Process for preparing a block copolymer of ethylene-propylene impact resistant.

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 3 : 2 and 4 : 1, that contains a total amount of 14-20 % (wt) ethylene groups, that has an Izod value measured according to ISO-R-180 at 296 K of at least 30 kJ/m2, that has an E-modulus measured according to ASTM-D-790 at 296 K of at least 900 N/mm2 and that has a melt index measured according to ASTM-D-1238 at 503 K and 21.6 N of 4-20 dg/min and to a process for preparing such an impact-resistant ethylene-propylene block polymer.