Fig. 1: MC-LCE composition and schematic of the programming and measuring process.

a MC-LCEs are comprised of a polymer network made from divinyl terminated main-chain monomers (1), polymer chain extenders (2) and crosslinked with five-point crosslinkers (3). MC-LCEs were synthesized as a bulk, polydomain system, from which cube-shaped samples were cut. Phase transition temperatures are based on ac calorimetry measurements performed in our previous study². b Programming of the sample is carried out by thermal cycling to and from the isotropic phase while maintaining a programming stress. The programmed shape can then be reset to the original geometry by another thermal cycle without an applied load. c For the experiments, the sample was shape-programmed in one direction and then measured from all three to yield the associated Young’s moduli, \({E}_{{||}}\) and \({E}_{\perp }\) with respect to the programming stress.