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Photoinduced Reversible Solid-to-Liquid Transitions for Photoswitchable Materials
Wen-Cong Xu1, Shaodong Sun1, Si Wu1
1CAS Key Laboratory of Soft Matter Chemistry, Hefei National Laboratory for Physical Sciences at the Microscale, Anhui Key Laboratory of Optoelectronic Science and Technology, Department of Polymer Science and Engineering, University of Science and Technology of China, Jinzhai Road 96, Hefei, 230026, China.
Angewandte Chemie (International Ed. in English)
|February 10, 2019
Summary
Certain azobenzene compounds undergo reversible solid-to-liquid transitions when exposed to light. This photoinduced phenomenon offers potential for advanced materials in various applications.
Area of Science:
- Materials Science
- Photochemistry
- Polymer Chemistry
Background:
- Conventional heating/cooling drives reversible solid-to-liquid transitions.
- Athermal photochemical processes offer an alternative mechanism for inducing such transitions.
Purpose of the Study:
- To review azobenzene compounds exhibiting photoinduced reversible solid-to-liquid transitions.
- To discuss the mechanisms, design principles, and applications of these materials.
Main Methods:
- Investigated azobenzene compounds with photoswitchable trans-cis isomerization.
- Analyzed melting points (Tm) and glass transition temperatures (Tg) of azobenzene isomers.
- Explored light-induced transitions based on isomer-specific thermal properties.
Main Results:
- Azobenzene compounds can undergo reversible solid-to-liquid transitions triggered by light.
- The trans and cis isomers possess distinct thermal properties (Tm, Tg).
- Photoinduced transitions occur when isomer thermal properties bracket room temperature.
Conclusions:
- Azobenzene compounds offer a light-controlled pathway for reversible solid-to-liquid transitions.
- Potential applications include healable coatings, adhesives, and advanced printing techniques.
- Further research is needed to address remaining challenges in the field.
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