Hydrogen transfer reactions of supported metallocene catalysts

被引：63

作者：

Kaminsky, W ^{[1
]}

Strubel, C ^{[1
]}

机构：

[1] Univ Hamburg, Inst Tech & Makromol Chem, D-21046 Hamburg, Germany

来源：

JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL | 1998年 / 128卷 / 1-3期

关键词：

supported metallocenes; hydrogen transfer; deactivation; methane evolution; olefin polymerization; leaching;

D O I：

10.1016/S1381-1169(97)00172-6

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：

The evolution of methane from methylaluminoxane (MAO) solutions is enhanced in the presence of homogeneous metallocenes. This reaction serves as a model for the deactivation of metallocene catalysts. By supporting different metallocenes on a silica/MAO carrier the deactivation reaction by alpha-hydrogen transfer among metallocene active sites and aluminum alkyls can be suppressed. The suppression of alpha-hydrogen transfer is proven for different Al/Zr ratios and by near independence of the polymerization activity on the catalyst aging time, after reaching maximum activity. Aluminum alkyls and MAO leach Cp2ZrCl2 from the carrier, the leached metallocene is only active in polymerization if MAO is present. (C) 1998 Elsevier Science B.V.

引用

页码：191 / 200

页数：10

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