Patent ID: 6350830
Filing Date: 2002-02-26
Classification: C08F

Abstract:
A catalyst system comprising:a) at least one support, b) at least one cocatalyst, c) an rac/meso isomer mixture of at least one metallocene of the formula (I): â€ƒwhere R1 and R2 are identical or different and are each a hydrogen atom or a C1-C20-hydrocarbon group, with the restriction that R1 is not methyl when R2is hydrogen, M1 is a transition metal of group 4, 5 or 6 of the Periodic Table of the Elements, A is a bridge of the formula: â€ƒor &boxH;BR3, AIR3, â€”Sâ€”, â€”SOâ€”, â€”SO2â€”, &boxH;NR3, &boxH;PR3, &boxH;P(O)R3, o-phenylene, 2,2â€²-biphenylene, where M2 is carbon, silicon, germanium, tin, nitrogen or phosphorus, o is 1, 2, 3 or 4, R3 and R4 are identical or different and are each, independently of one another, a hydrogen atom, halogen, a C1-C20-group or R3 and R4 can together form a monocyclic or polycyclic ring system, and X are identical or different and are each a hydrogen atom, a halogen atom, a hydroxyl group, a C1-C10-alkyl group, a C6-C15-aryl group, a C1-C10-alkoxy group, a C6-C15-aryloxy group, a benzyl group, an NR52 group, where R5 are identical or different and are each a C1-C10-alkyl group, C6-C15-aryl group, a (CH3)3Si group, where the ratio of rac isomer to meso isomer of the metallocene of the formula (I) in the catalyst system of the invention is from 1:10 to 2:1 and wherein the cocatalyst used is an aluminoxane or a Lewis acid or an ionic compound which reacts with a metallocene to convert the latter into a cationic compound.