通过有机催化剂从环氧混合物中构建富含氧的区块共聚物
Yao-Yao Zhang1, Guan-Wen Yang1, Rui Xie1
1MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China.
Journal of the American Chemical Society
|October 18, 2022
概括
这项研究引入了一种可切换的新型催化方法,用于精确地从混合环氧化物中合成块共聚物. 该技术通过在不同的大气条件下利用不同的环氧反应来控制聚合,从而实现序列控制.
科学领域:
- 聚合物化学
- 催化剂
- 材料科学
背景情况:
- 使用可切换催化和环氧化开环聚合物合成块共聚物.
- 由于类似的环应变,对环氧原体的序列控制聚合具有挑战性.
- 双功能器官催化剂对环氧化物转换具有前景.
研究的目的:
- 开发一种由序列控制的聚合法,用于从环氧化物混合物中制造的块共聚物.
- 使用可切换的催化剂来控制聚乙-聚碳酸和聚乙-聚共聚合物的合成.
- 通过使用双功能器官催化剂,研究选择性环氧化物开放的机制.
主要方法:
- 使用含有四级/的双功能机能催化剂开发了一种操作简单的途径.
- 在不同的大气层 (CO2或N2) 下使用可切换的催化剂,以实现终端或内部环开放.
- 使用NMR,MALDI-TOF和凝透色谱对合成的块共聚物进行了表征.
- 进行了动力学研究和密度功能理论 (DFT) 计算,以阐明反应机制.
主要成果:
- 从终端和内部环氧化物混合物中成功合成了明确的聚乙块聚碳酸共聚物.
- 通过根据大气条件 (CO2或N2) 选择性地打开不同的环氧化物来证明序列控制.
- 通过用循环无水化物取代二氧化碳,扩展了合成聚乙烯-块-聚乙烯共聚物的方法.
- 通过先进的分析技术证实了合成块共聚物的结构和分子量.
结论:
- 使用可切换催化剂从环氧混合物中实现了第一个序列控制的聚合.
- 开发的方法为制造各种富含氧气的块共聚物提供了广泛的基材范围.
- 这项工作扩大了可切换催化剂的功能聚合物的可控合成能力.
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