ACS applied materials & interfaces | 2019
Reprogrammable 3D Shaping from Phase Change Microstructures in Elastic Composites.
Abstract
Herein, we demonstrate reprogrammable 3D structures that assemble from elastic composite sheets made from elastic materials and phase change microparticles. By controlling the phase change of the microparticles by localized thermal patterning, anisotropic residual strain is generated in the pre-stretched composite sheets, and then triggers 3D structure assembly when the composite sheets are released from the external stress. Modulation of the geometries and location of the thermal patterns leads to complex 2D-3D shaping behaviors such as bending, folding, buckling and wrinkling. Due to the reversible phase change of the microparticles, these programmed 3D structures can later be recovered to 2D sheets once they are heated for reprogramming different 3D structures. To predict the 3D structures assembled from the 2D composite sheets, finite element modeling was employed, which showed reasonable agreement with the experiments. The demonstrated strategy of reversibly programming 3D shapes by controlling phase change microstructures in the elastic composites offers unique capabilities in fabricating functional devices such as a rewritable paper and a shape reconfigurable pneumatic actuator.