选择性转化控制共聚物微结构在环开放共聚化乳和e-caprolactone由兰复合体
Bette Beament1, Daniel Britton1, Thomas Malcomson2
1Department of Chemistry, Lancaster University, Lancaster LA1 4YB, United Kingdom.
Inorganic chemistry
|December 21, 2023
概括
新型兰胺复合物催化乳酸盐和酸盐的环开聚合. 催化剂结构和溶剂控制共聚合物微结构,使得定制的聚合物特性.
科学领域:
- 协调化学 协调化学
- 聚合物科学 聚合物科学
- 催化剂是一种催化剂.
背景情况:
- 兰复合物越来越多地被用于催化应用.
- 萨兰联体为金属复杂设计提供可调节的硬质和电子特性.
- 环开聚合 (ROP) 是合成可生物降解聚合物的关键方法.
研究的目的:
- 为了合成和表征新的胺复合物与基于萨兰的配体.
- 研究这些复合物的催化活性在乳化物 (LA) 和e-caprolactone (e-CL) 的ROP中.
- 探索催化剂结构和反应条件对共聚合和微观结构的影响.
主要方法:
- 胺复合物的合成和完整表征.
- 催化研究LA和ε-CL的同聚合和共聚合.
- 使用凝透色谱-大小排除色谱 (GPC-SEC) 分析反应产品.
主要成果:
- 新的胺复合物成功合成和特征化.
- 催化剂在LA聚合和LA/ε-CL共聚合中表现出高活性.
- 溶剂和连接物替代剂 (基) 显著影响了催化剂的反应性和选择性.
- 聚合物微结构 (块化到交替) 可以通过催化剂设计和溶剂选择进行调整.
- 发现转化机制 (TI或TII) 取决于催化剂和溶剂.
结论:
- 兰氨基复合物是LA和e-CL聚合物的有效催化剂.
- 催化剂结构和反应溶剂对于控制共聚合物组成和微观结构至关重要.
- 这项工作为设计催化剂提供了一条途径,以实现特定的聚特性.
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