HIGHLY ISOTACTIC POLYPROPENE PREPARED WITH RAC-DIMETHYLSILYL-BIS(2-METHYL-4-T-BUTYL-CYCLOPENTADIENYL)ZIRCONIUMDICHLORIDE - AN NMR INVESTIGATION OF THE POLYMER MICROSTRUCTURE

被引：63

作者：

RIEGER, B ^{[1
]}

REINMUTH, A ^{[1
]}

ROLL, W ^{[1
]}

BRINTZINGER, HH ^{[1
]}

机构：

[1] UNIV CONSTANCE,FAK CHEM,W-7750 CONSTANCE,GERMANY

来源：

JOURNAL OF MOLECULAR CATALYSIS | 1993年 / 82卷 / 01期

关键词：

CHIRAL ZIRCONOCENES; ISOTACTIC POLYPROPENE; STEREOSPECIFIC OLEFIN POLYMERIZATION;

D O I：

10.1016/0304-5102(93)80071-2

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Isotactic polypropene was prepared using rac-dimethyl-silylbis(2-methyl-4-t-butyl-cyclopentadienyl)zirconiumdichloride (1) and methylalumoxane (MAO) at temperatures between 0 and 80-degrees-C and with Al/Zr ratios of 300 and 1500. The polymers, prepared at temperatures below 30-degrees-C had melting points of 162-degrees-C and above. The chain ends were determined by means of distortionless enhancement by polarization transfer (DEPT)-NMR spectroscopy. The pentad intensities were corrected according to the chemical shifts of the end groups. The intensity distributions are shown to arise from enantiomorphic site control of the chiral catalyst species.

引用

页码：67 / 73

页数：7

共 13 条

[1]

CHENG HN, 1989, MAKROMOL CHEM, V190, P1931

[2]

CHIEN JCW, 1990, CATALYTIC OLEFIN POL, P535

[3] MECHANISMS OF STEREOCHEMICAL CONTROL IN PROPYLENE POLYMERIZATIONS WITH SOLUBLE GROUP-4B METALLOCENE METHYLALUMOXANE CATALYSTS [J].