CO2 基聚碳酸通过循环碳酸的环开聚合,由 NHC 基复合物促进
Federica Tufano1,2, Claudia Napolitano1,2, Mina Mazzeo1,2
1Department of Chemistry and Biology "Adolfo Zambelli" University of Salerno, via Giovanni Paolo II, 132, 84084 Fisciano, SA, Italy.
Biomacromolecules
|June 25, 2024
概括
一种新型的N-异环碳酸催化剂使三甲烯碳酸盐 (TMC) 的受控环开放聚合变为多甲烯碳酸盐 (PTMC) 成为可能. 这种方法产生了可调节的分子质量和低分散度的聚合物,最大限度地减少了副作用.
科学领域:
- 聚合物化学 聚合物化学
- 有机金属化学 有机金属化学
- 材料科学 材料科学 材料科学
背景情况:
- 环开聚合 (ROP) 对于合成可生物降解聚合物至关重要.
- N-异环碳化合物 (NHC) 复合物具有可调节的催化性能.
- 对循环碳酸盐的受控聚合仍然是一个挑战.
研究的目的:
- 为三甲烯碳酸盐 (TMC) 的 ROP 开发一种有效的催化剂.
- 为了实现受控的分子质量和低分散在聚二甲基碳酸 (PTMC) 合成.
- 探索催化剂聚合替代循环碳酸盐并形成块共聚合物的能力.
主要方法:
- 使用脊柱替代的NHC复合物与酒精启动器用于ROP.
- 使用MALDI-ToF和NMR光谱学进行PTMC的特征.
- 在溶液中研究了聚合动力学和聚合机制.
- 来自可再生原料的合成和聚合替代循环碳酸盐.
- 已制备的聚碳酸/聚乙烯和聚碳酸/聚酸块共聚合物.
主要成果:
- 实现了 TMC 到 PTMC 的受控 ROP,其分子质量为 (250010000) 和低分散度 (Đ ≈ 1.2).
- 通过改变酒精启动剂,证明了PTMC与各种末端组的形成,包括远程聚合物.
- 证实了ROP系统的受控/活体性质,最大限度地减少了转化副作用.
- 展示了对2-MeTMC具有良好的区域选择性 (Xreg高达0.92) 的替代循环碳酸盐的聚合.
- 通过使用PEG和聚酸成功合成了triblock和di-/triblock共聚合物.
结论:
- NHC复合体是控制TMC的ROP的高效催化剂.
- 该系统允许精确控制聚合物架构,分子量和终端组功能.
- 这种催化方法是多功能性的,使复杂的聚合物结构从可再生资源的合成.
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