Improved method and catalysts for producing polymer for blow molding applications

摘要

A catalyst and method for producing olefin polymers having high MFR and reduced die swell for use in blow molding applications is provided. The polymers are produced by fluidized bed polymerization of ethylene and optionally one or more alpha olefins at elevated temperatures in the presence of a spherical or microspherical, supported chromium-titanium catalyst having a refractory oxide support material that has at least 70% of its pore volume in the pore size range of about 200 to 500 Angstroms, which supported catalyst has been activated at a temperature ranging from about 850 DEG C to the sintering temperature of the supported catalyst.