Novel Copolymer of Ethylene and Styrene Produced by Bridged Metallocene Catalysts

摘要

Recently, there have been reported the ethylene-styrene (E-S) copolymerizationusing r so-called single-site polymerization catalysts. CGCT catalyst produces "pseudo-random" E-S copolymer1 and Ewen-type Zr complex2 andMe4OpTiBz3-B(C6F5)3*give..the same type of copolymers. However, these copolymers have no head to tail Styrene-chain and no stereo-regularity of the phenyl group in E-S alternating structure. On the other hand, restricted alternating E-S copolymer is produced by Ti-compKex which has a Thio-bis phenol llgand4.This copolymer consists of only isotactic E-S alternating structure. In this presentation, we report a random E-S copolymer having a highly isotactic E~S alternating structure and head to tail styrene chain produced by... some bridged Zirconocene catalysts.