Unbridged metallocene dichloride complexes with mono-substituted indenyl ligands and their application for the polymerization of propene

The synthesis of unbridged metallocene dichloride complexes of the type Ind 2'ZrCl2 (Ind' = 2-alkyl- or arylalkyl-substituted indenyl) is described. Th e complexes are characterized by H-1- and C-13-NMR spectroscopy and mass sp ectrometry. After activation with methylalumoxane these complexes can be us ed for propene polymerization; they produce block copolymers consisting of alternating isotactic and atactic blocks. The polymerization results and th e polymer properties are presented. The influence of the catalyst structure on the polymerization behaviour is discussed. (C) 2001 Elsevier Science B. V. All rights reserved.