在网络中多环聚二甲基素的罗塔形成:从高分子量轴和轮部件构建"宏罗塔素"的一步
Minami Ebe1, Asuka Soga1, Kaiyu Fujiwara1
1Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo, 060-8628, Japan.
Angewandte Chemie (International ed. in English)
|July 17, 2023
概括
通过在网中捕获多循环聚二甲基酸酸来合成的宏基酸,显示出软材料的潜力. 这些新的结构提供了改进的阻尼性能,并作为非漂水添加剂.
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:
- 宏罗塔克桑为软材料应用提供了高度的结构自由.
- 宏罗素的合成,特别是在聚合物网络中,是一个尚未探索的领域.
- 聚甲基酸盐 (PDMS) 是多功能聚合物,具有形成网络的潜力.
研究的目的:
- 通过在网络中对多循环PDMS (mc-PDMS) 进行拓捕获来研究宏罗塔克桑的形成.
- 探索 mc-PDMS 结构 (周期单位数量,环大小) 对捕捉效率的影响.
- 评估基于mc-PDMS的宏罗塔克桑作为网中的添加剂的性能.
主要方法:
- 通过循环聚合,合成具有不同周期单位和环大小的mc-PDMS.
- 制备含有10-60%重量的mc-PDMS的网.
- 在网络中确定mc-PDMS捕获效率.
- 评估由此产生的宏罗他素聚合物复合材料的阻尼性能 (tan δ).
主要成果:
- 增加了循环单位和更大的环形大小的mc-PDMS在网络中被定量捕获,形成了宏观rotaxanes.
- 与多环形变体相比,单环形PDMS的捕获效率较低.
- 与裸体PDMS网络相比,使用60%重量MC-PDMS的网表现出增强的阻尼性能 (更高的tan δ).
结论:
- 多循环PDMS可以有效地被困在网中,形成宏观rotaxanes.
- 宏罗塔克桑具有作为非漂水添加剂的潜力,可以增强网络聚合物的性能.
- 这项研究提供了一个可行的合成途径,用于聚合物网络中的宏-罗塔xane形成.
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