双线式滑环聚链网
Laura F Hart1, William R Lenart1, Jerald E Hertzog1,2
1Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States.
Journal of the American Chemical Society
|May 25, 2023
概括
具有移动交叉连接的机械互锁聚合物,如滑环聚链网,提供增强的性. 从这些网络中去除金属离子释放了链的流动性,并改善了弹性排水.
科学领域:
- 聚合物化学
- 材料科学
- 超分子化学
背景情况:
- 聚合物网络中的共价交联通常会导致由于结构不均而导致的脆弱性.
- 机械互锁聚合物 (MIP) 与移动交叉连接,如滑环网络 (SRN) 和多链网 (PCN),提供了更好的性和强度.
- 滑环多链网 (SR-PCN) 结合了SRN和PCN的特征,使其能够通过滑链环进行动态交叉连接.
研究的目的:
- 通过金属离子模板伪[3]rotaxane (P3R) 交叉连接器合成和研究滑环聚链网 (SR-PCN).
- 探索P3R与共价交叉连接器的比率变化的网络性能影响.
- 了解金属离子在控制交叉链的移动性及其对机械行为的影响.
主要方法:
- 使用无催化剂的氧化物/环添加聚合物合成SR-PCN.
- 将金属离子模拟的双线假[3]rotaxane (P3R) 作为移动交叉连接器与共价交叉连接器相结合.
- 合成的SR-PCN的机械性能测试,包括金属离子去除前后的研究.
主要成果:
- 金属离子有效地"锁定"伪[3]rotaxane环,导致与常规共价聚乙醇 (PEG) 凝相似的机械性能.
- 移除金属离子释放了连锁环的移动性,导致高频机械转换.
- 在没有金属离子的SR-PCN中,动态交联增强了聚合物链的松,并在较长的时间范围内加快了弹性排水.
结论:
- SR-PCN提供了一个可调节的平台,用于创建强大和动态的聚合物网络.
- 金属离子模板提供了一种可逆的方法来控制交叉连接的移动性和材料特性.
- 解锁的SR-PCN的动态性导致了更好的机械响应和流体传输特性.
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