Synthesis and characterization of high molecular weight atactic polybutene-1 with a monotitanocene/methylaluminoxane catalyst system

A novel catalyst precursor, the monotitanocene (eta (5)-pentamethylcyclopentadienyl) titanium tricinnamyloxide [Cp*Ti(OCH2-CH-CHC6H5)(3)], was synthesized and employed for butene-1 polymerization in the presence of methylaluminoxane. The effects of the polymerization conditions on the catalytic activity, molecular weight, stereoregularity, and regioregularity of the polymer so obtained were investigated in detail. The results show that the monotitanocene is desirable for the production of atactic polybutene-1 coupled with good yields under typical polymerization conditions, high molecular weight (weight-average molecular weight = 5.3-9.6 x 10(5)) and stereoirregularity with the Bernoullian factor B equal to 0.95, which indicates that chain-end control is predominant. (C) 2001 John Wiley & Sons, Inc.