Sumitomo Chemical Company, Limited

Jiro Mori

Kazuki Wakamatsu

Hajime Sadatoshi

Seiichiro Ima

Eisuke Shiratani

Yasunori Kaminaga

Tomoaki Tanaka

A process (I) for producing an &agr;-olefin polymerization catalyst whereby (1) a titanium compound is reduced by an organomagnesium compound in the presence of an organosilicon compound to produce a reduction solid, (2) the reduction solid is aged to produce a solid product, (3) the solid product is contacted with an ether compound, titanium tetrachloride and an organic acid halide compound, to produce an organic acid halide-treated solid, (4) the organic acid halide-treated solid is contacted with a mixture of an ether compound, titanium tetrachloride and an ester compound, or with a mixture of an ether compound and titanium tetrachloride to produce a solid catalyst component containing a titanium compound, and (5) the solid catalyst component is contacted with an aluminum compound and an electron donor compound to produce a catalyst for &agr;-olefin polymerization. A process (II) for producing an &agr;-olefin polymer using a catalyst produced by process (I).

Process for producing catalyst for &agr;-olefin polymerization, and process for producing &agr;-olefin polymer

Polypropylene random copolymer and film thereof

A polypropylene composition comprising a melt-kneaded polyprolylene composition obtained, using Zieglar-Natta catalyst, by polymerizing a monomer comprising propylene to form a polymer comprising polypropylene (component A) in amount of from 60 to 80% by weight to the total polymer amount in substantially the absence of an inert solvent in a 1st step and then polymerizing a mixture of ethylene content of from 20 to 50% by weight (component B) in a vapor phase to form an ethylene-propylene copolymer (component B) in amount of from 20 to 40% by weight to the total polymer amount in a 2nd step, said polypropylene composition being such that the intrinsic viscosity of component B ([.eta.]B) is at least 2.0 dl/g and the ratio ([.eta.]B/[.eta.]A) of the intrinsic viscosity of the component B to the intrinsic viscosity of the component A ([.eta.]A) is 1.8 or less and the melt flow rate of the polypropylene composition after melt-kneaded being 0.5 to 10 g/10 minutes.

Polypropylene composition and the film thereof

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Sodegaura, Japan

Jiro Mori