Patent ID: 8148482
Filing Date: 2012-04-03
Classification: B01J,C08F

Abstract:
1. A process for forming a multi-block copolymer, said copolymer containing therein two or more chemically distinguishable segments or blocks, at least one of which comprises a tactic polymer, the process comprising polymerizing one or more olefin monomers, at least one of which is capable of forming a tactic polymer, in the presence of a chain shuttling agent and a catalyst composition comprising: two or more olefin polymerization catalysts capable of preparing polymers having differing chemical or physical properties under equivalent polymerization conditions, or at least one olefin polymerization catalyst containing multiple active catalyst sites capable of preparing polymers having differing chemical or physical properties; characterized in that at least one of the olefin polymerization catalysts comprises a metal complex containing at least one asymmetrically substituted (chiral) carbon atom, said metal complex being present in the form of a non-racemic mixture of the R- and S- enantiomers thereof.