Patent ID: 8138286

Claim:
A process for the preparation of cycloolefin copolymers by polymerization of a) at least one cycloolefin of the general formula (I) in which n is 0 or 1, m is 0 or a positive integer, R 1 , R 2 , R 3 , R 4 , R 5 , R 6 independently of one another, are selected from the group consisting of hydrogen, halogen, cyclic and acyclic branched and straight-chain aliphatic hydrocarbon groups, aromatic hydrocarbon groups and alkoxy groups, R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 , R 16 , independently of one another, are selected from the group consisting of hydrogen and aliphatic hydrocarbon groups, R 17 , R 18 , R 19 , R 20 , independently of one another, are selected from the group consisting of hydrogen, halogens and aliphatic hydrocarbon groups, it also being possible for R 17 and R 19 to be bonded to one another in such a way that they form a single ring or a ring system comprising a plurality of rings, it being possible for the ring or the rings to be saturated or unsaturated, with b) at least one 1-olefin of the formula (II) in which R 21 and R 22 , independently of one another, are selected from the group consisting of hydrogen and C 1-20 -alkyl groups, for the preparation of cycloolefin copolymers, the cycloolefin and the comonomer being polymerized in the presence of a catalyst system which contains metallocene compounds of the general formula (IV) in which M is a metal of group IIIb, IVb, Vb and VIb of the Periodic Table of the Elements, R 313 and R 313a , independently of one another, are selected from the group consisting of hydrogen, C 1-4 -alkyl groups, and aryl, R 311 is selected from the group consisting of isopropanyl and phenyl, and R 312 is selected from the group consisting of hydrogen and C 1 -C 4 -alkyl, and the radicals R 311 , R 312 , R 313 and R 313a being selected so that the metallocene compound has no C s symmetry in relation to the centroid-M-centroid plane and wherein the metallocene is utilized in solution.