Actuation of Liquid Crystalline Elastomers at or Below Ambient Temperature.

TLDR: In this article , a materials chemistry to prepare liquid crystal elastomers (LCE) via thiol-Michael/thiol-ene reactions that actuate at or below ambient temperature was introduced.

Abstract: Liquid crystal elastomers (LCE) are an emerging class of material actuators. LCE undergo macroscopic dimensional changes when subject to a stimulus. The large stimuli-response of LCE is associated with thermotropic disruption of order. Historically, comparatively high temperatures are required to disrupt orientation in LCE to achieve meaningful work output. Here, we introduce a materials chemistry to prepare LCE via thiol-Michael/thiol-ene reactions that actuate at or below ambient temperature. Alignment was imparted to the LCE by mechanical alignment and 3-D printing. The LCE materials detailed here achieve strains of 40% with a maximum deformation rate of 6.5%˚C -1 . The functional utility of the tunability of the thermotropic response of these materials is illustrated in reconfiguration triggered via body heat and sequential actuation of a multi-material element.