对共价可适应网络的直接和无催化剂转化反应
Shijia Yang1,2, Wenxing Liu3, Jing Guo1
1Beijing National Laboratory for Molecular Sciences (BNLMS), Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
Journal of the American Chemical Society
|September 15, 2023
概括
研究人员开发了一种新的无催化剂回收聚合物方法. 这一过程利用N-acyloxyphthalimide (NAPI) 中的动态共价键来创建可适应的网络,使再处理和增强材料属性.
科学领域:
- 聚合物化学
- 材料科学
- 有机化学
背景情况:
- 耐热聚合物具有优越的环境和机械性能,但由于它们的刚性和交叉连接结构,很难回收.
- 热回收是一个重大挑战,需要创新的方法来实现再加工和减少废物.
- 动态共价化学为热固化材料引入再加工能力提供了一个可行的策略.
研究的目的:
- 报告一种新型的,无催化剂的转化反应N-甲胺 (NAPI).
- 在制造共价可适应网络 (CAN) 中展示NAPI转化学的实用性.
- 研究可回收热的NAPI转化机制和动态行为.
主要方法:
- 在不需要基组的情况下,在大约100°C的温度下直接转化N-基胺 (NAPI).
- 使用NAPI转化反应制造聚网,聚N-氧胺 (PNAPI).
- 对反应动力学的分析,揭示了归因于自由基链机制的西格形行为.
主要成果:
- 在没有催化剂或基组的情况下,NAPI转化有效地进行,通过自由基链机制表现出西格形动力学和快速交换率.
- 作为基因前体和基质的NAPI的双功能性使其具有独特的分离式启动协会 (DAssociative) 机制.
- 由此产生的多酸胺 (PNAPI) 在高温下表现出优异的可塑性,耐溶剂性和机械稳定性.
结论:
- NAPI转化为制造可回收热固化聚合物提供了一个高效和多功能平台.
- 基于NAPI转化的DAssociative机制提供了高性能和可再加工的材料的途径.
- 这项工作为设计先进的,可持续的耐热材料提供了重要的机会.
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