Patent ID: 6015766
Filing Date: 2000-01-18
Classification: B01J,C08F

Abstract:
A catalyst composition for polymerization of alpha-olefins comprising the contact product of a metallocene complex of a transition metal of the formulaCp.sub.x MA.sub.y B.sub.zwherein x is 1 or 2; M is titanium, zirconium or hafnium; Cp is a cyclopentadienyl group, a substituted cyclopentadienyl group, a cyclopentadienyl group that is a part of a bicyclic or a tricyclic moiety or, when x is 2, the two cyclopentadienyl groups are optionally bridged to each other; and each of A and B is selected from the group consisting of a halogen atom, a hydrogen atom, an alkyl group, and combinations thereof; providing that x+y+z is equal to the valence of M; anda cocatalyst, alkylaluminate the general formula [--Al(CH.sub.3)O].sub.p --[Al(OR)O].sub.q --, wherein R is a sterically hindered alkyl group and the q:p ratio varies from 1:10 to 1:0, said sterically hindered alkyl group containing a trisubstituted aliphatic carbon atom, --CR'R""R'"", or a disubstituted aliphatic carbon atom, --CHR'R"", where substituents R', R"" and R'"" are the same or different aliphatic, aromatic or alkylaromatic groups.