最小的N-基甲胺-尿键使得共价适应性网络具有卓越的热力学稳定性
Yuhan Yin1,2, Shijia Yang1,2, Yong Zhou3
1Beijing National Laboratory for Molecular Sciences (BNLMS), Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing, China.
Nature communications
|March 3, 2026
概括
本研究介绍了使用动态N-甲胺-尿氨键 (NUB) 的共价适应性网络 (CAN) 的新策略. 这种方法可以提高再加工性和机械稳定性,而不会影响性能.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 传统的热聚材料缺乏再加工能力,这是一个关键的限制.
- 联适应性网络 (CAN) 提供可重加工性,但往往牺牲机械性能和热稳定性.
- 动态共价键 (DCB) 对CAN的适应性至关重要.
研究的目的:
- 为CANs制定"高活动和低内容"战略.
- 为了在CAN中实现卓越的热力学稳定性和再加工性.
- 在动态聚合物中克服机械性能和可再加工性之间的权衡.
主要方法:
- 对于CANs,利用了动态的N-甲胺-尿键 (NUBs).
- 采用了N-hydroxyphthalimides和异酸盐之间的无催化剂添加反应.
- 加入了低含量 (5mol%) 的动态单元,以创建多N-氧甲胺-尿素 (PNU) 网络.
主要成果:
- 在室温下在2小时内实现了近量化转换.
- 在120°C时,证明了高达~28%的债券解离.
- 开发了具有卓越机械性能,裂耐受性和高温稳定性的PNU网络.
- 在中性水的条件下表现出极好的再加工性和轻度降解性,DCB含量最小.
结论:
- "高活性和低含量"战略有效地平衡了CAN的再加工能力和热力学稳固性.
- NUB 能够实现高效的动态特性,同时降低了 DCB 的含量.
- 这种方法克服了动态聚合物的传统局限性,提供了更好的性能和可持续性.
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