Alternating copolymerization of ethylene and propene with the [ethylene(1-indenyl)(9-fluorenyl)]zirconium dichloridemethylaluminoxane catalyst system

The copolymerization of ethylene and propene was conducted at ?40°C with the ethylene(1-indenyl)(9-fluorenyl)]zirconium dichloride-methylaluminoxane catalyst system, and the microstructure of the resulting copolymers was analyzed in detail by ¹³C NMR. The content of alternating EP] sequences increased markedly with an increase in the feed ratio of propene to ethylene. A poly(ethylene-co-propene) with a proportion of EP] sequences over 95% was thus obtained under appropriate copolymerization conditions. It was also demonstrated that the alternating ethylene-propene copolymer is stereoregular and isotactic.