Design and development of graphene oxide/shape memory nanocomposite based on hexamethylene diisocyanate mixing segment

Abstract

AbstractShape memory polymers are remarkable materials renowned for their distinctive ability to fix and recover their original shape in response to specific stimuli. However, the lower shape fixity (SF) of conventional thermally triggered shape memory polyurethane (SMPU) has limited its broad application potential. This study investigates the transformative influence of graphene oxide (GO) nanofillers when incorporated into a linear diisocyanate‐based mixing segment SMPU (SMPU‐GO). The lower SF issue of SMPU is ingeniously addressed by leveraging the interactive properties of GO with the 4,4′‐methylene bis‐phenyl diisocyanate hard segment and the introduction of additional physical cross‐links via hexamethylene diisocyanate mixing segment. At 1 wt.% GO incorporation, the modulus increased by 178%, an 8% increase in tensile strength, while the elasticity was maintained. Excellent improvement in SF and shape recovery (SR) was attained at 1 wt.% GO incorporated SMPU, and the SMPU nanocomposite showed the highest SF (65%) and SR (100%) at 70°C temperature and 50% strain.