Stereoregular and Bernoullian copolymerization of styrene and ethylene by bridged metallocene catalysts

A stereoregular and Bernoullian copolymer of styrene and ethylene was produced by the catalyst system of rac-[isopropylidenebis(1-indenyl)]zirconium dichloride and MAO. This catalyst system yields a high molecular weight copolymer with good activity at 50°C. The copolymer consists of Et-Et, St-Et, and head to tail St-St sequences and has a highly isotactic Et-St alternating sequence. This copolymer shows a melting point (80 – 110°C), due to the isotactic alternating sequence.