通过环戊二烯负离子与双富烯2,2'-二(3-亚环己基-1,4-环戊二烯基)乙醚的加成反应得到配体,所得配体锂化后与四氯化钛四氢呋喃络合物反应得到了一种新型的3-氧-戊基桥连双核(C1-桥连二茂钛)催化剂.在助催化剂甲基铝氧烷(MAO)存在下,该催化剂可以有效地催化甲基丙烯酸甲酯(MMA)本体聚合.聚合实验结果表明:MMA与该催化剂的摩尔比为1 500:1,MAO与该催化剂的摩尔比为40:1,聚合温度为60℃,反应15 h的条件下,MMA单体的转化率可达96.11%,聚甲基丙烯酸甲酯(PMMA)的黏均分子量为7.31×105,分子量分布为4.66.%A novel 3-oxa-pentamethylene bridged dinuclear C1-ansa-titanocene ( Ⅷ ) was synthesized by treating two equivalents TiCl4 ( THF ) 2 with the corresponding tetralithium salts of the ligand which were prepared by the nucleophilic addition of sodium cyclopentadienide with 2, 2'-di( 3-hexylidenyl cyclopenta-1,4-dienyl) ether. After activation with methylaluminoxane ( MAO ), the catalyst was tested for methyl methacrylate ( MMA) bulk polymerization. The result showed that under polymerization conditions of molar ratio of MMA to (Ⅷ) 1 500 ∶ 1, molar ratio MAO to ( Ⅷ) 40∶ 1,60 ℃, polymerization time 15 h, the conversion of MMA and the viscosity average molecular weight of PMMA were upto 96.11％ and 7.31 × 105 respectively. The molecular weight distribution ( MWD ) of PMMA was up to 4.66.
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