Propylene polymer composition useful for bumpers

Abstract

A bumper having excellent rigidity, resistance to thermal deformation and to mechanical impact at a low temperature and superior lacquer-bonding property is made from a propylene polymer composition comprising: (A) 55 to 65% by weight of at least one crystalline ethylene-propylene block copolymer in which the content of the polymerized ethylene is in the range of from 5 to 10% by weight, in which the polypropylene component has a fraction thereof insoluble in boiling n-heptane, in an amount of 97% or more, in which a fraction thereof soluble in p-xylene at room temperature, has an intrinsic viscosity of from 3 to 4 determined in decahydronaphthalene at a temperature of 135.degree. C. and which has a melt flow index of from 2 to 10; (B) 30 to 35% by weight of at least one amorphous ethylene-propylene copolymer having an intrinsic viscosity of from 2.0 to 3.5 determined in decahydronaphthalene at a temperature of 135.degree. C., and a Mooney viscosity ML.sub.1+4 of from 40 to 100 determined at a temperature of 100.degree. C., and; (C) 5 to 15% by weight of talc in the form of fine particles having an average size of from 0.5 to 5 microns.

Dependencies are inferred from the claim text.