Liquid crystal elastomers (LCEs) with intrinsic anisotropic strains are reversible shape‐memory polymers of interest in sensor, actuator, and soft robotics applications. Rapid gelation of LCEs is required to fix molecular ordering within the elastomer network, which is essential for directed shape transformation. A highly efficient photo‐cross‐linking chemistry, based on two‐step oxygen‐mediated thiol–acrylate click reactions, allows for nearly instant gelation of the main‐chain LCE network upon exposure to UV light. Molecular orientation from the pre‐aligned liquid crystal oligomers can be faithfully transferred to the LCE films, allowing for preprogrammed shape morphing from two to three dimensions by origami‐ (folding‐only) and kirigami‐like (folding with cutting) mechanisms. The new LCE chemistry also enables widely tunable physical properties, including nematic‐to‐ isotropic phase‐transition temperatures (
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A sophisticated machine learning framework was developed to design thermally robust shape memory vitrimers (TRSMVs) with superior recycling efficiency, an elevated
- Award ID(s):
- 1946231
- NSF-PAR ID:
- 10496342
- Publisher / Repository:
- https://pubs.rsc.org/en/content/articlelanding/2023/cp/d3cp03631f/unauth
- Date Published:
- Journal Name:
- Physical Chemistry Chemical Physics
- Volume:
- 25
- Issue:
- 43
- ISSN:
- 1463-9076
- Page Range / eLocation ID:
- 30049 to 30065
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract T N‐I), glassy transition temperatures (T g), and mechanical strains, without disrupting the LC ordering. -
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Abstract Liquid crystal elastomers (LCEs) with intrinsic anisotropic strains are reversible shape‐memory polymers of interest in sensor, actuator, and soft robotics applications. Rapid gelation of LCEs is required to fix molecular ordering within the elastomer network, which is essential for directed shape transformation. A highly efficient photo‐cross‐linking chemistry, based on two‐step oxygen‐mediated thiol–acrylate click reactions, allows for nearly instant gelation of the main‐chain LCE network upon exposure to UV light. Molecular orientation from the pre‐aligned liquid crystal oligomers can be faithfully transferred to the LCE films, allowing for preprogrammed shape morphing from two to three dimensions by origami‐ (folding‐only) and kirigami‐like (folding with cutting) mechanisms. The new LCE chemistry also enables widely tunable physical properties, including nematic‐to‐ isotropic phase‐transition temperatures (
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