光化学反应的机械化学调节
Xiaoran Hu1, Molly E McFadden1, Ross W Barber1
1Division of Chemistry and Chemical Engineering , California Institute of Technology , Pasadena , California 91125 , United States.
Journal of the American Chemical Society
|October 20, 2018
概括
我们开发了一种机械化学关闭的光开关, 这使得聚合物在受到压力后可以改变颜色,这对于记录材料历史非常有用.
科学领域:
- 材料科学
- 摄影化学
- 聚合物化学
背景情况:
- 照片交换依赖于光来改变分子状态.
- 控制光化学反应与外部刺激如机械力是一个挑战.
- 现有的光开关缺乏机械响应.
研究的目的:
- 介绍和演示机械化学关闭的光交换.
- 设计一种能够应对机械压力的新型机械体.
- 通过机械激活来启动光色行为.
主要方法:
- 合成了一种新型机械,基于环胺-马利胺-迪尔斯-阿尔德的添加物.
- 将机械纳入聚合物矩阵中.
- 使用超声波诱导机械激活.
- 使用UV-Vis光谱学研究生成的二甲光开关的光异构化.
- 进行控制实验以确认热稳定性和机械起源.
主要成果:
- 超声波诱导的机械激活产生了二甲光开关.
- 光开关在曝光时显示无色和有色状态之间的可逆光异构.
- 环二烯- 马利胺添加物显示出热稳定性.
- 控制实验证实机械力, 而不是热量, 启动光色反应.
结论:
- 机械化学关闭的光交换是控制光化学反应的可行概念.
- 设计的机械孔成功地将机械输入转化为光色输出.
- 这项技术在压力传感和聚合物数据存储方面具有先进的应用潜力.
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