During the course of chemical reactions, reactant molecules need to surmount an energy barrier to allow their transformation into products. The energy needed for this process is usually provided by heat, light, pressure or electrical potential, which act either by changing the distribution of the reactants on their ground-state potential energy surface or by moving them onto an excited-state potential energy surface and thereby facilitate movement over the energy barrier. A fundamentally different way of initiating or accelerating a reaction is the use of force to deform reacting molecules along a specific direction of the reaction coordinate. Mechanical force has indeed been shown to activate covalent bonds in polymers, but the usual result is chain scission.%大多数化学反应的进行，需要反应物越过一个能量障碍。通常所提供 的能量是热能、光能、压差或电势。现在，令很多化学家感到吃惊的 是，机械力也被列在其中。也就是说，对于一个化学反应来说，我们 可以把它“推”一把。在超声波的影响下，特殊设计的聚合物的重排 反应可以加快，反应通道会出现偏向，产生从纯粹热或光诱导反应不 能获得的产物。这些聚合物含有一种mechanophore，其位置在来自 拉伸流(extensional flow)的力最大的点上。除了为控制化学反应提 供新方法外，这项研究工作还会导致具有机械适应性的材料问世，如 能够产生一种信号来警告将要出现的损坏、进行结构改变以减慢损坏 速度、甚至自我修复的聚合物材料。封面图片：Benjamin Grosser， Imaging Technology Group，Beckman Institute, UIUC。
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机译：During the course of chemical reactions, reactant molecules need to surmount an energy barrier to allow their transformation into products. The energy needed for this process is usually provided by heat, light, pressure or electrical potential, which act either by changing the distribution of the reactants on their ground-state potential energy surface or by moving them onto an excited-state potential energy surface and thereby facilitate movement over the energy barrier. A fundamentally different way of initiating or accelerating a reaction is the use of force to deform reacting molecules along a specific direction of the reaction coordinate. Mechanical force has indeed been shown to activate covalent bonds in polymers, but the usual result is chain scission.%大多数化学反应的进行，需要反应物越过一个能量障碍。通常所提供 的能量是热能、光能、压差或电势。现在，令很多化学家感到吃惊的 是，机械力也被列在其中。也就是说，对于一个化学反应来说，我们 可以把它“推”一把。在超声波的影响下，特殊设计的聚合物的重排 反应可以加快，反应通道会出现偏向，产生从纯粹热或光诱导反应不 能获得的产物。这些聚合物含有一种mechanophore，其位置在来自 拉伸流(extensional flow)的力最大的点上。除了为控制化学反应提 供新方法外，这项研究工作还会导致具有机械适应性的材料问世，如 能够产生一种信号来警告将要出现的损坏、进行结构改变以减慢损坏 速度、甚至自我修复的聚合物材料。封面图片：Benjamin Grosser， Imaging Technology Group，Beckman Institute, UIUC。
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