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Reversible thermochromism in violet-phase polydiacetylene derivatives triggered by ultraviolet photopolymerization
1School of Chemistry and Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China. chenluhe@njust.edu.cn.
Abstract:
A tetraphenylethylene (TPE)-functionalized diacetylene monomer undergoes direct photopolymerization to form violet-phase polydiacetylene (PDA) under 254 nm UV irradiation, not occurring conventional blue-phase formation. Steric constraints from the bulky TPE units force backbone distortion. The resulting polydiacetylene exhibits reversible violet-to-red thermochromism at 69 °C.
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