Thermal responses of 3D-printed liquid crystal elastomer microcubes

Liquid crystal elastomers (LCEs) are stimuli-responsive materials allowing for pre-programed shape changing via precisely tailoring spatially variant orientation, or the director of the liquid crystal mesogens. A considerable challenge remains on fabricating micron-sized LCE structures with well-defined director patterns. In this work, we focus on 3D-printed LCE microcubes that are a few microns in size and have a uniform director at a pre-designable angle relative the cube side. We characterise their glass transition and nematic-to-isotropic transition temperatures and demonstrate that upon heating from the nematic phase at room temperature to the isotropic phase, the microcubes exhibit anisotropic shape changes depending on the director orientations with respect to the cube sides. These findings represent a step towards designing and fabricating LCE microstructures with programmable shape morphing.