通过内部催化和环形效应重新处理共价可适应聚胺网
Filip Van Lijsebetten1, Yann Spiesschaert1, Johan M Winne2
1Polymer Chemistry Research Group, Centre of Macromolecular Chemistry (CMaC), Department of Organic and Macromolecular Chemistry, Faculty of Sciences, Ghent University, Krijgslaan 281-S4, Ghent 9000, Belgium.
Journal of the American Chemical Society
|September 15, 2021
概括
研究人员使用自愈胺键开发了动态聚胺网络. 这些可适应的材料具有可调节的特性和敏的温度反应,使其能够进行再加工和耐高温.
科学领域:
- 聚合物化学
- 材料科学
背景情况:
- 氨基酸键通常强大且热稳定,限制了它们在动态材料中的使用.
- 开发可适应的聚合物网络需要新的策略来引入没有外部催化剂的动态特性.
研究的目的:
- 引入内部催化胺键,以创建共价适应性聚胺网络.
- 研究网络结构与热力学特性之间的关系.
主要方法:
- 通过二基和氨基化合物的直接固化过程合成动态聚胺网络.
- 研究了循环胺中间环大小对热力学粘度的影响.
- 多种类型的氨基构成块来调整网络特性和玻璃过渡温度 (Tg).
主要成果:
- 基于二胺和二胺之间的解离平衡实现了动态聚胺网络.
- 具有显著的温度反应 (激活能量:116-197 kJ mol-1) 的可调节的机械和粘弹性特性.
- 获得的网络具有广泛的Tg值 (-20至110°C) 和良好的再处理性.
结论:
- 内部催化胺键为设计先进的聚胺材料提供了多功能平台.
- 这些动态网络表现出急剧的热力学转换,将再加工能力与高温稳定性相结合.
- 开发的化学结构使得无形聚胺网络能够在各种应用中具有可调节性.
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