Patent ID: 8044135

Claim:
An impact-resistant olefin polymer composition comprising: (a) a propylene based matrix having a weight average molecular weight and (b) an ethylene-containing polymer including an ethylene-propylene rubber copolymer having a molecular weight higher than the weight average molecular weight of the propylene based matrix, said composition containing about 20 to 35 percent xylene solubles, wherein about 96-98 percent isotactic pentads (mmmm) of xylene insolubles are present in the propylene based matrix, said xylene solubles fraction contains from about 25 to about 39 weight percent ethylene units, based on the combined weight of olefin monomers in said copolymer, the ratio of weight average molecular weight of xylene solubles to weight average molecular weight of xylene insolubles of the composition is about 1.05 to about 1.5 and said composition has a melt flow rate greater than about 8.5 g/10 minutes.