来自单个机械体的强度依赖多色机械体
Molly E McFadden1, Maxwell J Robb1
1Division of Chemistry and Chemical Engineering , California Institute of Technology , Pasadena , California 91125 , United States.
Journal of the American Chemical Society
|July 9, 2019
概括
这项研究引入了一种新型的双纳夫索机械体,在机械力下改变颜色. 具有这种机制的聚合物表现出可预测的多色变化,使力感应应用成为可能.
科学领域:
- 聚合物化学
- 材料科学
- 机械化学
背景情况:
- 机械是对机械力进行化学变化的分子.
- 控制机械体的依赖力反应对于开发先进材料至关重要.
研究的目的:
- 合成和表征一个双纳夫托皮兰机械体.
- 研究含有这种机制体的聚合物的力依赖性机色行为.
- 为了建立应用力和颜色变化之间的关系.
主要方法:
- 聚合物的合成与一个中央bis-naphthopyran单位.
- 通过超声波进行机械激活.
- 通过改变聚合物链长度来调节施加的力.
- 对颜色变化的光谱分析.
- 密度函数理论 (DFT) 的计算.
主要成果:
- 证明了二纳夫托皮兰机械体的可见吸收力依赖的变化.
- 通过改变 merocyanine 产品的分布来实现渐变多色机色.
- 显示可预测的颜色变化与施加的力大小相关.
- 通过DFT计算和理论建模验证机械化学反应性.
结论:
- 双纳夫托皮兰机械体表现出可预测的,依赖力的多色机械体.
- 聚合物链长度有效调节对机械体施加的力.
- 这项工作为设计先进的力传感材料提供了基础.
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