Abstract: A cocatalyst system for olefin polymerization comprises an aluminoxane (especially methylaluminoxane, or “MAO”), an aluminum alkyl and a halogenated phenol. The preferred halogenated phenol is pentafluorophenol. The use of pentafluorophenol permits the substitution of a portion of the MAO cocatalyst (which is expensive) with inexpensive aluminum alkyl. The cocatalyst is most preferably employed in combination with an organometallic catalyst having at lease one pi ligand.

Abstract: A blend of ethylene homopolymers contains at least one blend component having a very low molecular weight and a narrow molecular weight distribution. The blend has surprisingly high density and low hexane extractables. The blend is suitable for the manufacture of a wide variety of plastic goods including extruded goods and molded goods. Plastic film prepared from the blends of this invention have a low Water Vapor Transmission Rate (“WVTR”).