Elastomers and Composites

The Rubber Society of Korea (한국고무학회)
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Covalent Adaptable Liquid Crystal Elastomers Comprising Thiourea Bonds: Reprocessing, Reprogramming and Actuation

  • Lee, Jin-Hyeong (School of Chemical Engineering, Pusan National University) ;
  • Park, Sungmin (Advanced Materials Division, Korea Research Institute of Chemical Technology) ;
  • Kim, Yong Seok (Advanced Materials Division, Korea Research Institute of Chemical Technology) ;
  • Kim, Dong-Gyun (Advanced Materials Division, Korea Research Institute of Chemical Technology) ;
  • Ahn, Suk-kyun (School of Chemical Engineering, Pusan National University)
  • Received : 2022.06.08
  • Accepted : 2022.06.20
  • Published : 2022.06.30
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Abstract

In this work, we report a highly deformable covalent adaptable-liquid crystal elastomer (CA-LCE) comprising dynamic thiourea bonds that enable macromolecular network rearrangement at elevated temperatures. The exchange of chain network is verified through stress-relaxation analyses and follows Arrhenius-type behavior. The unique capability of rearranging the chain network in the CA-LCE provides useful properties, such as welding, melt reprocessing, and shape reprogramming, that cannot be achieved by the conventional LCE comprising permanent crosslinks. Reversible actuation is further demonstrated by reprogramming the polydomain CA-LCE into a monodomain via mechanical stretching at elevated temperatures.

Keywords

Acknowledgement

이 과제는 부산대학교 기본연구지원사업(2년)에 의하여 연구되었음.

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