了解化环环环的结构-聚合热力学关系,以开发可化学回收的聚合物
Junfeng Zhou1, Devavrat Sathe1, Junpeng Wang1
1School of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio 44325, United States.
Journal of the American Chemical Society
|January 5, 2022
概括
化学可回收的聚合物提供了一个可持续的解决方案. 这项研究探讨了循环 octene 单体中的化环如何影响聚合热力学,使得循环材料使用可调节的脱聚合.
科学领域:
- 聚合物化学
- 材料科学
- 可持续化学
背景情况:
- 聚合物的化学回收是解决塑料可持续性挑战的关键.
- 设计可回收的聚合物需要了解聚合和脱聚合的单体结构热力学关系.
- 化环的环单体在化学回收过程中被探索.
研究的目的:
- 研究化环的环单体的结构聚合热力学关系.
- 确定化环结构如何影响聚合和.
- 评估替代剂对产生的聚合物的脱聚合行为和热力学特性的影响.
主要方法:
- 合成和特征化循环 octene 单体与合的 trans-cyclobutane, trans-cyclopentane 和 trans-five-membered 循环 acetals.
- 使用测定和变化的技术对聚合物的热力学分析.
- 在各种单体度下测量上限温度 (Tc).
- 研究双质替代剂对化循环乙单体的影响.
主要成果:
- 在循环 octene 单体中合的四个和五个环减少了环应变.
- 聚合的度变化范围为-2.1到-3.3千卡mol-1 .
- 由于低变化 (-2.7 到 -5.0 卡莫尔-1 卡莫尔-1),天花板温度范围很广 (330 680 °C).
- 循环乙烯化循环的远程双替代剂可显著降低天花板温度300°C左右.
结论:
- 循环 octene 单体中的化环的结构极大地影响了聚合热力学和天花板温度.
- 观察到的远程宝石取代效应提供了一种增强脱聚合和调整聚合物的策略.
- 这些发现有助于为循环经济设计下一代化学可循环聚合物.
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