Patent ID: 8779058

Claim:
A polymerization process comprising: contacting propylene and optionally at least one other olefin with a catalyst composition in a first polymerization reactor under gas phase polymerization conditions, the catalyst composition comprising a procatalyst having a diether internal electron donor which is 9,9-bis(methoxymethyl)-9H-fluorene, a cocatalyst and a mixed external electron donor (M-EED) comprising a first selectivity control agent (SCA1) which is dicyclopentyldimethoxysilane and an activity limiting agent (ALA) which is isopropyl myristate; forming, in the first polymerization reactor, an active propylene-based polymer having a melt flow rate greater than 100 g/10 min as measured in accordance with ASTM D1238-01 (230° C., 2.16 kg); contacting the active propylene-based polymer with at least one olefin in a second reactor under polymerization conditions; and forming a propylene impact copolymer having a melt flow rate greater than 60 g/10 min and an Izod impact strength of 9.85 kJ/m 2 .