Facile fabrication of thermoresponsive polyurethanes including polycarbonate diol for enhanced shape-memory performance

Shape-memory polymers (SMPs) are materials that can recover its original shape from a temporarily fixed shape via external stimuli. Due to their shape-memory effects, SMP-based materials have been investigated for engineering applications in diverse areas. Among various SMP materials, shape-memory polyurethane (SMPU) has been extensively studied. Several studies have modified the morphology of SMPU matrices by incorporating various types of polyol components. In this study, we used two structurally distinct polyol substances, polycarbonate diol (PCD) and polyethylene glycol, to synthesize SMPU. The structures of the SMPU matrix could be tuned by varying the PCD mol% of the total polyol content. Shape-memory and mechanical properties are related to the interactions between the soft and hard segments of the SMPU. The permanent shape of the SMPU can be redefined by utilizing the shape-reconfigurable nature of transcarbamoylation. The redefined permanent shape can also be recovered from the temporarily deformed shape through shape-memory cycles.