摘要 |
CATALYST COMPOSITION COMPRISING SHUTTLING AGENT FOR HIGHER OLEFIN MULTI-BLOCK COPOLYMER FORMATION Copolymers, especially multi-block copolymer containing therein two or more segments or blocks differing in chemical or physical properties, are prepared by polymerizing propylene, 4-methyl- I-pentene, or other C4-8 &agr;-olefin and one or more copolymerizable comonomers, especially ethylene in the presence of a composition comprising the admixture or reaction product resulting from combining: (A) a first metal complex olefin polymerization catalyst, (B) a second metal complex olefin polymerization catalyst capable of preparing polymers differing in chemical or physical properties from the polymer prepared by catalyst (A) under equivalent polymerization conditions, and (C) a chain shuttling agent. |