一种六元环桥连茂金属化合物催化乙烯聚合

Ethylene Polymerization Catalyzed by Cyclohexyl-bridged Cyclopentadienyl Titanium Complex

含六元螺环桥连双环戊二烯配体C1与正丁基锂和TiCl4·2THF反应，生成相应的桥连茂基钛化合物[（CH2）5C（C5H4）2]TICl2（C2）．以（1HNMR）和（13CNMR）以及元素分析表征了该化合物．在MAO（Methyl Aluminoxane）助催化下，化合物C2成功催化乙烯聚合．催化体系在60～70℃显示出高活性，反应温度低于60℃条件下所得聚乙烯（PE）粘均分子量（Mv）超过34万．GPC测定结果说明聚合物分子量分布较窄（PDI=2．69），具有茂金属催化剂典型的单活性中心特征．DSC测试结果表明，所得聚合物为低支化度高熔点线形聚乙烯．

Cyclohexyl-bridged cyclopentadienyl titanium catalyst of the type [ （CH2） 5C（C5 H4 ） 2] TICl2 （C2） has been prepared by treatment of the lithium salt of cyclopentadiene ligand with TIC14 ·2THF in THF solution. The complex C2 were characterized by 1H-NMR,13C-NMR and element analyse. Activated by MAO, complex C2is an efficient catalyst in the polymerization of ethylene. Complex C2 displayed very high activity for ethylene polymerization under the reaction temperature of 60-70 ℃ ,and the viscosity-average molecular weight of polyethylene is more than 3.4）〈 10^5 when reaction temperature is no more than 60 ℃ . The molecular-weight distribution measured by gel permeation reached 2. 69 . High melting points measured by DSC indicates that the polyethylene produced by complex C2 is high linearity and high crystallinity.