We introduce the concept of mechanochemically gated photoswitching. Mechanical regulation of a photochemical reaction is exemplified using a newly designed mechanophore based on a cyclopentadiene-maleimide Diels-Alder adduct. Ultrasound-induced mechanical activation of the photochemically inert mechanophore in polymers generates a diarylethene photoswitch via a retro-[4 + 2] cycloaddition reaction that photoisomerizes between colorless and colored states upon exposure to UV and visible light. Control experiments demonstrate the thermal stability of the cyclopentadiene-maleimide adduct and confirm the mechanical origin of the "unlocked" photochromic reactivity. This technology holds promise for applications such as lithography and stress-sensing, enabling the mechanical history of polymeric materials to be recorded and read on-demand.

中文翻译：

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光化学反应的机械化学调节

我们介绍了机械化学门控光开关的概念。使用基于环戊二烯-马来酰亚胺 Diels-Alder 加合物的新设计的机械团来举例说明光化学反应的机械调节。超声波诱导的聚合物中光化学惰性机械团的机械活化通过逆向 [4 + 2] 环加成反应产生二芳基乙烯光开关，该反应在暴露于紫外线和可见光时在无色和有色状态之间发生光异构化。对照实验证明了环戊二烯-马来酰亚胺加合物的热稳定性，并证实了“解锁”光致变色反应的机械起源。这项技术有望用于光刻和应力传感等应用，使聚合物材料的机械历史能够按需记录和读取。