Self-extinguishing catalyst composition with monocarboxylic acid ester internal door and propylene polymerization process

摘要

A catalyst composition for the polymerization of propylene comprising one or more Ziegler-Natta procatalyst compositions comprising one or more transition metal compounds and one or more monoesters of aromatic carboxylic acid internal electron donors; one or more aluminum containing cocatalysts; and a mixture of two or more different selectivity control agents, said SCA mixture comprising from 98.0 to 99.9 mol percent of one or more esters of one or more aromatic monocarboxylic acids or substituted derivatives thereof, and from 2.0 to 0.1 mol percent of one or more alkoxysilane compounds.