从含有环素和终端基因的单体中快速串联环开/环闭转化聚合
1Department of Chemistry, Seoul National University, 599 Gwanak-ro, Gwanak-gu, Seoul 151-747, Korea.
Journal of the American Chemical Society
|April 20, 2012
概括
研究人员使用格鲁布斯催化剂开发了一种快速聚合方法,用于挑战单体. 这一突破使控制的聚合物合成和先进材料的多功能后功能化成为可能.
科学领域:
- 聚合物化学 聚合物化学
- 有机合成 有机合成
- 催化剂是一种催化剂.
背景情况:
- 环开/环闭元解聚合 (ROMP/RCM) 是聚合物合成的一个强大的工具.
- 具有非反应性功能组的单体,如环烯和终端基因,对受控聚合构成重大挑战.
- 为此类单体开发高效的催化系统对于扩大聚合物设计能力至关重要.
研究的目的:
- 报告一个含有环素和终端基因的单体的极快串联环开/环闭转化聚合.
- 为了研究负责高聚合率的反应机制.
- 证明这种方法在创建新型聚合物架构,包括块共聚合物和功能化聚合物方面的实用性.
主要方法:
- 使用第三代格鲁布斯催化剂进行双重聚合.
- 在低温下进行聚合,以实现控制.
- 采用技术来研究反应机制.
- 通过连续的Diels-Alder和aza-Diels-Alder反应,通过得到的聚合物骨干进行后功能化.
主要成果:
- 实现了一个具有挑战性的单体的极快的串联环开/环闭元解聚合.
- 生产的聚合物具有受控的分子量和狭窄的多分散度指数.
- 阐明了促进快速聚合的反应机制.
- 通过将这种方法与其他活体转化聚合物集成,成功合成了块共聚合物.
- 基于二烯立体化学,证明了聚合物骨干的选择性后功能化.
结论:
- 开发的双重聚合提供了一个高效的途径,从不反应的单体聚合物到聚合物.
- 聚合物的受控性质允许精确的聚合物架构设计.
- 后功能化策略为具有可调节性质的多种功能材料提供了途径.
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