Noncoordinating anions for olefin polymerization

摘要

Bulky noncoordinating anions that are surprisingly stable under olefin polymerization conditions such that olefin polymers can be prepared with unexpectedly high molecular weights at high catalyst efficiencies. Thus the invention is directed to an olefin polymerization process comprising contacting under polymerization conditions one or more ethylenically unsaturated monomers with a catalyst composition comprising at least one organometallic transition metal compound activated to a cationic state and a stabilizing, compatible non-coordinating Group 13 anionic complex having halogenated aromatic ligands in an essentially tetrahedral structure wherein the aromatic groups are polycyclic fused or pendant aromatic rings.