Synthesis and characterization of high molecular weight atactic polybutene-1 and butene-1 polymerization catalyzed by titanocene/MAO catalyst

(eta(5)-Pentamethylcyclopentadienyl) titanium triallyioxide [Cp * Ti (OCH2-CH = CH2)(3)] was used as the catalyst precursor for the synthesis of polybutene-1, methylalumiunoxane (MAO) as cocatalyst. The effects of the ratio of n(Al) to n(Ti), polymerization temperature, and concentration of Ti on catalytic activity, molecular weight and chain structure were investigated in detail. The ether-soluble fraction of the polybutene-1 was characterized with C-13 NMR, DSC, WAXD, and GPC. The results indicate that the polymers thus obtained are atactic and regioirregular, the weight average molecular weight of these polymers lies in the range of 3.0 X 10(5) to 7.0 X 10(5). Increasing the polymerization temperature can result in a decrease in the polymer molecular weight. But the molecular weight varies slightly with the ratio of n (AD to n(Ti). The catalytic activity tends to decrease with the increase in polymerization temperature.