Metallocene catalysts and their use in polymerization processes

Abstract

A process for polymerizing olefin(s) utilizing a cyclic bridged metallocene catalyst system to produce polymers with improved properties is provided. The catalyst system may include a cyclic bridged metallocene, L(R'SiR′)LZrQ, activated by an activator, the activator comprising aluminoxane, a modified aluminoxane, or a mixture thereof, and supported by a support, where: Land Lare independently an unsubstituted or a substituted cyclopentadienyl ligand bonded to Zr and defined by the formula (CHR), where R is hydrogen, a hydrocarbyl substituent, a substituted hydrocarbyl substituent, or a heteroatom substituent, and where d is 0, 1, 2, 3 or 4; Land Lare connected to one another with a cyclic silicon bridge, R′SiR′, where R′ are independently hydrocarbyl or substituted hydrocarbyl substituents that are connected with each other to form a silacycle ring; and each Q is a labile hydrocarbyl or a substituted hydrocarbyl ligand.