四胺:在动态共价聚合物网络中的共价超分子双动因子
Huiyi Zhang1, Annemiek van Hertrooij1, Tobias Schnitzer1
1Institute for Complex Molecular Systems & Laboratory of Macromolecular and Organic Chemistry, Department of Chemical Engineering & Chemistry, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven, The Netherlands.
Macromolecules
|August 28, 2023
概括
1,2,4,5-四胺 (B4A) 单元通过充当交叉连接器和堆叠模块来创建强大的动态聚胺网络. 与非堆叠材料相比,这些超分子网络具有显著增强的机械性能和独特的放松动态.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 超分子化学 超分子化学
背景情况:
- 动态共价化学可以实现自我愈合和对刺激有反应的材料.
- 超分子相互作用,如键和pi堆叠,可以加强聚合物网络.
- 整合动态共价和超分子特征提供了一条通往先进材料性能的途径.
研究的目的:
- 研究1,2,4,5-四胺 (B4A) 在动态聚胺网络中作为交叉链接器和超分子动机的双重作用.
- 为了比较含有B4A的聚胺的网络动态和机械性能,与缺乏堆叠相互作用的参考材料进行比较.
- 阐明共价交叉链接和超分子堆叠对网络行为的合作贡献.
主要方法:
- 有或没有B4A图案的动态聚胺网络的合成.
- 机械测试以确定高原模量和应力松.
- 广角X射线散射 (WAXS) 和可变温度红外光谱 (VTIR) 来探测网络结构和动态.
主要成果:
- 基于B4A的网络表现出状高原模量大约是参考网络的20倍.
- 与B4A分支的聚胺形成了强大,可逆的超分子网络,而参考材料是粘性液体.
- WAXS和VTIR证实了共价交叉链接和B4A堆叠对网络动态的合作效应.
- 在B4A网络中,压力放松显示了额外的模式,归因于堆叠动态,与共价化学不同.
结论:
- 1,2,4,5-四胺 (B4A) 基因有效地通过同时共价交联和超分子堆叠来增强聚胺网络特性.
- 共价和超分子相互作用之间的合作动态导致了优越的机械强度和独特的放松行为.
- 这项研究表明,通过整合直角分子相互作用来设计先进动态材料的强大策略.
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