Catalyst systems for Ziegler-Natta propene polymerisation

摘要

The invention relates to the use of nitrogenous aluminium organyl complexes of general formula (I) as co-catalysts in heterogeneous polymerisation reactions of propene. In said formula: R, R', R¹ and R¹' independently of one another represent branched or unbranched C₁-C₇ alkyl, cycloalkyl, alkenyl, cycloalkenyl, aryl or alkynyl; R² represents unsubstituted, monoalkylated or polyalkylated and/or monofluorinated or polyfluorinated aromatic hydrocarbons from group (II); R³ and R⁴ independently of one another represent CH₂, CF₂ oder C(R¹)₂; m stands for 0, 1 or 2; n stands for 0, 1 or 2; o stands for 0 or 1, all independently of one another. Said systems exhibit improved characteristics in terms of activity and stereoselectivity in comparison to conventional co-catalysts such as AlEt₃ and can act simultaneously as co-catalysts and stereoselectivity promoters