JPH0848836A - Polypropylene resin composition - Google Patents

Abstract

PURPOSE:To obtain a composition having a specific cross-linked structure, capable of giving molded products with good balance between rigidity and impact resistance and high heat resistance. CONSTITUTION:This polypropylene resin composition comprises crystalline polypropylene, another kind of crystalline polypropylene having a boiling xylene insolubles of <=10wt.% and a cross-linked structure with the molecular weight of 1,000-300,000 between the cross linked points for boiling xylene solubles, and talc.

Description

Detailed Description of the Invention

[0001]

This invention relates to polypropylene compositions containing talc. More specifically, the present invention relates to a polypropylene resin composition containing talc and polypropylene having a specific structure and having an excellent balance of rigidity and impact.

[0002]

2. Description of the Related Art Polypropylene is used for various purposes because it is lightweight and excellent in mechanical strength. Further, talc has been mixed for the purpose of improving rigidity and heat resistance. However, in the conventional method, although talc can be mixed to improve rigidity and heat resistance, physical properties such as impact resistance are deteriorated, and therefore talc is further treated with various coupling agents or maleic anhydride is used. Polymers having a polar group introduced, which are grafted with a glycidyl compound or the like, have been added.

[0003]

Although the conventional method can provide some degree of improvement in physical properties, it is at best enough to prevent a decrease in impact strength, and the improvement in terms of physical properties is insufficient. Is. It has been desired to develop a polypropylene resin composition containing talc, which has excellent rigidity, heat resistance, and impact strength.

[0004]

[Means for Solving the Problems] The present inventors completed the present invention by intensively searching for a polypropylene resin composition having excellent physical properties by solving the above problems.

That is, according to the present invention, (A) crystalline polypropylene and (B) the boiling xylene-insoluble portion is 10% by weight or less, and the molecular weight between the crosslinking points of the boiling xylene-soluble portion is in the range of 1,000 to 300,000. A polypropylene resin composition comprising crystalline polypropylene having a structure and (C) talc.

Crystalline polypropylene used in the present invention
(A) is not particularly limited as long as it is a polypropylene having crystallinity, and examples thereof include not only a propylene homopolymer but also a copolymer of propylene and two or more other olefins having 2 to 20 carbon atoms. . Random copolymers with other olefins or block copolymers are also included. For example, a binary or ternary copolymer of propylene and an olefin such as ethylene, butene, pentene, hexene, cyclopentene, cyclohexene, 3methylpentene, and 4methylpentene may be used. In addition, polypropylene and poly-α-olefins such as polybutene, polypentene, polyhexene, polyheptene, and polyoctene; cyclic polyolefins such as polycyclopentene and polynorbornene; or composites of propylene / ethylene rubber (EPR) and propylene / ethylene / diene rubber. Can also be used. In these copolymers and composites, the proportion of components other than propylene used is less than 10% by weight in random copolymerization, and in the case of block copolymerization, polymerization with propylene alone is 50% by weight or more of the whole. Preferably.

These polypropylenes are already commercially available and can be produced using a catalyst. As the catalyst used for producing polypropylene, a catalyst which is industrially used for producing polypropylene is used. For example, a titanium trichloride catalyst or a carrier catalyst in which titanium trichloride or titanium tetrachloride is supported on a carrier such as magnesium chloride is used.
Further, a homogeneous catalyst represented by a combination of dicyclopentadienyl zirconium dichloride and aluminoxane can be used. As the polymerization method, a conventional polymerization method such as a solvent polymerization method, a bulk polymerization method or a gas phase polymerization method is used.

In the present invention, the molecular weight between the crosslinking points means a value obtained by dividing the molecular weight of the crystalline polymer by the number of crosslinking points contained in the crystalline polymer.

In the present invention, the value of the molecular weight between cross-linking points obtained by dividing the molecular weight of the boiling xylene-soluble part of crystalline polypropylene by the number of cross-linking points contained in the polypropylene is
Very important.

The crystalline polypropylene used in the present invention has a crosslinked structure in which the boiling xylene-insoluble portion is 10% by weight or less, and the boiling xylene-soluble portion has a crosslinked structure having a molecular weight in the range of 1,000 to 300,000. The crystalline polypropylene (B) has) means that polypropylene or a polypropylene having a structure in which the main chain is branched into two or more in the middle of the polymer main chain is chemically crosslinked by reacting with a crosslinking agent, A polypropylene having a cross-linked structure that is cross-linked by introducing a reactive functional group and reacting with each other, and the length of each main chain extending from the cross-linking point is sufficiently long that two polymer molecular chains are mutually linked. The polymer main chain is regulated by making the distance between two molecular chains close and keeping them parallel while making them accessible at a fairly short distance. Any structure may be used as long as it can provide a regular long-distance structure.

What is important in the present invention is that the molecular weight between the cross-linking points of the boiling xylene-soluble part in the crystalline polypropylene having the cross-linking structure thus formed is 1000 to 30.
It has a crosslinked structure in the range of 0000.

In any structure, if the degree of cross-linking is high, the polymer gels. The gelled substance can control the crystallinity, but the final physical properties and easiness of handling should be taken into consideration. For example, it is preferable that the boiling xylene insoluble portion is 10% by weight or less, and in consideration of recyclability and the like, it is more preferable that the boiling xylene insoluble portion is 0.1% by weight or less and is not gelled.

That is, the polypropylene having a molecular weight of less than 1000 between the cross-linking points is not preferable because the flowability is deteriorated and the gel is increased in the polymer. In particular, when the gel content is large, the physical properties are deteriorated, and good molded products cannot be obtained. On the contrary, when the molecular weight between the cross-linking points exceeds 300,000, the effect of improving the physical properties becomes small, which is not preferable.

Such cross-linked polypropylene usually contains a trifunctional or more polyfunctional monomer (vinyl group is counted as bifunctional) having at least two polymerizable unsaturated bonds capable of copolymerizing with propylene. It can be obtained by copolymerization or by reacting polypropylene having reactive functional groups. Alternatively, it can also be synthesized by treating polypropylene with a radical initiator or the like using a low molecular weight compound having two or more functional groups as a crosslinking agent.

The trifunctional or higher polyfunctional monomer having at least two polymerizable unsaturated bonds capable of copolymerizing with propylene may be linear or branched, and may be oxygen, sulfur, boron or the like. And various compounds such as diene and triene which may contain a hetero atom or atomic group. For example, polyfunctional monomers such as 1,3-butadiene, 1,4-pentadiene, 1,5-hexadiene, 1,6-heptadiene, 1,7-octadiene, 1,8-nonadiene, 1,9-decadiene, 1 , 10- Undecadiene, 1,11- Dodecadiene,
Examples include 1,13-tetradecadiene and divinylbenzene.

The content of these polyfunctional monomers in the copolymer is such that the polyfunctional monomer content is in the range of 0.0001 to 5 mol%, more preferably 0.0005 to 3 mol%. is there. In particular, when the content of the polyfunctional monomer is less than 0.0001 mol%, the crystallinity of the polymer is hardly affected, and the object of the present invention cannot be achieved. Further, if the content exceeds 5 mol%, the molecular weight of the copolymer becomes very large, the polymer becomes insoluble in the solvent, and the infusible portion exists even when heated, and the moldability deteriorates. Since the physical properties also deteriorate, the industrial utility value is lost. These copolymers may be random copolymers or block copolymers.

There are no particular restrictions on the catalyst used for polymerization in the production of copolymers of these monomers and polyfunctional monomers, and radical initiators, cationic polymerization initiators and anionic polymerization initiators commonly used in the production of polymers are used. Or, it is generally synthesized using a catalyst composed of a transition metal compound and an organometallic compound. In the case of the above-mentioned polyolefin, titanium halide, an organic compound such as a transition metal compound known as a Ziegler catalyst is used. A solid catalyst made of an organoaluminum compound as a metal compound, or a transition metal catalyst soluble in a hydrocarbon solvent as a ligand, an unsaturated hydrocarbon compound such as a cyclopentadienyl derivative as a ligand Reacting a metallocene compound of Group 5 or 5 with organic aluminum and water or crystal water as necessary A stable anion is formed with an activator comprising an aluminoxane compound which is an oligomer or polymer obtained, or a metal cation complex of Group 3, 4 or 5 of the periodic table having a cyclopentadienyl compound as a ligand. A catalyst or the like in which an activator composed of the compound is combined can be used.

In the method of chemically crosslinking polypropylene by reacting it with a crosslinking agent, or by introducing a reactive functional group into the main chain to cause crosslinking, the functional group to be introduced is not particularly limited, As long as it produces a polypropylene having a crosslinked structure, specifically, an acid anhydride such as maleic anhydride, an epoxy group, a hydroxyl group,
Phenolic hydroxyl group, aldehyde group, mercaptan group, carboxyl group, halogen, amino group, amide group,
Like unsaturated double bonds such as imino groups, vinyl groups and vinylidene groups, or unsaturated triple bonds, reactive functional groups such as carbonyl groups, cyano groups, hydrosilyl groups and alkoxysilyl groups, or acetylacetonate groups Examples thereof include a chelate bond with a metal ion, a chelate-forming group that forms a salt, and a salt-forming group. Cross-linked polypropylene is obtained by reacting polypropylenes having these functional groups. Alternatively, it can be synthesized by using a low molecular weight compound having two or more functional groups as a crosslinking agent.

For example, when polypropylene has a hydroxyl group as a functional group, an aldehyde, an N-methylol compound, a dicarboxylic acid, a dicarboxylic acid chloride, a bishalogen compound, a bisepoxide, a bisaziridine or the like serves as a crosslinking agent. A polymer having a carboxyl group forms a secondary bond due to the interaction thereof, but even when it reacts with a divalent or polyvalent metal oxide or a metal salt of an organic acid, a crosslink of an ionic bond is formed. Further, diamine, diol, bisepoxide, etc. serve as a crosslinking agent. For the imino group and amino group, epichlorohydrin, diisocyanate, and the like serve as crosslinking agents.

Further, the cross-linking point does not necessarily have to be a chemical bond, and a polymer chain portion (soft segment) which is relatively easy to thermally move and a portion having a very strong intermolecular force (hard segment) are mixed. It may be a secondary bond such as the above polymer.

The talc used in the present invention is not particularly limited, and various talcs commonly used for improving the physical properties of known polypropylene can be used. The particle size of talc used is not particularly limited, and the average particle size is 0.1 μ to 50 μ.
The thing of about m is used. Two or more kinds of these talcs can be used in combination.

These talcs may be mixed as they are, or those whose surface is treated with various coupling agents in order to improve the affinity with polypropylene may be used.

In the polypropylene composition of the present invention, the mixing ratio of the crystalline polypropylene (A) and the crystalline polypropylene (B) having a crosslinked structure is 0.01 parts by weight of the component (B) with respect to 100 parts by weight of the component (A). The mixing amount is preferably 0.5 to 30 parts by weight, and a mixing amount of 0.5 to 30 parts by weight is preferable in consideration of the effect of improving physical properties and the cost balance. The mixing ratio of talc (C) is 1 to 90 parts by weight based on 100 parts by weight of the total composition.

The polypropylene composition of the present invention contains additives such as an antioxidant, an ultraviolet absorber, a lubricant, an antistatic agent, a flame retardant, a foaming agent and a nucleating agent which are usually used as stabilizers and modifiers for polypropylene. There is no particular limitation on the addition.

There is no particular limitation on the mixing method of each of these components, and the composition is prepared by mixing with a Henschel mixer, a blender or the like and then melt-mixing with a single-screw extruder, a twin-screw extruder, a roll, a Banbury mixer, a kneader or the like. Can be

[0026]

The present invention will be described in more detail with reference to the following examples.

Example 1 [Synthesis of propylene / diene copolymer] 1 liter of toluene was placed in a stainless steel autoclave having an internal volume of 2 liter, and 0.86 g of methylaluminoxane (manufactured by Tosoh Akzo Co., degree of polymerization 16.2). And 2.4 g of 1,5-hexadiene were charged. Further, a solution prepared by dissolving 3 mg of dimethylsilylbis (2,4-dimethylcyclopentadienyl) zirconium dichloride synthesized according to a conventional method by introducing propylene gas at 20 ° C to 3 kg / cm ² -G in 10 ml of toluene was added. And polymerized at 20 ° C. for 2 hours.

After the completion of the polymerization, unreacted propylene was purged and the polymer was taken out by filtration, vacuum dried at 80 ° C. for 8 hours, and weighed to give 122.3 g of propylene / 1.
A 5-hexadiene copolymer was obtained. The composition of the reaction solution before and after the polymerization was analyzed by gas chromatography to calculate the reaction amount of 1,5-hexadiene, which was 1.25 g. The boiling xylene-soluble content was 99.5% by weight, and no gel was formed.

[0029]¹Signal of terminal vinyl group in 1 H-NMR
Was observed around 6 ppm, and the amount was about 0.2% by weight.
Yes, most double bonds are considered reactive
And propylene / 1,5-hexa with a molecular weight between crosslinking points of 9800
A diene copolymer was obtained. Also ¹³M determined from C-NMR
mmm pentad fraction is 0.98, 135 ℃
Intrinsic viscosity number measured with Larin solution (hereinafter referred to as [η]
Is 1.09, using 1,2,4-trichlorobenzene.
Weight measured by lupe permeation chromatography
Ratio of average molecular weight and number average molecular weight (hereinafter Mw / Mn and
Write down. ) Was 4.6.

[Production of Resin Composition] The above-mentioned propylene /
Diene copolymer, talc and polypropylene (manufactured by Mitsui Toatsu Chemicals, Inc., block copolymer BJHH) were added at the ratio (parts by weight) shown in (Table 1), and 0.1 part by weight of antioxidant was further added. , 0.1 part by weight of calcium stearate and mixed with a Henschel mixer, then 230 with an extruder
The mixture was heated and mixed at ℃ to obtain pellets. Using the pellets, a test piece was molded with an injection molding machine (FSM55T, manufactured by Komatsu Ltd.) and the physical properties were measured. The results are shown in (Table 1). The flexural modulus is ASTM-D790, the tensile strength is ASTM-D638, and the Izod impact strength is AST.
M-D256, Rockwell hardness is ASTM-D785
It was measured according to.

Comparative Example 1 Polypropylene (block copolymer BJH manufactured by Mitsui Toatsu Chemicals, Inc., without adding a propylene / diene copolymer)
Example 1 was repeated except that H) and talc were used. The results are shown in (Table 1).

[0032]

[Table 1] Example 2 Polypropylene grafted with 0.2 mol% of maleic anhydride and polypropylene grafted with 0.2 mol% of N- [4- (2,3-epoxypropyl) -3,5-dimethylbenzyl] methacrylamide. And 50 parts by weight of 2,6-di-tert-butyl-4-methylphenol as a stabilizer.
1 part by weight and 0.1 part by weight of calcium stearate were mixed, mixed with a Henschel mixer, and then heat-mixed with an extruder at 230 ° C. to pelletize to obtain a crosslinked product. The obtained crosslinked product [η] was 1.30 and Mw / Mn was 8.3. The proportion of insoluble matter extracted with boiling xylene for 6 hours was 0.001% by weight, and the molecular weight between crosslinking points was calculated to be 21,000. Using the obtained crosslinked product (copolymer), molded products were obtained in the proportions shown in Table 2 in the same manner as in Example 1. The physical properties of these molded products were measured. The measurement results are shown in (Table 2).

[0033]

[Table 2] Example 3 [Synthesis of catalyst] A vibration mill equipped with four grinding pots having an inner volume of 4 liters and containing 9 kg of steel balls having a diameter of 12 mm is prepared. In each pot under a nitrogen atmosphere, 300 g of magnesium chloride, 60 ml of tetraethoxysilane and α,
45 ml of α, α-trichlorotoluene was added and crushed for 40 hours. The co-ground product 3000 thus obtained was placed in a 5-liter flask, 1.5 liters of titanium tetrachloride and 1.5 liters of toluene were added, and the mixture was stirred at 100 ° C. for 30 minutes, and then the supernatant was removed. Again add 1.5 liters of titanium tetrachloride and 1.5 liters of toluene,
The mixture was stirred at 100 ° C. for 30 minutes, and the supernatant was removed.
Then, the solid content was repeatedly washed with n-hexane to obtain a transition metal catalyst slurry. As a result of sampling a part and analyzing the titanium content, the titanium content was 1.9% by weight.

[Production of silylethylene / propylene copolymer] 800 ml of toluene, 2 g of the above transition metal catalyst, 2.56 ml of diethylaluminum chloride, 1.2 ml of methyl p-toluate and triethyl were placed in an autoclave having an internal volume of 100 liters under a nitrogen atmosphere. Aluminum 4
Add 30 ml of propylene and 20 of silylethylene.
After adding 0 g and pressurizing hydrogen concentration equivalent to 7.5%,
Polymerization was carried out at 0 ° C for 2 hours. After the polymerization, unreacted propylene was purged, the powder was taken out, and dried to obtain 9.6 kg of powder.

[Η] was measured and measured with a differential thermal analyzer.
When the melting point and the crystallization temperature were measured as the maximum peak temperature by raising or lowering the temperature at ℃ / min, the obtained powder had [η] of 0.89, and the melting point was 160 ° C and the crystallization temperature was 120 ° C. Was a crystalline propylene copolymer. According to elemental analysis, the content of silylethylene unit was 0.068 mol%.

[Crosslinking Reaction with Maleic Anhydride] 0.1 part by weight of 2,6-di-tert-butyl-4-methylphenol as a stabilizer based on 100 parts by weight of the obtained crystalline propylene copolymer. , 0.1 part by weight of calcium stearate,
Tetrakis [2- (3,5-di-tert-butyl-4-hydroxyphenyl) ethylcarbonyloxymethyl] methane 0.05
Parts by weight, 0.1 part by weight of maleic anhydride, and a Henschel mixer, and then 220 ° C.
Then, the mixture was heated and mixed in an extruder and pelletized to obtain a crosslinked product.
The obtained crosslinked product [η] was 1.28, and Mw / Mn
Was 7.2. The proportion of insoluble matter when extracted with boiling xylene for 6 hours was 0.001% by weight. The concentration of reacted silyl groups was determined from the infrared absorption spectrum, and the molecular weight between crosslinking points was determined to be about 62,000.

These crosslinked products were talc, EPR (manufactured by Nippon Synthetic Rubber Co., Ltd., EP-01P) and polypropylene (manufactured by Mitsui Toatsu Chemicals, Inc., block copolymer BJH).
H) was molded at the ratio shown in (Table 3) in the same manner as in Example 1, and the physical properties of the molded product were measured. The measurement results are shown in (Table 3).

Comparative Example 2 Polypropylene (manufactured by Mitsui Toatsu Chemicals, Inc., block copolymer BJHH), talc, and EPR (Nippon Synthetic Rubber Co., Ltd.) without adding a silylethylene / propylene copolymer.
The same procedure as in Example 3 was performed except that only EP-01P manufactured by the company was used. The results are shown in (Table 3).

[0039]

[Table 3] Example 4 [Production of silylethylene / propylene copolymer] In Example 3, 8 g of a transition metal catalyst and 950 g of silylethylene.
Was added, and 4.9 kg of powder was obtained in the same manner as in Example 3 except that hydrogen concentration equivalent to 5% was injected under pressure. The melting point and crystallization temperature were measured as the maximum peak temperature by raising or lowering the obtained powder at 10 ° C./min using a differential thermal analyzer, and the obtained powder was [η] 1.
It was 22 and was a crystalline propylene copolymer having a melting point of 160 ° C and a crystallization temperature of 120 ° C. According to elemental analysis, the content of silylethylene unit was 0.56 mol%.

[Crosslinking with rhodium chloride triphenylphosphine complex] To 1 kg of the silylethylene / propylene copolymer obtained above, 1 g of an antioxidant, 1 g of calcium stearate and 20 mg of a triphenylphosphine complex of rhodium chloride. Was added and mixed by a Henschel mixer, and then heat-mixed by an extruder at 230 ° C. and pelletized to obtain a crosslinked product. The obtained crosslinked product [η] was 1.22, and the proportion of insoluble matter when extracted with boiling xylene for 6 hours was 0.001% by weight. The concentration of reacted silyl groups was determined from the infrared spectrum, and the molecular weight between crosslinking points was calculated to be 84,000.

The cross-linked product obtained in this manner was used (Table 4)
The physical properties of the molded product molded in the same manner as in Example 1 at the ratio shown in Table 1 were measured. The measurement results are shown in (Table 4).

[0042]

[Table 4]

[0043]

INDUSTRIAL APPLICABILITY The polypropylene composition of the present invention makes it possible to obtain a molded article having excellent balance of rigidity and impact resistance and heat resistance, and is industrially extremely valuable.

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[Procedure amendment]

[Submission date] August 18, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction content]

Crystalline polypropylene used in the present invention
(A) is not particularly limited as long as it is a polypropylene having crystallinity, and examples thereof include not only a propylene homopolymer but also a copolymer of propylene and two or more other olefins having 2 to 20 carbon atoms. . Random copolymers with other olefins or block copolymers are also included. For example, a binary or ternary copolymer of propylene and an olefin such as ethylene, butene, pentene, hexene, cyclopentene, cyclohexene, 3methylpentene, and 4methylpentene may be used. In addition, polypropylene and poly-α-olefins such as polybutene, polypentene, polyhexene, polyheptene, and polyoctene; cyclic polyolefins such as polycyclopentene and polynorbornene; or composites of propylene / ethylene rubber (EPR) and propylene / ethylene / diene rubber. Can also be used. In these copolymers, the proportion of components other than propylene used is 10 in random copolymerization.
In the case of block copolymerization, it is preferably less than 50% by weight, and 50% by weight or more of the total amount of propylene alone is polymerized.
Further, in the composite, the proportion of components other than polypropylene used is preferably less than 50% by weight.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] 0032

[Correction method] Change

[Correction content]

[0032]

[Table 1] Example 2 Polypropylene grafted with 0.2 mol% of maleic anhydride and polypropylene grafted with 0.2 mol% of N- [4- (2,3-epoxypropyl) -3,5-dimethylbenzyl] methacrylamide. And 50 parts by weight of 2,6-di-tert-butyl-4-methylphenol as a stabilizer.
1 part by weight and 0.1 part by weight of calcium stearate were mixed, mixed with a Henschel mixer, and then heat-mixed with an extruder at 230 ° C. to pelletize to obtain a crosslinked product. The obtained crosslinked product [η] was 1.30 and Mw / Mn was 8.3. The proportion of insoluble matter extracted with boiling xylene for 6 hours was 0.001% by weight, and the molecular weight between crosslinking points was calculated to be 21,000. Using the obtained crosslinked product (copolymer), molded products were obtained in the proportions shown in Table 2 in the same manner as in Example 1. The physical properties of these molded products were measured. The measurement results are shown in (Table 2).

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0033

[Correction method] Change

[Correction content]

[0033]

[Table 2] Example 3 [Synthesis of catalyst] A vibration mill equipped with four grinding pots having an inner volume of 4 liters and containing 9 kg of steel balls having a diameter of 12 mm is prepared. In each pot under a nitrogen atmosphere, 300 g of magnesium chloride, 60 ml of tetraethoxysilane and α,
45 ml of α, α-trichlorotoluene was added and crushed for 40 hours. The co-ground product 3000 thus obtained was placed in a 5-liter flask, 1.5 liters of titanium tetrachloride and 1.5 liters of toluene were added, and the mixture was stirred at 100 ° C. for 30 minutes, and then the supernatant was removed. Again add 1.5 liters of titanium tetrachloride and 1.5 liters of toluene,
The mixture was stirred at 100 ° C. for 30 minutes, and the supernatant was removed.
Then, the solid content was repeatedly washed with n-hexane to obtain a transition metal catalyst slurry. As a result of sampling a part and analyzing the titanium content, the titanium content was 1.9% by weight.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0039

[Correction method] Change

[Correction content]

[0039]

[Table 3] Example 4 [Production of silylethylene / propylene copolymer] In Example 3, 8 g of a transition metal catalyst and 950 g of silylethylene.
Was added, and 4.9 kg of powder was obtained in the same manner as in Example 3 except that hydrogen concentration equivalent to 5% was injected under pressure. The melting point and crystallization temperature were measured as the maximum peak temperature by raising or lowering the obtained powder at 10 ° C./min using a differential thermal analyzer, and the obtained powder was [η] 1.
It was 22 and was a crystalline propylene copolymer having a melting point of 160 ° C and a crystallization temperature of 120 ° C. According to elemental analysis, the content of silylethylene unit was 0.56 mol%.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0042

[Correction method] Change

[Correction content]

[0042]

[Table 4]

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kaoru Kawanishi, 6-6 Takasago, Takaishi-shi, Osaka Mitsui Toatsu Chemical Co., Ltd.

Claims (1)

[Claims] 1. A crystal having a crosslinked structure in which (A) crystalline polypropylene and (B) boiling xylene insoluble portion is 10% by weight or less, and the molecular weight between the crosslinking points of the boiling xylene soluble portion is in the range of 1,000 to 300,000. A polypropylene resin composition composed of a transparent polypropylene and (C) talc.