SELF-LIMITING CATALYST SYSTEM WITH CONTROLLED ALUMINIUM TO SCA RATIO AND METHOD

摘要

FIELD: chemistry.SUBSTANCE: catalyst composition contains: one or more Ziegler-Natta procatalyst compositions having one or more transition metal compounds and one or more internal electron donors in form of esters of aromatic dicarboxylic acid, one or more aluminium-containing cocatalysts and a selectivity control agent (SCA) which contains a mixture of (i) a first alkoxy silane and a second alkoxy silane and (ii) an ester of C-C-aliphatic acid, and the molar ratio of aluminium to total SCA ranges from 0.5:1 to 4:1.EFFECT: catalyst composition improves polymerisation productivity and polymer production rate, the composition is self-extinguishing.9 cl, 15 tbl, 10 dwg