分子捕获键和在聚合物机械化学中的反哈蒙德效应
Sai Sriharsha M Konda1, Johnathan N Brantley, Bibin T Varghese
1Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas 78712, USA.
Journal of the American Chemical Society
|August 3, 2013
概括
机械力可以抑制聚合物中的化学反应,这与传统的聚合物机械化学相反. 这一发现使得能够通过通过施加应力控制反应性来设计新的机械响应材料.
科学领域:
- 聚合物机械化学 聚合物机械化学
- 计算化学是一种计算化学.
- 材料科学是一种材料科学.
背景情况:
- 聚合物机械化学传统上使用机械力来加速反应.
- 理论模型表明,机械力也可以抑制反应性.
- 机械体是对机械应力有反应的化学单元.
研究的目的:
- 用计算方法研究六种机械体的机械反应性.
- 探索通过机械扰动抑制化学反应的潜力.
- 分析机械激活中反哈蒙德效应的发生率.
主要方法:
- 在六个机械上进行了电子结构计算.
- 计算模型是为了预测机械反应性而开发的.
- 实验研究是为了验证理论预测而进行的.
主要成果:
- 拉力可以减弱 (抑制) 机械化学现象.
- 简单的计算模型可以指导新机械响应材料的设计.
- 反哈蒙德效应在多原子分子的机械激活中普遍存在.
结论:
- 机械力提供了一种途径来抑制,而不仅仅是加速,聚合物中的化学反应.
- 计算建模是设计具有可调整机械反应的材料的宝贵工具.
- 了解反哈蒙德效应是控制机械化学过程的关键.
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