Asahi Kasei Kogyo Kabushiki Kaisha

Asahi Kasei Kabushiki Kaisha

Asahi Kasei Kogyo Kabushiki

Mitsuhiro Tanaka

Tetsuo Masubuchi

Yasuo Hattori

Takeshi Ikematsu

Yoshihiro Inoki

An elastomer composition which comprises: (a) 100 parts by weight of a hydrogenated block copolymer prepared by hydrogenating a block copolymer that comprises: a polymer block A mainly comprising at least one vinyl aromatic compound; and a polymer block B mainly comprising at least one conjugate diene, and has a number average molecular weight of from 30,000 to 400,000 and a content of the polymer block A of from 10 to 50% by weight based on the weight of said block copolymer; (b) 5 to 900 parts by weight of a polypropylene mixture comprising: (b-1) 10 to 60% by weight of a polypropylene polymer having a propylene content of 85% by weight or more; and (b-2) 40 to 90% by weight of an ethylene-propylene copolymer rubber having a propylene content of 75% by weight or more, wherein the ethylene-propylene copolymer rubber in said mixture has an average dispersed particle size of not more than 2 &mgr;m and said mixture has a bending modulus of from 20 to 700 Mpa, a Shore D hardness of from 20 to 60 and a melt flow rate of from 10 to 60 g/10 minutes; and (c) 0 to 200 parts by weight of a hydrocarbon oil. Also disclosed is a housing cover of air bag apparatus, which comprises the elastomer composition.

Elastomer composition

An elastomer composition which comprises (a) 100 parts by weight of a hydrogenated block copolymer mixture comprising: (a-1) 10 to 60 parts by weight of a block copolymer prepared by hydrogenating a block copolymer that comprises: at least two polymer blocks A each mainly comprising a vinyl aromatic compound; and at least one polymer block B mainly comprising a conjugated diene compound, the hydrogenated block copolymer having a number average molecular weight of from more than 200,000 to not more than 400,000 and a content of the polymer block A of from 15 to 40% by weight of said block copolymer; and (a-2) 40 to 90 parts by weight of a block copolymer prepared by hydrogenating a block copolymer that comprises: at least one polymer block A mainly comprising a vinyl aromatic compound; and at least one polymer block B mainly comprising a conjugated diene compound, the hydrogenating block copolymer having a number average molecular weight of from more than 30,000 to not more than 140,000 and a content of the polymer block A of from 8 to 35% by weight of said block copolymer; and (b) 30 to 125 parts by weight of a polypropylene resin having a melt flow rate of from 5 to 100 g/10 minutes; (c) 0 to 50 parts by weight of a hydrocarbon oil. Also disclosed is a housing cover of air bag apparatus, which comprises the elastomer composition.

Air bag cover containing a block copolymer polypropylene resin blend

Air bag cover from hydrogenated block copolymer mixture and polyolefin

A butadiene polymer or a copolymer of butadiene with another conjugated diene having the following structural parameters and physical properties:

Crystalline trans-butadiene polymers

Growing community of inventors

Yokohama, Japan

Mitsuhiro Tanaka