Supported metallocene catalysts

US6855783B2 · kind B2 · utility

Assignee

• Fina Technology, Inc. · US

Inventors

• William Gauthier · Houston, US
• Margaret Kerr · Worcester, US
• Jun Tian · League City, US
• David Rauscher · Webster, US
• Constance Hayworth Patrick · Conroe, US
• Shady Henry · La Porte, US

Key dates

• Filing date: Apr 11, 2003
• Grant date: Feb 15, 2005
• Expiry date: Apr 11, 2023

Classification

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

Abstract

Supported metallocene catalysts and processes for the use of such catalysts in isotactic polymerization of a C3+ ethylenically unsaturated monomer. The supported catalysts comprise a particulate silica support, an alkyl alumoxane component, and a metallocene catalyst component. The support has an average particle size of 10-50 microns, a surface area of 200-800 m2/g and a pore volume of 0.9-2.1 milliliters per gram (ml/g). Alumoxane is incorporated onto the support to provide a weight ratio of alumoxane to silica of at least 0.8:1. The metallocene is present in an amount of at least 1 weight percent of the silica and the alumoxane and is of the formula B(CpRaRb)(Fl′)MQ2 in which Fl′ is an unsubstituted fluorenyl group or a fluorenyl group symmetrically substituted at the 3 and 6 positions, B is a structural bridge between Cp and Fl′, Ra is a bulky substituent in a distal position, Rb is a less bulky substituent proximal to the bridge and non-vicinal to the distal substituent, M is a Group IVB transition metal or vanadium, and Q is a halogen or a Cl-C4 alkyl group.