BIS(TRIMETHYLSILYL) BENZAMIDINATE ZIRCONIUM DICHLORIDES - ACTIVE CATALYSTS FOR ETHYLENE POLYMERIZATION

被引:111
作者
HERSKOVICSKORINE, D [1 ]
EISEN, MS [1 ]
机构
[1] TECHNION ISRAEL INST TECHNOL, DEPT CHEM, IL-32000 HAIFA, ISRAEL
关键词
ZIRCONIUM; ZIRCONOCENE; ZIEGLER-NATTA POLYMERIZATION; BENZAMINIDATE; CRYSTAL STRUCTURE;
D O I
10.1016/0022-328X(95)05576-B
中图分类号
O61 [无机化学];
学科分类号
070301 ; 081704 ;
摘要
A study was made of the polymerization of ethylene involving the use of a series of [eta(4)-4-RC(6)H(4)C(NSiMe(3))(2)]2ZrCl2 as precatalysts (R=H (1); CH3 (2)). The benzamidinate zirconium dichloride complexes were prepared from ZrCl4 and the corresponding 4-RC(6)H(4)C(NSiMe(3))(2)Li . TMEDA ligand. The structure of complex 1 was determined by a low-temperature X-ray diffraction study. ''Cationic'' ethylene polymerization catalysts were generated from 1 and 2 with methylalumoxane. The polymerization activity and the molecular weights of the polymers are strongly dependent on the catalyst and cocatalyst concentrations. The polymerization activity increases drastically with increase in pressure and temperature and decreases when electron-releasing groups are attached to the aromatic ring.
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页码:307 / 314
页数:8
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