| abstract |
Catalyst systems of the Ziegler-Natta type, containing active ingredients a) a titanium-containing solid component, the titanium, magnesium, halogen and a norbornadienedicarboxylic acid ester of the general formula I. contains as electron donor in which R¹ and R² are C₁-C₈-alkyl groups or 5- to 7-membered cycloalkyl groups, which in turn may be C₁-C₁₀-alkyl groups, b) an aluminum component and c) another electron donor component.n n n These catalyst systems are particularly suitable for the production of polypropylene and copolymers of propylene with minor amounts of other α, β-unsaturated olefinic compounds having 2 to 8 carbon atoms. |