文献类型：期刊文献

中文题名：双核茂钛催化剂中苄基苯环的弱作用效应对乙烯聚合行为影响的研究

英文题名：Study on the Influence of the Weak Effect of Benzyl Benzene Ring on the Polymerization Behavior of Ethylene

作者：许胜[1];梁春超[1];吕中文[1];朱玉玲[1];张翠[1];米普科[1]

机构：[1]华东理工大学化学与分子工程学院,上海200237

年份：2017

卷号：37

期号：5

起止页码：1284

中文期刊名：有机化学

外文期刊名：Chinese Journal of Organic Chemistry

收录：CSTPCD;;Scopus;WOS:【SCI-EXPANDED(收录号:WOS:000404624000026)】；北大核心:【北大核心2014】；CSCD:【CSCD2017_2018】；

基金：Project supported by the National Natural Science Foundation of China (No. U1362111).

语种：中文

中文关键词：苄基;双核茂金属;弱效应;共聚;机理

外文关键词：benzyl; binuclear metallocene; weak effect; copolymerization ability; mechanism

摘要：为了研究茂环上的苄基对双核茂金属催化行为的影响,合成了含有苄基的桥连双核茂金属[(η~5-C_5H_5)TiCl_2(η~5-(C_6H_5)C(Me)_2(C_5H_3)]2[μ,μ-1,4-(CH_2)2(C_6H_4)][(TiBz)_2],通过~1HNMR、^(13)C NMR、质谱和元素分析进行了表征,确认了化学结构.在甲基铝氧烷(MAO)助催化作用下(TiBz)_2催化乙烯聚合得到C(4)支链的聚乙烯,C(4)支链源自于苄基苯环弱作用效应导致的乙烯三聚产生的1-己烯对聚乙烯插入.该催化体系具有很好的共聚能力,催化乙烯与1-己烯共聚时,聚合物中1-己烯插入率高达13.7 mol%,且形成交替共聚片段结构.对其特殊的催化循环机理进行了探讨,苄基苯环与中心金属弱相互作用导致1-己烯与乙烯分子交替插入得到己烯乙烯交替共聚(HEHE)片段,聚合物较窄的分子量分布(PDI=2.23)表明,在聚合过程中两个金属中心产生了强烈的协同效应,使其共聚能力大幅度提高.
In order to study the effect of the benzyl benzene ring on the catalytic behavior of binuclear metallocene, the binu- clear metallocene [（η~5-C_5H_5）TiCl_2（η~5-（C_6H_5）C（Me）_2（C_5H_3）]2[μ,μ-1,4-（CH_2）2（C_6H_4）][（TiBz）_2]is synthesized and characterized by IH NMR, J3C NMR, mass spectra and elemental analysis. When combined with methylaluminoxane （MAO）, the （TiBz）2/MAO system catalyzed ethylene polymerization and the polymer with C（4） branch were obtained. It is suggested that the C（4） branch is from the ethylene trimerization by the weak effect between the benzyl and center metal. The （TiBz）2/MAO system also showed great ability for ethylene copolymerization with 1-hexene and the incorporation of 1-hexene in polymer reached up to 13.7 mol%. The 13C NMR result of polymer showed that the polymer contained alternatively copolymerized HEHE fragment and the possible mechanism is presented for explaining the special catalytic behavior. It is the weak effect between the benzyl and center metal that led to the alternative insertion of ethylene and 1-hexene, and the narrow molecular weight distribution （PDI=2.23） meant that there could be a great synergistic effect between the two activate center metals in the polymerization process, which greatly increased the copolymerization capability.