使用高效)) 催化系统的乳化聚合物的机械方面
Carine Robert1, Thibault E Schmid1, Vincent Richard1
1Chimie ParisTech, PSL Research University, CNRS , Institut de Recherche de Chimie Paris, 75005 Paris, France.
Journal of the American Chemical Society
|April 12, 2017
概括
一种新型的催化剂,通过连体稳定,在室温下有效启动rac-lactide的环开聚合 (ROP). 这一突破提供了一种简单,高产的方法,
科学领域:
- 聚合物化学
- 有机金属化学
- 催化剂
背景情况:
- 环开聚合 (ROP) 对于合成可生物降解的聚合物,如聚胺至关重要.
- 开发高活性和可访问的ROP催化剂仍然是一个重要的研究目标.
- 现有的方法通常涉及复杂的催化剂制备和净化.
研究的目的:
- 报告一种新的,高活性基启动剂用于rac-lactide的ROP.
- 开发一种简单而强大的催化系统,以高效地合成聚胺.
- 使用计算研究阐明启动和传播的机制.
主要方法:
- 在C2-对称salen连接体稳定启动器的现场生成.
- 使用开发的催化剂系统对rac-lactide进行环开聚合 (ROP).
- 用密度功能理论 (DFT) 研究反应机制.
主要成果:
- 在室温下,盐复合体对rac-lactide ROP表现出前所未有的高活性.
- 这种由复合物和洋盐制成的催化剂系统提供了高产量的聚酸.
- 实现了狭窄的多分散度指数,表明受控的聚合.
- DFT研究证实了在启动和繁殖过程中对协调的单体的外部氧化物攻击.
结论:
- 已经开发出一种高效且易于使用的聚胺合成催化系统.
- 这种新方法避免了复杂而昂贵的催化剂制备,使其具有工业意义.
- 机械学见解为设计未来的聚合催化剂提供了基础.
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