Impact-resistant ethylene-propylene block copolymer and process for preparing such a block copolymer.

摘要

Present invention pertains to a novel impact-resistant ethylene-propylene block copolymer, that at least consists of an at least almost completely homopolymeric propylene part and a copolymeric ethylene-propylene part, the weight ratio between the at least almost completely homopolymeric propylene part and the copolymeric ethylene-propylene part being between 4 : 1 and 9 : 1, that contains a total amount of 10-15 % (wt) ethylene groups, that has an Izod value measured according to ISO-R-180 at 296 K of at least 30 kJ/m<2>, that has an E-modulus measured according to ASTM-D-790 at 296 K of at least 1000 N/mm<2> and that has a melt index measured according to ASTM-D-1238 at 503 K and 21.6 N of 2.5-20 dg/min and to a process for preparing such an impact-resistant ethylene-propylene block copolymer.