单茂钛催化剂催化丁烯-1聚合及高分子量无规聚丁烯-1的合成与表征

Kaminsky等 [1,2 ] 用二茂基 ( Cp,Ind,Flu)过渡金属 ( Ti,Zr和 Hf)化合物 /MAO催化剂催化丁烯 - 1聚合 ,得到间规 -等规或间规 -等规 -无规的混合物 ,聚合物的分子量为 5 0 0 0 0至 1 5 0 0 0 0 .Rossi[3] 用( CH3) 2 Si( H4 Ind) 2 Zr Cl2 /MAO研究了丁烯 - 1的等规聚合 ,产物分子量仅 2 0 0 0左右 .林尚安等[4 ,5] 采用单茂钛催化剂 Cp* Ti( OBz) 3/MAO催化丁烯 - 1聚合 ,产物为立体多嵌段聚丁烯 - 1 .但目前尚未见到有关采用茂金属催化剂催化丁烯 - 1聚合制备高分子量无规弹性体聚丁烯 - 1的报道 .我们用单茂钛 Cp* Ti( OC…

Synthesis and Characterization of High Molecular Weight Atactic Polybutene-1 and Butene-1 Polymerization Catalyzed by Titanocene/MAO Catalyst

(η⁵-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 ¹³ C 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 3.0×10⁵ to 7.0×10⁵. 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 (Al) to n (Ti). The catalytic activity tends to decrease with the increase in polymerization temperature. 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.The catalytic act ivity tends to decrease w ith t he increase in polym erizat ion tempera-ture.