CATALYTIC POLYMERISATION OF OLEFINS

摘要

Ethylene copolymers having improved optical properties in film form are prepared by continuously copolymerizing ethylene with one or more higher alpha olefin monomers in a low pressure gas phase reaction with a catalyst composition prepared by forming a precursor composition from a magnesium compound, titanium compound, and electron donor compound; diluting said precursor composition with an inert carrier material; optionally partially activating the diluted precursor composition with an organo aluminum compound prior to introducing said diluted precursor composition into the polymerization reactor; and completely activating the diluted (and optionally partially activated) precursor composition in the polymerization reactor with a mixture of a dihydrocarbyl aluminum halide compound and a trihydrocarbyl aluminum compound.