基合金复合的锡尔科诺水化物作为参与者在烯聚合催化剂的聚合
Steven M Baldwin1, John E Bercaw, Hans H Brintzinger
1Arnold and Mabel Beckman Laboratories of Chemical Synthesis, California Institute of Technology, Pasadena, California 91125, United States.
Journal of the American Chemical Society
|September 24, 2010
概括
一种新型的科诺三水化物离子催化异性聚烯的形成. 在trimethylaluminum的存在下,它转化为甲基桥接离子,改变聚合过程和产品.
科学领域:
- 有机金属化学 有机金属化学
- 聚合物科学 聚合物科学
- 催化剂是一种催化剂.
背景情况:
- conocene复合物是olefin聚合中的重要催化剂.
- 了解催化剂的特异化和转化对于控制聚合物特性至关重要.
研究的目的:
- 为了研究基复合体基三化酸盐的催化行为.
- 阐明三甲基在改变催化剂的活性物种和聚合机制中的作用.
主要方法:
- 使用特定的前体和试剂合成conocene三化.
- 在低温 (-30°C) 上进行烯聚合实验.
- 在有或没有三甲基的情况下对催化剂物种的分析.
主要成果:
- conocene三水化物子有效地催化了异性聚烯的形成.
- 在trimethylaluminum的存在下,三化离子通过光化转化为双甲基桥接离子.
- 这种转换的变为静止状态,导致AlMe(2) 覆盖的聚烯.
结论:
- 这项研究揭示了由共催化剂存在影响的动态催化剂转换.
- 这种转化显著影响了聚合途径和最终的聚合物结构,产生了Al-capped聚烯.
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