Polymerization catalysts

US6509288B1 · kind B1 · utility

Assignee

• BP Chemicals Limited · US

Inventors

• Birgit Angelika Dorer · Mutterstadt, DE
• Christopher Sharp · Beverley, GB
• Richard Weatherhead · Leatherhead, GB

Key dates

• Filing date: Nov 19, 1999
• Grant date: Jan 21, 2003
• Expiry date: Nov 19, 2019

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S526/943
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Catalyst system suitable for preparing substantially terminally unsaturated atactic polymers or copolymers of &agr;-olefins having a molecular weight (Mn) in the range 200-500,000. The catalyst system includes a metallocene of the formula:[RmCpH(5-m)][RnCpH(5-n)]M(Z)Ywherein CpH is a cyclopentadienyl ligand, each R represents an alkyl or an aryl substituent on the CpH ligand or two R's may be joined together to form a ring, or the Rs in each CpH group when taken together represents an Si or C bridging group linking two CpH groups wherein the Si or C group may itself be substituted by hydrogen atoms or C1-C3 alkyl groups, M is a metal selected from hafnium, zirconium and titanium, Z is selected from a hydrogen atom, a trifluoromethane sulphonate, an alkyl and an aryl group, Y is selected from a, 1,3-diketonate and a &bgr;-ketoester arion, and each of m and n is same or different and has a value from 0 to 5.