Cuboidal Deformation\nof Multimaterial Composites Prepared\nby 3‑D Printing of Liquid Crystalline Elastomers

Multimaterial 3-D printing (3DP) of isotropic (IsoE)\nand liquid\ncrystalline elastomers (LCE) yields spatially programmed elements\nthat undergo a cuboidal shape transformation upon heating. The thermomechanical\ndeformation of 3DP elements is determined by the geometry and extent\nof the isotropic and anisotropic regions. The synthesis and experimental\ncharacterization of the 3DP elements are complemented by finite element\nanalysis (FEA). Calculations emphasize that the cuboidal deformation\nof the myriad 3DP elements is a manifestation of local stress gradients\nimparted by local control of the material composition and anisotropy.\nVarying the rectilinear spatial distribution of the multimaterial\nelastomer composites produces complex, multistable states that provide\ninsights into how stress gradients drive multimaterial elastomer actuation.\nThe thermomechanical stimuli response of the multimaterial elements\nis explored as a tactile element.