This paper describes the preparation, physical properties, and electric bending actuation of a new class of active materials—ionic liquid crystal elastomers (iLCEs). It is demonstrated that iLCEs can be actuated by low‐frequency AC or DC voltages of less than 1 V. The bending strains of the unoptimized first iLCEs are already comparable to the well‐developed ionic electroactive polymers. Additionally, iLCEs exhibit several novel and superior features, such as the alignment that increases the performance of actuation, the possibility of preprogrammed actuation patterns at the level of the cross‐linking process, and dual (thermal and electric) actuations in hybrid samples. Since liquid crystal elastomers are also sensitive to magnetic fields and can also be light sensitive, iLCEs have far‐reaching potentials toward multiresponsive actuations that may have so far unmatched properties in soft robotics, sensing, and biomedical applications.
- Award ID(s):
- 1808436
- NSF-PAR ID:
- 10382660
- Date Published:
- Journal Name:
- Micromachines
- Volume:
- 13
- Issue:
- 8
- ISSN:
- 2072-666X
- Page Range / eLocation ID:
- 1310
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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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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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/mi13081310
