Reconfigurable and NIR-responsive shape memory polymer containing bipheunit units and graphene

A series of near-infrared (NIR)-responsive shape memory polymers based on biphenyl epoxy (BPEP/GR) were prepared by mixed amine thermal curing and photocuring with an iodized salt photoinitiator and aromatic ferrocene photosensitizer (IOD/FC) initiator. Differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and tensile test results indicated that the addition of graphene to a biphenyl-containing epoxy resin matrix led to improvements in the transition temperature, strength, and shape memory properties. Shape recovery could be completed within a few seconds by NIR irradiation due to the high photothermal conversion efficiency of graphene. NIR laser irradiation promoted the activation and recombination of biphenyl units due to local heating. Thus, a reconfigured shape was obtained. This new reconfiguration method is expected to help realize the important application of BPEP/GR composites in the field of intelligent soft robots.