ETHYLENE/.ALPHA.-OLEFIN COPOLYMER COMPOSITION, GRAFT MODIFIED ETHYLENE/.ALPHA.-OLEFIN COPOLYMER COMPOSITION, ETHYLENE COPOLYMER COMPOSITION, AND MULTI-STAGE OLEFIN POLYMERIZATION PROCESS

摘要

An ethylene/.alpha.-olefin copolymer composition comprising an ethylene/.alpha.-olefin copolymer and another ethylene/.alpha.olefin copolymer ¢B1!. The former ethylene/.alpha.-olefin copolymer can be prepared in the presence of a catalyst for olefin polymerization containing an organoaluminum oxycompound (a) and at least two kinds of specific metallocene compounds (b), and the latter ethylene/.alpha.-olefin copolymer ¢B1! can be prepared in the presence of a catalyst for olefin polymerization containing an organoaluminum oxycompound (a) and a specific metallocene compound (b'). A graft modified ethylene/.alpha.-olefin copolymer composition obtained by graft copolymerizing an ethylene/.alpha.olefin copolymer composition with a polar monomer. The ethylene/.alpha.-olef1n copolymer composition comprises an ethylene/.alpha.-olefin copolymer prepared in the presence of a catalyst for olefin polymerization containing an organoaluminum oxy-compound (a) and a specific metallocene compound (b'), and the above ethylene/.alpha.-olefin copolymer ¢B1!. An ethylene copolymer composition comprising the above-mentioned graft modified ethylene/.alpha.-olefin copolymer composition and polyolefin. A multi-stage olefin polymerization process comprising a stage of preparing an ethylene/.alpha.-olefin copolymer ¢A1! in the presence of a catalyst for olefin polymerization containing an organoaluminum oxy-compound (a), a specific metallocene compound (b-I) and a specific metallocene compound (b-II) and a stage of preparing an ethylene/.alpha.olefin copolymer ¢B1! in a different polymerizer from that for the copolymerization reaction of the above stage in the presence of a catalyst for olefin polymerization containing an organoaluminum oxy-compound (a) and a specific metallocene compound (b'). The ethylene/.alpha.-olefin copolymer composition of the invention is excellent in heat stability and moldability. From this composition, a film of high transparency, high mechanical strength and high blocking resistance can be produced. The graft modified ethylene/.alpha.-olefin copolymer composition of the invention is excellent in moldability. From this composition, a film having high transparency and good adhesion to highly polar materials can be produced. The ethylene copolymer composition of the invention is excellent in moldability. From this composition, a film having high transparency and good adhesion to highly polar materials can be produced. The multi-stage olefin polymerization process of the invention can prepare an ethylene/.alpha.-olefin copolymer composition of good heat stability and moldability from which a film of high transparency and high mechanical strength can be produced.