Mechanochromic polymers, that is, polymers sensitive to mechanical impact, promise great potential for applications in damage sensors. In particular, radical‐type mechanochromic polymers, which produce colored radical species in response to mechanical stress, may enable not only the visualization of mechanical stress, but also its quantitative evaluation by electron paramagnetic resonance analysis. Herein, a radical‐type mechanochromic polymer that exhibits a color change from white to green upon dissociation of a diarylbibenzothiophenonyl moiety at the mid‐point of a polystyrene chain is presented, and its mechanochromic behavior is examined. Mechanochromic materials that show a variety of colors (“rainbow colors”) in response to mechanical stress were prepared by simply mixing radical‐type mechanochromic polymers of primary colors.

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二芳基联苯并噻吩基解离后变绿的机械变色聚合物：彩虹机械变色的缺失部分

机械致变色聚合物，即对机械冲击敏感的聚合物，有望在损坏传感器中应用。尤其是，自由基型机械变色聚合物会响应机械应力而产生彩色自由基，不仅使机械应力可视化，而且能够通过电子顺磁共振分析对其进行定量评估。本文介绍了一种自由基型机械变色聚合物，该聚合物在聚苯乙烯链中点处的二芳基联苯并噻吩基部分解离时，颜色从白色变为绿色，并对其机械变色行为进行了研究。通过简单地混合基色的自由基型机械变色聚合物，就可以制备出能响应机械应力而显示多种颜色（“彩虹色”）的机械变色材料。