HIGH EFFICIENCY CATALYST CONTAINING TITANIUM AND ZIRCONIUM FOR POLYMERIZING OLEFINS; POLYMERIZATION OF OLEFINS IN THE PRESENCE OF A CATALYST CONTAINING TITANIUM AND ZIRCONIUM

摘要

Olefins are polymerized in the presence of a catalyst prepared by reacting trivalent or tetravalent titanium compounds such as a titanium trichloride or a titanium tetraalkoxide, zirconium compounds such as tri-n-butoxy zirconium chloride, an organomagnesium component such as di-n-hexyl magnesium, a halogen source such as ethyl aluminum dichloride and an organoaluminum compound if the halide source or magnesium component does not contain sufficient quantities of aluminum. Polymerization processes employing these catalyst compositions do not require conventional catalyst removal steps in order to provide polymers having suitable color and other physical characteristics and these catalysts produce polymers having broader molecular weight distributions and, at higher zirconium amounts, lower melt indices than do corresponding catalysts without the zirconium compound.