Synthesis and Characterization of High Molecular WeightAtactic Polybutene-1 with a Monotitanocene/Methylaluminoxane Catalyst System
A novel catalyst precursor, the monotitanocene (h5-pentamethylcyclopentadienyl)
titanium tricinnamyloxide [Cp*Ti(OCH2OCHACHC6H5)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 5.3–9.6 3 105), and stereoirregularity
with the Bernoullian factor B equal to 0.95, which indicates that
chain-end control is predominant. © 2001 John Wiley & Sons, Inc. J PolymSci Part A: Polym
Chem 39: 4068–4073, 2001
Keywords: butene-1 polymerization; monotitanocene; methylaluminoxane; high molecular
weight; atactic polybutene-1; elastomer