Reinforcing effect of functionalized graphene nanoplatelets in palm kernel polyol based polyurethane composite

Abstract

Shape memory polyurethane-based palm kernel oil (SMPU based PKOp) has been shown to possess good shape memory properties. However, SMPU based on vegetable oil bear poor mechanical properties, thus enhancing mechanical properties using reinforcement, such as graphene nanoplatelets (GNP) is favorable in term of performance and cost. Nevertheless, the high viscosity of the polymer and high surface energy of GNP are obstacles in achieving a good composite. Therefore, in this research, a series of acid functionalization process was conducted to enhance the distribution of GNP in SMPU matrix, as well as the effects of functionalized GNP on the mechanical and shape memory properties of PKOp based SMPU were investigated. Functionalized GNP-based SMPU composite (PU-F) reached maximum tensile strength at 1wt% of functionalized GNP, which is 150% higher compared to that of neat SMPU while tensile strain at break increased 1590% than that of neat SMPU at 0.25wt% functionalized GNP. However, the shape fixity was almost similar to that of pristine SMPU and all the composite samples exhibited 100% shape recovery.