Ziegler-natta catalyst systems containing specific organosilicon compounds

摘要

Catalyst systems of the Ziegler-Natta type contain, as active components a) a titanium-containing solid component in whose preparation a titanium compound, a compound of magnesium, a halogenating agent and an electron donor component are used, b) an aluminum compound and c) as a further electron donor component, an organosilicon compound of the formula (I) R1R2Si(OR3)2(I)where R1 is C1-C10-alkyl or C3-C8-cycloalkyl, excluding sec-butyl, R2 is sec-butyl and R3 is C1-C8-alkyl. The catalyst systems are particularly suitable for the preparation of polymers of C2-C10-alk-1-enes.