用光和热触发的可逆线性循环拓转换带有基末组的远程聚合物
Takuya Yamamoto1,2, Sakyo Yagyu1, Yasuyuki Tezuka1
1Department of Organic and Polymeric Materials, Tokyo Institute of Technology , O-okayama, Meguro-ku, Tokyo 152-8552, Japan.
Journal of the American Chemical Society
|February 27, 2016
概括
这项研究显示了使用光或热的可逆聚合物拓转换. 聚合物可以在线性和循环形式之间切换,对于较低的分子重量更快的转换.
科学领域:
- 聚合物化学
- 材料科学
- 超分子化学
背景情况:
- 控制聚合物拓对于先进的材料特性至关重要.
- 开发响应刺激的聚合物可以实现动态材料设计.
- 光化学反应可以精确控制聚合物转化.
研究的目的:
- 研究聚合物的可逆线性循环拓转换.
- 探索分子重量和终端组化学对这种转换的影响.
- 证明光和热能是拓变化的触发因素.
主要方法:
- 带有 antra 或 coumarinyl 末端组的电聚合物的合成.
- 光化学反应 (365nm和254nm的紫外线辐射) 诱导循环和线性化.
- 用热处理 (150°C) 将循环聚合物恢复到线性形式.
- 使用核磁共振 (NMR),大小排除染色学 (SEC) 和矩阵辅助激光消化/离子化飞行时间质谱法 (MALDI-TOF MS) 的表征.
主要成果:
- 成功合成了聚乙烯氧化物和聚甲) 带有基末端的远程分子.
- 在水性和有机介质中显示出高效的光诱导聚合物 (Ant-CO2-PEO) 循环.
- 显示了循环聚合物的定量热逆转到它们的线性状态,证实了可重复性.
- 观察到氨基终结聚合物 (Cou-PEO) 的溶剂依赖循环,突出显示了疏水相互作用的作用.
结论:
- 可逆线性循环拓转换在性和性聚合物中都是可行的.
- 循环的效率取决于聚合物分子量,终端组化学和溶剂环境.
- 光和热是可逆拓切换的有效触发器,为动态聚合物系统开辟了道路.
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