Effect of loading fraction of three-dimensional graphene foam (3D-C) on thermal, mechanical, and shape memory properties of 3D-C/SMP composite

Abstract

Here, we have studied the effect of loading fraction of 3D-graphene (3D-C) on the properties of epoxy-based shape memory polymer (SMP). 3D-C has already been proven to be an effective filler to improve the thermal conductivity, resulting in increased shape transformation efficiency of the SMP. We prepared a series of 3D-C/SMP composite with different volume fractions of 3D-C and compared their thermal, mechanical, and shape memory properties. We observed that as the 3D-C content increases, the thermal conductivity of the composite increases along with shape transformation performances. However, interestingly, in conflict with typical nanofillers, we observed that the mechanical strength decreases at higher loading fraction due to the obstruction of polymer chains by interconnected branches. Hence, to leverage the extraordinary improvement of thermal conductivity by 3D-C, a careful design based on the amount of loading is essential to obtain a balance between thermal conductivity, mechanical strength and shape memory performance.