氨酸终结聚乙烯的有机胺催化合成
Amber M Kawaoka1, Tobin J Marks
1Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208-3113, USA.
Journal of the American Chemical Society
|October 8, 2004
概括
这项研究结合了有机兰化物介导的化和乙烯聚合. 它引入了diphenylphosphine作为olefin聚合物的有效链传递剂,产生了功能化的聚合物.
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:
- 奥莱芬聚合是聚合物生产的基石.
- 开发具有功能终端组的受控聚合过程对于先进材料至关重要.
- 有机兰化物复合物为氨酸转化提供独特的催化性能.
研究的目的:
- 为了将有机兰化物介导的水化与乙烯聚合相结合.
- 调查二四因作为单位催化系统中的链传递剂的作用.
- 为了合成具有受控分子量的二基末聚乙烯.
主要方法:
- 使用一种催化循环,将水化和乙烯聚合结合起来.
- 使用1H,13C和31PNMR,凝透色谱 (GPC) 和差分扫描热量计 (DSC) 进行了生成聚合物的特征.
- 将聚合物特性与一个模型化合物,1-eicosyldiphenylphosphine氧化物进行比较.
主要成果:
- 实现了高催化活性 (107 g聚合物/(mol Ln.atm乙烯.h)) 用于聚合/链转移过程.
- 观察到狭窄的多分散性,表明聚合物生长受控.
- 证明了聚乙烯分子量与二烯胺度之间的反向关系,证实了链转移.
结论:
- 使用有机兰化物成功合化和聚合.
- 确立了基氨酸作为单位f和d电子金属介导的单位f和d电子金属介导的烯聚合物的有效链传递剂.
- 这项工作开创了使用富含电子的氨酸来控制烯聚合物的功能化.
相关概念视频
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