JPH0798879B2 - Polypropylene resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a polypropylene resin composition having good physical properties. Specifically, it relates to a polypropylene resin composition containing a specific compound.

[Conventional technology]

Polypropylene is an inexpensive resin that has relatively high heat resistance and rigidity, but since it has a relatively low degree of crystallinity, it can be molded with a normal method and the rigidity of the molded product is poorer than that of the resin body. There was a problem. On the other hand, a method of adding various nucleating agents is known, and among them, a method of adding a specific polymer compound (for example, JP-A-60-1397).
No. 31) is an excellent method in which there is no problem that the additive floats on the surface of the molded product, and the addition of a relatively small amount is effective.

[Problems to be solved by the invention]

Although the method of adding a polymer compound is excellent,
The disclosed polymer compounds are difficult to synthesize and difficult to obtain. Therefore, development of other useful compounds is desired.

[Means for solving problems]

The present inventors have intensively searched for a new compound that improves the crystallinity of polypropylene, found that a specific compound is suitable for the purpose, and completed the present invention.

That is, the present invention is a polypropylene resin composition characterized in that the main chain is silicon and contains an organic polysilane having one or more hydrocarbon residues per silicon atom.

In the present invention, the polypropylene is not only a homopolymer of propylene as long as it is a crystalline polypropylene, but also a random copolymer with other olefins such as ethylene, butene-1, and hexene-1, or a block copolymer. Often, it can be produced by polymerizing propylene using a known Ziegler-Natta catalyst, and is also widely available on the market.

In the present invention, the organic polysilane has a main chain of silicon and has one or more hydrocarbon residues per silicon atom. For example, it can be produced by dechlorination polycondensation of a dihalogenated silane with sodium or the like (for example, RCWest, Comprehensive Organic Che
mstry, Vol.2, Chapter 9.4, P365 ~ 387 (1982), edited b
y G. Willkinson et al., Pergamon Press, New York).
Specifically, polyphenylmethylsilane, polyphenethylmethylsilane, polypropylmethylsilane, polybutylmethylsilane, polyhexylmethylsilane, polydodecylmethylsilane, polycyclohexylmethylsilane,
Examples thereof include polydihexylsilane, polydibutylsilane, and polydipetylsilane.

In the present invention, the method of mixing the polypropylene and the polysilane is not particularly limited, and examples thereof include a method of simply mixing and melting the two and a method of polymerizing polypropylene using a catalyst containing polysilane to disperse polysilane. Here, the ratio of polysilane to polypropylene is 0.00001 to 10% by weight, preferably 0.0001 to 1
% By weight. If it is less than 0.00001% by weight, there is almost no effect of addition, and if it is added in excess of 10% by weight, the effect is not particularly increased.

〔Example〕

 Hereinafter, the present invention will be further described with reference to examples.

Example 1 Autoclave of Example 3 was charged with n-heptane 1, 300 mg of titanium trichloride catalyst (TGY-24) manufactured by Marubeni Solvay Co., Ltd. and 1 ml of diethylaluminum chloride, propylene gas was introduced to make 5 kg / cm ^2, and 0.4 Nl of hydrogen was added. After the addition, heating was performed to bring the internal temperature to 70 ° C. Pressure is 5kg / cm while inserting propylene
Polymerization was carried out for ² hours for 3 hours. Deactivate the catalyst with methanol,
It was washed with water to remove the catalyst residue, filtered and dried to obtain a powder. The powder obtained was 850 g and had an intrinsic viscosity of 1.78.
(Measured with a 135 ° C. tetralin solution), the boiling n-heptane extraction residual rate was 98.2% (extracted for 6 hours using a Kumagawa type extractor).

Methylphenyldichlorosilane and dimethyldichlorosilane were reacted with sodium in toluene to synthesize polysilastyrene (according to the method of the above-mentioned document).

Sheet-forming physical properties were measured by mixing 0.1 part by weight of polysilastyrene with 100 parts by weight of the above polypropylene and performing melt pressing.

Tensile yield strength (ASTM D638-67T) is 365kg / cm ² , flexural modulus (ASTM D790-63) is 21000kg / cm ² , crystallization temperature (measured using DSC at 10 ℃ / min). It was 122.3 ° C.

When addition was measured molded to physical properties without using the Comparative Example 1 polysilastyrene were the same as in Example 1, the tensile yield strength and flexural modulus were respectively ^{330kg / cm 2, 18000kg / cm} 2 . The crystallization temperature was low at 112.5 ° C.

Examples 2 and 3 Examples in which 0.5 parts by weight of polydihexylsilane (Example 2) and polymethylbutylsilane (Example 3) obtained in the same manner as in Example 1 were used with respect to 100 parts by weight of polypropylene, respectively. 1 and was similarly, the tensile yield strength, respectively was ^{355kg / cm 2, 350kg / cm} 2, the flexural modulus 2100
0kg / cm ^2, it was 20500kg / cm ^2. The crystallization temperature is 12
It was 1.4 ° C and 122.3 ° C.

〔The invention's effect〕

The composition of the present invention has excellent physical properties and is extremely valuable industrially.

Claims (1)

[Claims] 1. A polypropylene resin composition having a main chain of silicon and containing an organic polysilane having one or more hydrocarbon residues per silicon atom.