Enhanced force transmission to mechanophores is demonstrated in polymer nanocomposite materials. Spiropyran (SP) mechanophores that change color and fluorescence under mechanical stimuli are functionalized at the interface between SiO₂ nanoparticles and polymers. Successful mechanical activation of SP at the interface is confirmed in both solution and solid states. Compared with SP‐linked in bulk polymers, interfacial activation induces greater conversion of SP to its colored merocyanine form and also significantly decreases the activation threshold under tension. Experimental observations are supported by finite element simulation of the interfacial stress state. The interfacial force‐focusing strategy opens a new way to control the reactivity of mechanophores and also potentially indicates interfacial damage in composite materials.

中文翻译：

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机械力连接的纳米复合材料的界面力集中效应

在聚合物纳米复合材料中已证明了向机械载体的增强的力传递。在机械刺激下改变颜色和荧光的Spiropyran（SP）机理在SiO ₂之间的界面处被官能化纳米粒子和聚合物。溶液和固态均可确认界面处SP的成功机械活化。与本体聚合物中连接的SP相比，界面活化引起SP转化为其有色花菁形式的转化率更高，并且在张力作用下还大大降低了活化阈值。实验观察得到界面应力状态的有限元模拟的支持。界面力集中策略为控制机械力的反应性开辟了一条新途径，也潜在地表明了复合材料中的界面损伤。