Fina Technology, Inc.

Donald Gordon Campbell, Jr

Margarito Lopez

Edwar Shoukri Shamshoum

William John Gauthier

Supported stereospecific catalysts and processes for the stereotactic propagation of a polymer chain derived from ethylenically unsaturated monomers which contain three or more carbon atoms or which are substituted vinyl compounds, specifically alpha olefins, particularly the polymerization of propylene to produce syndiotactic or isotactic polypropylene. The supported metallocene catalyst comprises a stereospecific metallocene catalyst and a co-catalyst component comprising at least one of an alkyl alumoxane and an alkylaluminum compound. Both the metallocene catalyst and the co-catalyst are supported on a particulate silica support comprising silica particles having an average particle size of 5-40 microns and an average effective pore size of 50-200 angstroms. The silica support further has a differential pore size distribution of a pore volume of at least 0.01 cm/g. within a range having a maximum pore width of no more than 300 angstroms. The metallocene has a retention factor on this support of at least 90 wt. % after aging in tri-isobutylaluminum at a temperature of 25&#xb0; C. for a period of 12 hours.

Supported metallocene catalysts and their use in producing stereospecific polymers

Supported stereospecific catalysts and processes for the stereotactic propagation of a polymer chain derived from ethylenically unsaturated monomers which contain three or more carbon atoms or which are substituted vinyl compounds, specifically alpha olefins, particularly the polymerization of propylene to produce syndiotactic or isotactic polypropylene. The supported metallocene catalyst comprises a stereospecific metallocene catalyst and a co-catalyst component comprising at least one of an alkyl alumoxane and an alkylaluminum compound. Both the metallocene catalyst and the co-catalyst are supported on a particulate silica support comprising silica particles having an average particle size of 5&#x2013;40 microns and an average effective pore size of 50&#x2013;200 angstroms. The silica support further has a differential pore size distribution of a pore volume of at least 0.01 cm/g. within a range having a maximum pore width of no more than 300 angstroms. The metallocene has a retention factor on this support of at least 90 wt. % after aging in tri-isobutylaluminum at a temperature of 25&#xb0; C. for a period of 12 hours.

A process for the preparation of a supported metallocene catalyst incorporating metallocene and co-catalysts components on a support. There is provided a particulate catalyst support material in which an alumoxane co-catalyst is incorporated onto the support particles and contacted with a dispersion of a metallocene catalyst in an aromatic hydrocarbon solvent. The metallocene solvent dispersion and the alumoxane-containing support are mixed at a temperature of about 10&deg; C. or less for a period sufficient to enable the metallocene to become reactively supported on the alumoxane support material. The supported catalyst is recovered from the aromatic solvent and then washed optionally with an aromatic hydrocarbon and then sequentially with a paraffinic hydrocarbon solvent at a temperature of about 10&deg; C. or less. The washed catalyst is dispersed in a viscous mineral oil having a viscosity which is substantially greater that the viscosity of the paraffinic hydrocarbon solvent.

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Webster, TX, United States of America

Donald Gordon Campbell, Jr