RESIN COMPOSITION FOR AUTOMOTIVE BUMPER AND AUTOMOTIVE BUMPER OBTAINED THEREFROM

摘要

PROBLEM TO BE SOLVED: To provide a resin composition which can give an automotive bumper excellent in rigidity and low-temperature impact resistance by mixing a specified propylene/ethylene block copolymer with a specified ethylene/propylene copolymer rubber with specified talc. SOLUTION: This resin composition comprises a propylene/ethylene block copolymer (A) comprising a homopolypropylene part having an isopentad fraction of 0.95 or above and an intrinsic viscosity of 0.6-1.2dl/g and a propylene/ ethylene copolymer part having a propylene/ethylene weight ratio of 75/25 to 25/75 and an intrinsic viscosity of 3.0-11.0dl/g, a propylene homopolymer (B) having an isotactic pentad fraction of 0.95 or above and an intrinsic viscosity of 1.3-4.0dl/g, ethylene/propylene copolymer rubber (C) having a Mooney viscosity of 20-120 and a propylene content of 15-60wt.%, and talc (D) of a mean particle diameter of 0.5-5μm. The composition satisfies the formulas when the amount of the copolymer part of component A isαpts.wt. ((A)+(B)=100).