Crystalline ethylene-propylene copolymer with ethylene copolymer(s) and/or alkenyl aromatic-grafted rubber

摘要

A thermoplastic resin composition which has a melt flow rate of 25 to 30 g/10 min and a flexural modulus at 23° C. of 20,000 kg/cm. sup. 2 or more and which comprises (1) 78 to 87% by weight of a specific crystalline polypropylene [referred to hereinafter as (A)] in which the propylene homopolymer portion has a Q value of 3.0 to 5.0, an isotactic pentad fraction of 0.975 or more and an intrinsic viscosity [&eegr;] of 1. 00 to 1.10 dl/g as measured at 135° C. in tetralin, (2) 3 to 10% by weight of at least two specific rubber components selected from the group consisting of (B) 1 to 9% by weight of an ethylene-butene-1 copolymer rubber, (C) 1 to 9% by weight of an ethylene-propylene copolymer rubber and (D) 1 to 9% by weight of an alkenyl aromatic compound-containing rubber; and (3) 10 to 12% by weight of talc having an average particle diameter of 4 &mgr;m or less, and an injection molded article of the thermoplastic resin composition, said thermoplastic resin composition satisfying the impact strength and rigidity required as a material for an interior automotive trim and having a short molding cycle and good surface quality.