Process for the preparation of syndiotactic polyolefins having a broad molecular weight distribution

摘要

Syndiotactic polyolefins having a molecular weight distribution Mw/Mn of >/=3 and which may be monomodal, bimodal or multimodal are obtained by polymerization or copolymerization of olefins of the formula RCH=CHR, in which a catalyst system comprising an aluminoxane and a transition-metal component (metallocene) is used, the transition-metal component comprising at least 2 metallocenes of the formula (I) which are stereorigid and whose moiety formed by Zr and the substituents R1-R4 has Cs symmetry or slightly distorted Cs symmetry.