通过可光切换催化剂策略量身定制聚合的可控性和分散性
Zhuan Chen1, Yue Sun2, Xin Wang1
1Suzhou Key Laboratory of Macromolecular Design and Precision Synthesis, College of Chemistry Engineering and Materials Science of Soochow University, Suzhou, 215123, P. R. China.
Macromolecular rapid communications
|May 26, 2023
概括
研究人员使用可光切换催化剂实现了按需聚合控制,用于单电子转移介导的活基聚合 (SET-LRP). 这种方法可以通过打开和关闭灯光来控制聚合和聚合物分散的可逆控制.
科学领域:
- 聚合物化学 聚合物化学
- 宏分子科学 宏分子科学
- 有机合成 有机合成
背景情况:
- 控制按需聚合仍然是合成宏分子化学的一个重大挑战.
- 活基聚合技术可以提高对聚合物结构的控制,但往往缺乏外部可调性.
- 单电子转移介导的活基聚合 (SET-LRP) 为受控聚合物合成提供了一个平台.
研究的目的:
- 开发一种可光切换的催化剂,用于精确控制甲基甲基酸盐 (MMA) 的SET-LRP.
- 为了实现聚合化动力学和聚合物分散性的按需调制.
- 为了实现聚合过程的可重复重置.
主要方法:
- 使用六二胺醇 (HABI) 作为可光切换的催化剂.
- 采用光照辐射可逆地切换HABI在活跃和非活跃状态之间.
- 在不同的光照条件下研究了MMA的SET-LRP.
主要成果:
- 使用HABI证明了对MMA的SET-LRP的可逆控制.
- 当催化剂活跃时 (灯亮) 实现了第一阶聚合动力学和狭窄的分子量分布.
- 展示了通过关闭催化剂 (关灯) 来重置聚合的能力,允许可重复的控制.
结论:
- 在SET-LRP中,HABI充当了一种高效的分子开关,用于SET-LRP中的光调节聚合分散.
- 拟议的机制阐明了HABI在SET-LRP中的可切换的催化活性.
- 这项工作为按需聚合控制和聚合物合成提供了一个新的策略.
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