, more preferably 99 to 80% by weight.
Component (B) is 1 to 50% by weight, more preferably 1 to 20% by weight.
It is a polypropylene-based resin composition consisting of% by weight.
When the proportion of the component (B) is less than 1% by weight, the heat sealability and moldability deteriorate, and when it exceeds 50% by weight, the balance between the heat sealability and the film rigidity decreases.

A film cast using the resin composition with improved crystallization characteristics of the present invention has a large effect of improving the physical properties and moldability, and has a tensile modulus (TM) in the MD direction of the cast film. (MPa)) and the heat sealing temperature (HST (° C.)) are more preferably represented by the formula (II) TM ≧ 22 × HST-1850 (II), more preferably TM ≧ 22 × HST-1800 (II) ') Is expected to be satisfied.

According to the effect of the present invention, the heat sealing temperature (H
ST (° C.) tends to decrease (at lower temperatures,
The film peel strength reaches a certain level), and the film tensile modulus (rigidity) also tends to increase.
It is expressed by

[2] The second invention of the present invention is the first invention, wherein the crystallization temperature (T _cB ° C) of the component (B) measured by a differential scanning calorimeter is the same as that of the component (A). The polypropylene resin composition is 0 to 40 ° C. higher than the crystallization temperature (T _cA ° C.).

That is, as for the component (B) which can form a eutectic with the component (A), the effect of improving the physical properties increases as the difference in crystallization temperature increases, but it is difficult to form a eutectic when the temperature exceeds 40 ° C. In some cases, the effect of improving the properties of the present invention cannot be expected. More preferably, T _cB is 10 to 40 more than T _cA.
° C higher.

[3] The third invention of the present invention relates to (A ') a propylene homopolymer, wherein the isotactic pentad fraction (mmmm mole fraction%) is 80 to 99%, and A propylene polymer having a limiting viscosity [η] of 1.0 to 2.0 deciliters / g and a molecular weight distribution (Mw / Mn ratio) of 3.5 or less is polymerized with a metallocene catalyst of 99 to 50 wt. % Of a (B ′) propylene homopolymer, a metallocene catalyst having an intrinsic viscosity [η] of 0.01 to 1.0 and a molecular weight distribution (Mw / Mn) of 3.5 or less. Propylene polymer 1 polymerized by
A polypropylene-based resin composition containing 50% by weight.

(1) Component (A ') The component (A') is a propylene homopolymer polymerized using a metallocene catalyst, and is prepared in a small amount (0.5%).
(Mole% or less) or a propylene polymer prepolymerized with ethylene or an α-olefin having 4 to 20 carbon atoms, and an isotactic pentad fraction (mmmm mole fraction%) showing stereoregularity of polypropylene. ) Is 80-99
%, More preferably 85 to 97%, and the intrinsic viscosity [η] is 1.0 to 2.0 deciliter / g, more preferably 1.5 to 1.8 deciliter / g, and the molecular weight distribution (Mw / Mn ratio) is 3.5 or less, more preferably 3.
Use a value of 0 or less.

The isotactic pentad fraction (mmmm mole fraction%) referred to in the present invention is defined by Cheng HN, Ewen J.
^{A., Macromol.cem., 13 C-} N listed in 1989,190,1350
Based on the assignment of the peaks in the MR spectrum, the ratio (%) of the five propylene structural units having the meso structure (mmmm structure in which five methyl groups are arranged in the same direction) is included. For short, it is also called a mesopentad fraction.

This isotactic pentad fraction is
If it is less than 80%, the film rigidity may be insufficient, and if it exceeds 99%, the impact resistance of the film may be inferior, which is not preferable. In general, the intrinsic viscosity [η] is preferably 1.0 to 2.0 deciliter / g mainly from the viewpoint of film formability, and if less than 1.0 deciliter / g, the film tensile strength, rigidity and the like are not good. Enough
If it exceeds 2.0 deciliters / g, the fluidity is low and molding may be difficult.

Furthermore, the molecular weight distribution (Mw / Mn ratio)
If it exceeds 3.5, the balance between the film rigidity and the heat sealability may be reduced, or the blocking resistance may be reduced. The propylene polymer of the component (A ′) used in the present invention is composed of a transition metal compound belonging to Group 4 of the periodic table having a cyclopentadienyl ring and methylaluminoxane or a transition metal compound belonging to Group 4 of the periodic table. It can be produced by polymerizing in the presence of a metallocene catalyst comprising a compound which reacts to form an ionic complex and an organoaluminum compound.

The transition metal compound of Group 4 of the periodic table having a cyclopentadienyl ring as the main catalyst includes a cycloalkadienyl group or a substituted product thereof, specifically, an indenyl group, a substituted indenyl group and a part thereof. Zirconium, titanium and hafnium compounds having a polydentate compound as a ligand in which at least two groups selected from the group consisting of hydrides are bonded via a lower alkylene group or a silylene group. That is, the transition metal compound is HHBrintzin
Ger et al, J. Organometal. Chem., 288, 63 (1985), ethylene-bis- (indenyl) zirconium dichloride, and ethylene-bis- (indenyl) zirconium dichloride, described in J. Am. Chem. Soc., 109, 6544 (1987).
Bis- (indenyl) hafnium dichloride, H. Yamaza
dimethylsilylbis (2,4-dimethylcyclopentadienyl) zirconium dichloride, dimethylsilylbis (2,4,5-trimethylcyclopentadienyl) zirconium dichloride described in ki et al, Chemistry Letters, 1853 (1989), or these. Is a stereorigid chiral compound of zirconium and hafnium compounds such as the complex of hafnium dichloride.

More specifically, ethylene bis (indenyl) zirconium dichloride, ethylene bis (4,
5,6,7-tetrahydro-1-indenyl) zirconium dichloride, ethylenebis (4-methyl-1-indenyl) zirconium dichloride, ethylenebis (5-
Methyl-1-indenyl) zirconium dichloride, ethylenebis (6-methyl-1-indenyl) zirconium dichloride, ethylenebis (7-methyl-1-indenyl) zirconium dichloride, ethylenebis (2,3
-Dimethyl-1-indenyl) zirconium dichloride, ethylenebis (4,7-dimethyl-1-indenyl) zirconium dichloride, ethylenebis (indenyl) hafnium dichloride, ethylenebis (4,5,
6,7-tetrahydro-1-indenyl) hafnium dichloride, ethylenebis (4-methyl-1-indenyl) hafnium dichloride, ethylenebis (5-methyl-1-indenyl) hafnium dichloride, ethylenebis (6-methyl-1- Indenyl) hafnium dichloride, ethylenebis (7-methyl-1-indenyl) hafnium dichloride, ethylenebis (2,3-dimethyl-)
1-indenyl) hafnium dichloride, ethylenebis (4,7-dimethyl-1-indenyl) hafnium dichloride, dimethylsilylenebis (indenyl) zirconium dichloride, dimethylsilylenebis (indenyl)
Hafnium dichloride, dimethylsilylenebis (4-methylindenyl) zirconium dichloride, dimethylsilylenebis (indenyl) hafnium dichloride, dimethylsilylenebis (2,4,5-trimethylcyclopentadienyl) zirconium dichloride, dimethylsilylenebis (2 4,5-trimethylcyclopentadienyl) hafnium dichloride, dimethylsilylenebis (2,4-dimethylcyclopentadienyl) zirconium dichloride, dimethylsilylenebis (2,4-dimethylcyclopentadienyl) hafnium dichloride, dimethylsilylenebis (3-methylcyclopentadienyl)
Zirconium dichloride, dimethylsilylenebis (3-
Methylcyclopentadienyl) hafnium dichloride,
Examples thereof include dimethylsilylenebis (2-methyl-4-phenylindenyl) zirconium dichloride and dimethylsilylenebis (benzoindenyl) zirconium dichloride.

Also, (dimethylsilylene) (dimethylsilylene) -bis (indenyl) zirconium dichloride, (ethylene) (ethylene) -bis (indenyl) zirconium dichloride, (ethylene) (ethylene) -bis (3-methylindenyl) Zirconium dichloride,
(Ethylene) (ethylene) -bis (4,7-dimethylindenyl) zirconium dichloride and the like, and those obtained by substituting zirconium in these compounds with hafnium or titanium.

Compounds that form an ionic complex by reacting with a transition metal compound of Group 4 of the periodic table of the co-catalyst include triphenylcarbinium tetrakis (pentafluorophenyl) borate, N, N-dimethyl Anilinium tetrakis (pentafluorophenyl) borate,
Compounds containing a tetra (pentafluorophenyl) borate anion such as lithium tetrakis (pentafluorophenyl) borate, triphenylcarbinium tetrakis (pentafluorophenyl) aluminate, N,
Tetra (pentafluorophenyl) aluminate anion-containing compounds such as N-dimethylanilinium tetrakis (pentafluorophenyl) aluminate and lithium tetrakis (pentafluorophenyl) aluminate are preferably used.

Further, as the organoaluminum compound,
It has at least one Al-C bond in the molecule. Specific examples of such organoaluminum compounds include triethylaluminum, triisobutylaluminum, trialkylaluminum such as trihexylaluminum, diethylaluminum halide, dialkylaluminum halide such as diisobutylaluminum halide, a mixture of trialkylaluminum and dialkylaluminum halide, and tetraethylaluminum. Examples thereof include alkylalumoxanes such as dialumoxane and tetrabutylalumoxane.

Of these organoaluminum compounds, trialkylaluminum, a mixture of trialkylaluminum and dialkylaluminum halide, and alkylalumoxane are preferred.
Triisobutylaluminum, a mixture of triethylaluminum and diethylaluminum chloride and tetraethyldialumoxane are preferred. As the organic aluminum, triethylaluminum, triisobutylaluminum and the like are preferably used.

These metallocene catalysts and / or cocatalysts may be used in a state of being supported, and examples of the carrier include organic compounds such as polystyrene and inorganic oxides such as silica and alumina. The polymerization method may be any of a bulk polymerization method, a solution polymerization method, a gas phase polymerization method, a suspension polymerization method, and the like, and may be any of a batch method and a continuous method.

Also, a small amount of α-olefin such as ethylene, propylene, 1-butene, 4-methyl-
Prepolymerization may be performed with 1-pentene or the like. The polymerization temperature is usually in the range of −50 to 250 ° C., preferably 0 to 150 ° C., the polymerization time is usually in the range of 1 to 10 hours, and the pressure is usually normal pressure to 300 kg / cm ² -G. Range.

(2) Component (B ') The component (B') is a propylene homopolymer polymerized by using a metallocene catalyst, and a small amount (0.5%)
Mol% or less) or a propylene polymer prepolymerized with ethylene or an α-olefin having 4 to 20 carbon atoms, and has an intrinsic viscosity [η] of 0.01 to 1.0 deciliter /
g, more preferably 0.1 to 0.8 deciliter / g, and a molecular weight distribution (Mw / Mn ratio) of 3.5 or less, more preferably 3.0 or less.

The intrinsic viscosity [η] is 0.01 deciliter /
If it is smaller than g, it may cause stickiness of the film, etc. If it exceeds 1.0 deciliter / g, the effect of improving the balance between film rigidity and heat sealability is lost. Further, when the molecular weight distribution (Mw / Mn ratio) exceeds 3.5, the balance between the film rigidity and the heat sealability may be reduced, or the blocking resistance may be reduced.

Isotactic pendant fraction (mmm
The (m fraction) is not limited for the component (B ′), but is preferably 80 to 99% from the viewpoint of film rigidity and the like. Further, it preferably has a higher _Tc than the _Tc (crystallization temperature) of the component (A '). The polymerization of the component (B ′) is basically carried out using the same metallocene catalyst and co-catalyst as used in the propylene polymer of the component (A ′) and by the same polymerization method. Can be.

(3) Blending The propylene polymer composition of the present invention has a blending ratio (weight% ratio) of the components (A ') and (B') of 99 to 50: 1.
Consists of 50. It is more preferably from 99 to 75: 1 to 25, and still more preferably from 99 to 90: 1 to 10.

If the content of the component (B ') is less than 1%, the heat sealing property may be deteriorated. If it exceeds 50%, the balance between the film rigidity and the heat sealing property may be reduced. In blending the components (A) and (B) or the components (A ') and (B') according to the present invention, various additives such as a nucleating agent, a heat stabilizer, an antioxidant, and a weathering agent are used. A neutralizing agent, a slip agent, an anti-blocking agent, a lubricant, a dye, a pigment, a filler, an anti-fogging agent, an antistatic agent, and the like can be added as necessary.

The propylene polymer composition of the present invention is prepared by mixing the above components with a Henschel mixer, a V blender, a ribbon blender, a tumbler blender, or the like, and then mixing them with a single-screw extruder, a multi-screw extruder, a kneader, a Banbury mixer, or the like. Kneading can be performed by a kneading machine.

[4] The propylene-based polymer composition of the present invention can be further used for injection molding, blow molding, extrusion molding, etc., and is particularly preferably used for film applications such as cast molding and inflation molding. I can do it. The thickness of the film depends on the application, but is usually about 5 to 500 μm. Also, the film is not only used in a single layer,
It can be suitably used for a multilayer film by a co-extrusion film forming method, and can also be suitably used as a stretched film.

[0039]

EXAMPLES The present invention will be described in further detail with reference to Examples. In addition, each test evaluation method and judgment method are as shown below. [1] Measurement method of intrinsic viscosity [η] The intrinsic viscosity [η] (deciliter / g) is measured in decalin at 135 ° C.

[2] Measurement method of molecular weight distribution Mw / Mn ratio Mw and Mw / Mn were measured by using the following apparatus and conditions. GPC measuring instrument Column: ShowexUT manufactured by Showa Denko KK
806L Infrared detector: IR detector for liquid chromatogram Infrared detection flow cell: KBr cell (optical path length 1 mm) Measurement conditions Solvent: o-dichlorobenzene Measurement temperature: 135 ° C. Flow rate: 1.0 ml / min Sample concentration: 2 Milligram / milliliter Injection amount: 200 μl Infrared absorption wavelength: 3.42 μm

[3] Isotactic pentad fraction The isotactic pentad fraction (mmmm mole fraction%) is determined by Cheng HN, Ewen JA, Macromol. Cem., 1989, 19
Of the five propylene structural units based on the assignment of peaks in the ¹³ C-NMR spectrum described in 0,1350, those having a meso structure (mmmm structure in which five methyl groups are arranged in the same direction) are included. A ratio (%) was determined by the following apparatus and conditions. Apparatus: JNM-EX400 type NM manufactured by JEOL Ltd.
R device Sample concentration: 220 mg / NMR solvent 3 ml NMR solvent: 1,2,4-trichlorobenzene / heavy benzene (90 / 10vol%) Measurement temperature: 130 ° C Pulse width: 45 ° Pulse repetition time: 4 seconds Integration count: 10,000 times [4] The relationship between the isotactic pentad fraction (mmmm mole fraction%) and the melting point ( _Tm ° C) satisfies the formula (I) _Tm ≦ [mmmm] +65 (I) When it was satisfied, it was OK, and when it was not satisfied, it was NO. [5] Tensile modulus Measured by a tensile test according to JIS K7127NI. The measurement conditions are as follows: the crosshead speed is 500 mm / min, and the measurement direction is the machine direction (MD direction). [6] Tensile modulus (TM (MPa)) and heat sealing temperature (H
ST (° C.)) is satisfied when the relationship of the formula (II) TM ≧ 22 × HST-1850 (II) is satisfied, and NO when the relationship is not satisfied. [7] Film Impact (FI) The film impact indicates the impact breaking strength, and was measured using a 1-inch impact head with a film impact tester manufactured by Toyo Seiki.

[8] Heat seal temperature (HST) The heat seal temperature (HST) is in accordance with JIS K-1707.
It is measured in accordance with. After sealing under the following fusion conditions, leave at room temperature for 24 hours.
The peel strength was measured by a T-type peeling method at a rate of 00 mm / min, and the temperature at which the peel strength was 300 g / 15 mm was calculated from the obtained seal strength-peel strength curve, and this temperature was defined as the heat seal temperature. . Film thickness is 25μ
m is a representative value. Sealing conditions Sealing time: 2 seconds Sealing area: 15 × 10 mm Sealing pressure: 5.3 kg / cm ² Sealing temperature: Several points so that the heat sealing temperature can be interpolated. The temperature of the heat seal bar is calibrated with a surface thermometer.

[0043]

[9] Measurement of melting point ( _Tm ° C) and crystallization temperature ( _Tc ° C) of resin Differential scanning calorimeter (DSC, manufactured by Parking Elmer)
Using -7), 10 mg of the sample was previously melted at 230 ° C. for 3 minutes in a nitrogen atmosphere, and then 0 ° C. at 10 ° C./min.
Cool down to The peak top of the maximum peak of the crystallization exothermic curve obtained at this time was defined as the crystallization temperature (T _c ° C). Further, after holding at 0 ° C. for 3 minutes, the temperature was raised at a rate of 10 ° C./min, and the peak top of the maximum peak of the melting endothermic curve was defined as the melting point (T _m ° C.).

[10] Method of judging eutectic by direct melting endothermic curve of film sample Differential scanning calorimeter (manufactured by Parking Elmer, DSC
Using -7), a 10 mg film sample immediately after casting is kept under a nitrogen atmosphere at 0 ° C. for 3 minutes, and then heated at a rate of 10 ° C./min. Therefore, it is determined that a eutectic is formed. In addition, the peak observed at the time of actual measurement is derived from components other than the resin component, in addition to two or more separated peak tops derived from the melting point of the resin component constituting the film, or a single peak top in some cases. Peaks that appear to be shoulders and traces are observed. Therefore, the judgment is as follows: 判定 す る: It is judged that a single peak top or a single peak top with a shoulder or trace overlapped is forming a eutectic ×: Two or more peak tops or two or more peak tops If shoulders and traces overlap, determine that they do not form a eutectic

Example 1 (1) Production of Component (A-1) 4.0 liters of toluene and 8 parts of triisobutylaluminum were placed in a 10 liter stainless steel autoclave.
Mmol, 20 μmol of tetrakispentafluorophenyl borate dimethyl anilium salt, 40
° C, 10 mmol of hydrogen was added, and the total pressure was 7.0 k.
Propylene was introduced up to g / cm ² -G. here,
5 μmol of (1,2′-ethylene) (2,1′-ethylene) -bis (indenyl) hafnium dichloride was added to initiate polymerization. Propylene was supplied by a pressure regulator so that the pressure became constant. Two hours later, the content was taken out and dried under reduced pressure to obtain 820 g of polypropylene. The polypropylene obtained here is
The mesopentad fraction (mmmm) is 91%, the intrinsic viscosity [η] is 1.5 deciliters / g, and the molecular weight distribution (M _w /
_Mn ratio) was 1.9.

(2) Production of component (B-1) 400 ml of toluene, 1 mmol of triisobutylaluminum, and 4 μmol of tetrakispentafluorophenylborate dimethyl anilium salt were charged into a 1 liter stainless steel autoclave, and 55
° C, 4 mmol of hydrogen was added, and the total pressure was 7.0 kg.
/ Propylene up to / cm ² -G. here,
1 μmol of (1,2′-ethylene) (2,1′-ethylene) -bis (indenyl) hafnium dichloride was added to initiate polymerization. Propylene was supplied by a pressure regulator so that the pressure became constant. One hour later, the content was taken out, poured into a large amount of methanol, filtered, and dried to obtain 75 g of polypropylene. The polypropylene obtained here has a mesopentad fraction (mmm
m) is 90% and the intrinsic viscosity [η] is 0.5 deciliter /
g, molecular weight distribution (M _w / M _n ratio) was 2.0.

(3) Mixing and kneading 91% by weight of the above-mentioned A-1 component and 9% by weight of the B-1 component
, And furthermore, as an antioxidant "Irganox 1
010 "(manufactured by Ciba Specialty Chemicals, trade name) 750 ppm by weight," Irganox 168 "
(Ciba Specialty Chemicals, trade name) 7
50 wt ppm, calcium stearate 500 wt ppm as neutralizing agent, erucamide 1 as slip agent
000 wt ppm, and 1800 wt ppm of a silica-based anti-blocking agent as an anti-blocking agent, were added to a single screw extruder (TLC35-20 manufactured by Tsukada Juki Seisakusho, Ltd.).
) To obtain a resin composition.

(4) Film molding The T-die cast molding method was used to make a 2
Using a 0mmφT die cast molding machine, film thickness 25μm
Was formed under the following conditions. Die outlet temperature 1
91 ° C, chill roll temperature 30 ° C, take-off speed 6m / min,
After film formation, aging was performed at 40 ° C. for 24 hours. The tensile modulus, film impact, and heat sealing temperature of the obtained film were measured and evaluated, and the molding stability of the film was evaluated. The results are shown in Table 1. The molding stability of the film was very good, and no neck-in phenomenon was observed.

Example 2 In Example 1, (A-
1) The resin was similarly changed except that the component was changed from 91% by weight to 90% by weight, the component (B-1) was changed to the following component (B-2), and the weight was changed from 9% by weight to 10% by weight. After adjustment, the film was formed into a film and evaluated. Table 1 shows the results. The molding stability of the film was very good, and no neck-in phenomenon was observed. In addition, no occurrence of bumps or the like was observed.

Production of Component (B-2) 1) Preparation of Magnesium Compound A reaction tank equipped with a stirrer (500 liter internal volume) was sufficiently replaced with nitrogen gas, and 97.2 kg of ethanol and 64 iodine were added.
Then, 0 g and 6.4 kg of metallic magnesium were charged and reacted under reflux conditions with stirring until hydrogen gas was no longer generated from within the system to obtain a solid reaction product. The reaction liquid containing the solid reaction product was dried under reduced pressure to obtain a target magnesium compound (solid product). 2) Adjustment of solid catalyst component A reaction vessel equipped with a stirrer (internal volume 5
00 liters), 30 kg of the magnesium compound (not pulverized), 1 purified heptane (n-heptane)
50 liters, 4.5 liters of silicon tetrachloride and 5.4 liters of di-n-butyl phthalate were added. 90 in the system
C., and after stirring, 144 liters of titanium tetrachloride were added thereto and reacted at 110.degree. C. for 2 hours. Then, a solid component was separated and washed with purified heptane at 80.degree. Furthermore, after adding 288 liters of titanium tetrachloride and reacting at 110 ° C. for 2 hours, it was sufficiently linearized with purified heptane at 80 ° C. to obtain a solid catalyst component. 3) Pretreatment 230 liters of purified heptane (n-heptane) was charged into a 500 liter reactor equipped with a stirrer, and 25 kg of the solid catalyst component and triethylaluminum were added in an amount of 1: 1 based on titanium atoms in the solid catalyst component. 0mol / mo
1, 1.8 mol of dicyclopentyldimethoxysilane
/ Mol. Thereafter, propylene was introduced until the propylene partial pressure reached 0.3 kg / cm ² G, and 2
The reaction was performed at 5 ° C. for 4 hours. After the reaction, the solid catalyst component was washed several times with purified heptane, and further supplied with carbon dioxide,
Stirred for 24 hours. 4) Main polymerization Propylene was introduced into a polymerization apparatus having an internal volume of 200 liters and equipped with a stirrer. , And 1 mmol / kg-PP of dicyclopentyldimethoxysilane, respectively, and a polymerization temperature of 80 ° C. and a polymerization pressure (total pressure) of 28 k
The reaction was performed at g / cm ² G. In this example, the amount of hydrogen supplied was adjusted so as to have a predetermined molecular weight. The isotactic pentad fraction of the obtained polymer (B) is 9
At 7.6 mol%, the melt index is 5.9 g / 1.
It was 0 minutes. As a result of composition analysis (gas chromatography) of the gas portion in the polymerization apparatus during the polymerization, the hydrogen concentration was 4.2 mol%.

[Embodiment 3] In Embodiment 1, (A-
1) The component is replaced with the following component (A-2), and 91% by weight
From 90% by weight to 90% by weight, component (B-1) was changed to component (B-2), and the weight was changed from 9% by weight to 10% by weight. The film was evaluated. Table 1 shows the results. The film had good molding stability and good releasability on the chill roll surface.
In addition, no occurrence of bumps or the like was observed.

Preparation of Component (A-2) 1) Preparation of Catalyst Preparation of (1,2′-ethylene) (2,1′-ethylene) -bis (3-methylindene) 1.12 g (3.94 mmol) of '-ethylene) (2,1'-ethylene) -bis (indene) was dissolved in 50 ml of dehydrated ether. -7
After cooling to 8 ° C., 5.01 ml of a 1.57 mol / l hexane solution of n-butyllithium (n-butyllithium: 7.87 mmol) was added dropwise over 30 minutes, and the temperature was raised to room temperature. Stirred for hours. The ether solvent was distilled off under reduced pressure, and the residue was washed with hexane to obtain 1.12 g of a dilithium salt as an ether adduct.
(3.02 mmol) was obtained. This dilithium salt was dissolved in 50 ml of dehydrated tetrahydrofuran, and
Cooled to ° C. To this solution, 10 ml of a tetrahydrofuran solution containing 0.42 ml (6.74 mmol) of methyl iodide was added dropwise for 20 minutes, and the temperature was raised to room temperature, followed by stirring for 8 hours. After evaporating the solvent under reduced pressure, the residue was extracted with ethyl acetate. After washing the extracted solution with water and drying the organic layer over anhydrous magnesium sulfate,
The mixture was separated by filtration and the filtrate was dried under reduced pressure to obtain 0.87 g (2.78 mmol) of (1,2′-ethylene) (2,1′-ethylene) -bis (3-methylindene), which was the target substance. Obtained in a yield of 70.5%. It was present as an isomer mixture of double bonds in the five-membered ring moiety. One of this ^one
When the 1 H-NMR was determined, the following results were obtained. ¹ H
_{-NMR (CDCL 3) (δ,} ppm): 0.7~1.7
(Methyl group), 2.5 to 3.4 (proton on a five-membered ring),
6.8 to 7.5 (benzene ring proton)

Production of dilithium salt of (1,2'-ethylene) (2,1'-ethylene) -bis (3-methylindene) Under a nitrogen stream, (1,2'-ethylene) (2,1'- 0.87 g of ethylene) -bis (3-methylindene) (2.
(78 mmol) dissolved in 35 mmol of ether.
Cooled to ° C. To this solution is added n-butyllithium 1.5
After 3.7 ml of a 7 mol / l hexane solution (n-butyllithium 5.81 mmol) was added dropwise over 30 minutes, the mixture was heated to room temperature and stirred for 8 hours. After evaporating the solvent under reduced pressure, the residue was washed with hexane to convert the dilithium salt into an ether adduct (1.03 g).
(2.58 mmol) was obtained in a yield of 92.8%. When the ¹ H-NMR of this product was determined, the following results were obtained. ¹ H-NMR (THF-d ₈ ) (δ, ppm):
2.20 (s, 6H), 3.25 (s, 8H), 6.0
~ 7.4 (8H)

Preparation of (1,2′-ethylene) (2,1′-ethylene) -bis (3-methylindenyl) zirconium dichloride (1,2′-ethylene) (2,1′-ethylene) -bis 1.03 g (2.58 mmol) of an ether adduct of (3-methylindene) dilithium salt was suspended in 25 ml of toluene and cooled to -78 ° C. To this, a suspension of zirconium tetrachloride (0.60 g, 2.58 mmol) in toluene (20 ml) was added over 20 minutes.
After heating to room temperature and stirring for 8 hours, the toluene supernatant was separated by filtration. Residue is 2 in 50 ml of dichloromethane.
Extracted times. After the solvent was distilled off under reduced pressure, the residue was recrystallized from dichloromethane / hexane to give (1,1).
2'-ethylene) (2,1'-ethylene) -bis (3-
Methylindenyl) zirconium dichloride 0.21
g was obtained with a yield of 17.3%. When the ¹ H-NMR of this product was determined, the following results were obtained. ¹ H-NMR (C
_{DCl 3): 2.48 (6H,} s), 3.33~3.85
(8H), 6.9-7.6 (8H)

2) Polymerization In a stainless steel autoclave having an internal volume of 10 liters, 5 liters of heptane, 5 mmoles of triisobutylaluminum, and 19 mmoles of methylaluminoxane (manufactured by Albemarle Co., Ltd.) were adjusted to 19 mmols in terms of aluminum as described in 1) above. 2'-ethylene) (2,1'-ethylene)
A catalyst component obtained by precontacting 19 micromoles of -bis (3-methylindenyl) zirconium dichloride in toluene for 30 minutes was added, the temperature was raised to 40 ° C, and the total pressure was 8.0.
Propylene gas was introduced up to kg / cm ² G. During the polymerization, propylene gas was supplied by a pressure regulator so that the pressure became constant. After one hour, the content was taken out and dried under reduced pressure to obtain polypropylene.

[Comparative Example 1] (B-1)
-1) A resin was prepared and a film was formed and evaluated in the same manner as in Example 1 except that no component was added. Table 1 shows the results. At the time of forming the film, a neck-in phenomenon was observed. [Comparative Example 2] A resin was prepared and a film was formed in the same manner as in Example 1 except that the component (A-2) was not used and the component (B-1) was not blended. Table 1 shows the results. The peelability of the film on the chill roll surface was extremely poor, and film forming was impossible.

Comparative Example 3 In Example 1, (A-
A resin was prepared in the same manner as in Example 1 except that E2900 manufactured by Idemitsu Petrochemical Co., which was obtained by using a nonmetallocene catalyst (titanium / magnesium catalyst) instead of the component (1) and the component (B-1). After adjustment, the film was formed into a film and evaluated. Table 1 shows the results. The film molding was good,
Chill roll stains were noticeable.

Comparative Example 4 In Example 1, (A-
1) The component is replaced with the component (A-2) and 91% by weight.
The resin was prepared in the same manner except that the component (B-1) was changed to the component (B-2), and the weight was changed from 9% by weight to 50% by weight. The film was evaluated. Table 1 shows the results. Film molding is
Good and no bad phenomenon was observed, but some bumps occurred.

Comparative Example 5 In Example 1, (A-
1) The component was changed from 91% by weight to 95% by weight, and the component (B-1) was replaced with high-density polyethylene (IDEMITSU HDPE 640UF manufactured by Idemitsu Petrochemical Co., Ltd.), and 9% by weight.
The resin was prepared in the same manner except that the amount was changed from 5% by weight to 5% by weight. Table 1 shows the results. The film molding was good and no particularly bad phenomenon was observed, but physical properties could not be measured because a large amount of bumps were generated.

[0060]

[Table 1]

[0061]

According to the resin composition of the present invention, a film having a lower heat sealing temperature and excellent moldability can be obtained while maintaining excellent film rigidity (tensile modulus) and film impact. In Example 3, in combination with the component (B) having a crystallization temperature difference of 53.5 ° C., the presence or absence of the eutectic was determined, but the double peak top was observed on the melting point measurement of DSC, and the eutectic was observed. Indicates a state that is difficult to generate. On the other hand, when the component (A-1) alone shown in Comparative Example 1 is used alone, the moldability is insufficient, and the balance between the heat sealing temperature and the tensile modulus represented by the formula (II) is poor. When the component (A-2) alone used in Comparative Example 2 is used, the film at the time of molding has extremely poor releasability on the chill roll surface, and cannot be molded. In Comparative Example 3, the decomposed polypropylene having a narrow molecular weight distribution is inferior in the balance between the heat sealing temperature and the tensile modulus represented by the formula (II). Comparative Example 4
When the compounding ratio of the component (B) is out of the range, the balance between the heat sealing temperature and the tensile modulus shown by the formula (II) is inferior.
Further, in the resin composition with the high-density polyethylene shown in Comparative Example 5, no eutectic was observed.

Claims (4)

[Claims] (A) 99 to 50% by weight of a propylene homopolymer having the following properties (a1) to (a4): (a1)
The intrinsic viscosity [η] is 0.5 to 5.0 deciliter / g, (a2) the molecular weight distribution (M _w / M _n ) is 3.5 or less, and (a3) the isotactic pentad fraction ( mm
(mm mole fraction%) is 40 to 99 mole%, and (a
4) The relationship between the isotactic pentad fraction (mmmm mole fraction%) and the melting point ( _Tm ° C.) satisfies the formula (I) _Tm ≦ [mmmm] +65 (I) (B) ( A) A polypropylene resin composition comprising 1 to 50% by weight of a propylene homopolymer which forms a eutectic under the quenching condition during film formation with the component (A). 2. The crystallization temperature (T _cB ℃) of the component (B) measured by a differential scanning calorimeter is 0 to 40 ° C. higher than the crystallization temperature (T _cA ℃) of the component (A). The polypropylene-based resin composition as described in the above. (A ') a propylene homopolymer,
Isotactic pentad fraction (mmmm fraction) of 8
0 to 99% and an intrinsic viscosity [η] of 1.0 to 2.
0 deciliter / g, and the molecular weight distribution (M _w / M
_(n ratio) is 3.5 to 50% by weight of a propylene-based polymer polymerized using a metallocene-based catalyst of 3.5 or less,
(B ′) a metallocene-based propylene homopolymer having an intrinsic viscosity [η] of 0.01 to 1.0 deciliter / g and a molecular weight distribution (M _w / M _n ratio) of 3.5 or less. Propylene polymers 1 to 50 polymerized using a catalyst
A polypropylene-based resin composition which is blended by weight. 4. A film formed from the propylene polymer composition according to claim 1.