立体化学调节的气结合协同共价适应性网络:朝着回收弹性体,具有优异的抗性能
Zhenghuai Feng1, Miao Xie2, Jialiang Lai1
1State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute, Sichuan University, Chengdu, 610065, China.
Angewandte Chemie (International ed. in English)
|January 21, 2025
概括
胺扩展剂中的立体化学决定了聚氨的特性. 转换配置的聚氨提供优越的爬行阻力,而 cis 配置的聚氨提供了增强的弹性和可加工性,使可回收的耐热材料成为可能.
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
- 有机化学 有机化学
背景情况:
- 共价适应性网络 (CAN) 为热聚合物回收提供了机会.
- 在CAN中平衡再加工易度和爬行阻力是一个重大挑战.
- 聚氨 (PU) 是一种具有可回收性的热材料的关键类别.
研究的目的:
- 通过控制胺链扩展器立体化学,设计和合成具有可调节性质的聚氨材料.
- 调查 cis-和 trans-diamine 配置对机械性能,爬行抵抗性和可回收性的影响.
- 为高性能,可回收的PU建立结构-属性关系.
主要方法:
- 使用 cis 和 trans 配置的二胺链延长器合成聚氨材料.
- 机械测试用于评估诸如抗和弹性之类的性能.
- 使用热压和溶热方法通过尿素键交换进行回收研究.
- 密度函数理论 (DFT) 计算来分析结相互作用.
主要成果:
- 转换配置的PU (R,R-DAC-PU,S,S-DAC-PU) 由于密集的结合,表现出优越的爬行阻力和机械强度.
- 配置为Cis的PU (Cis-DAC-PU) 显示出增强的可加工性和弹性.
- 在60分钟的时间内,R,R-DAC-PU在高温 (170°C) 下,在应力 (0.1MPa) 下显示出最小的应变变化 (3.5%).
- 这两种PU配置都通过尿素键交换反应成功回收.
- 与cis细分市场相比,DFT计算证实了跨细分市场的更强,更短的键.
结论:
- 胺链延长剂的立体化学对于定制PU特性至关重要.
- 超立体化学可以提高机械性能和抗爬能力.
- 晶体立体化学改善了可加工性和弹性.
- 开发的PU是可回收的,为热材料提供可持续的解决方案.
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