New zirconocenes with 4,5,6,7-tetrahydroindene ligands. Synthesis and catalytic activity in the polymerization of ethylene and copolymerization of ethylene with hex-1-ene

Abstract

A series of symmetric and nonsymmetric tetrahydroindenyl zirconium complexes was obtained by the reaction of ZrCl₄ or (CpTMS)ZrCl₃ with lithium salts of the corresponding tetrahydroindenes. Activated with methylalumoxane, these complexes exhibit high activity in polymerization of ethylene (up to 6.8∙10⁶ g PE (mol Zr h)^–1), as well as in copolymerization of ethylene and hex-1-ene (up to 8.6∙10⁶ g PE (mol Zr h)^–1).