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The electrically‐directed, isothermal response of liquid crystal elastomers (LCEs) to an applied electric field is a compelling approach to realize spatially tailorable, sequence‐controllable, and high‐frequency deformation. The electromechanical response is facilitated by coating aligned LCEs with compliant electrodes. Upon application of an electric field, the electrodes attract and generate Maxwell stress. The directional difference in moduli for aligned LCEs produces directional deformation of the material and does not require mechanical bias or framing. Here, LCEs prepared from a newly reported thiol‐ene reaction are explored as DEAs with improved mechanical and dielectric properties. This report details that incorporating a difunctional liquid crystalline monomer composed of allyl ether functional groups reduces Young's modulus, increases the dielectric constant, and improves cyclic recovery compared to an analogous LCE prepared by thiol‐ene polymerization. Electrically‐induced, isothermal deformation of as much as 30% strain is reported. The facile chemistry and enhanced electromechanical response reported here may enable the functional integration of LCEs in applications such as robotics.

Liquid crystalline elastomers (LCEs) that retain the cholesteric phase (CLCEs) are soft, polymeric materials that retain periodic structure and exhibit a selective reflection. While prior studies have examined thermochromism in CLCEs, the association of temperature change and reflection wavelength shift has been limited to 1.4 nm °C⁻¹. Here, CLCEs with intra‐mesogenic supramolecular bonds are prepared to enhance tunability as well triple the rate (e.g., 4.8 nm °C⁻¹). Specifically, these materials incorporate liquid crystalline monomers based on dimerized oxy‐benzoic acid (OBA) derivatives. Increasing the concentration of the OBA comonomers increases the magnitude of red‐shifting thermochromism of the selective reflection. At and above a threshold concentration, the selective reflection in the CLCEs can disappear upon heating, analogous to on‐off “switching.” Further, the introduction of the supramolecular bonds within the CLCE enable mechanical programming and enhanced one‐time tunable thermochromism via a one‐way shape memory process. Accordingly, this research could enable functional use in low temperature sensitive optical elements, fail‐safe thermal indicators for food packaging, and smart window coatings.

Liquid crystalline elastomers (LCEs) are stimuli‐responsive materials capable of undergoing large deformations. The thermomechanical response of LCEs is attributable to the coupling of polymer network properties and disruption of order between liquid crystalline mesogens. Complex deformations have been realized in LCEs by either programming the nematic director via surface‐enforced alignment or localized mechanical deformation in materials incorporating dynamic covalent chemistries. Here, the preparation of LCEs via thiol‐Michael addition reaction is reported that are amenable to surface‐enforced alignment. Afforded by the thiol‐Michael addition reaction, dynamic covalent bonds are uniquely incorporated in chemistries subject to surface‐enforce alignment. Accordingly, LCEs prepared with complex director profiles are able to be programmed and reprogrammed by (re)activating the dynamic covalent chemistry to realize distinctive shape transformations.