Patent ID: 6803418
Filing Date: 2004-10-12
Classification: C08L

Abstract:
An olefinic thermoplastic elastomer composition produced by a process comprising the step of dynamically heat treating 5 to 50 parts by weight of a polypropylene resin (A) and 50 to 95 parts by weight of an &agr;-olefinic copolymer (B) having a Mooney viscosity ML1+4 (100Â° C.) of 60 to 250 [the total amount of (A) and (B) being 100 parts by weight] in the absence of a crosslinking agent,wherein the glass transition temperature (Tg) in dynamic visco-elasticity measurement derived from the polypropylene resin (A) in the elastomer composition is lower than the glass transition temperature (Tg) of the polypropylene resin (A) alone, and wherein the &agr;-olefinic copolymer (B) is at least one of &agr;-olefinic copolymers selected from the following (b-1) and (b-2): (b-1) ethylene-&agr;-olefinic copolymers which have an ethylene content of 51 to 60 mol % to the total amount of the propylene-&agr;-olefinic copolymer-constituting ethylene and &agr;-olefin other than ethylene, (b-2) propylene-&agr;-olefinic copolymers which have a propylene content of 60 to 90 mol % to the total amount of the ethylene-&agr;-olefinic copolymer-constituting propylene and &agr;-olefin other than propylene.