SELF-LIMITING CATALYST SYSTEM WITH CONTROLLED ALUMINIUM TO SCA RATIO AND METHOD Russian patent published in 2012 - IPC C08F4/646 C08F4/649 C08F4/651 C08F10/06 

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 C₄-C₃₀-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