Gold nanoparticle/reduced graphene oxide hybrids for fast light-actuated shape memory polymers with enhanced photothermal conversion and mechanical stiffness

A fast light-actuated shape memory polymer (SMP) composite with greatly enhanced photothermal conversion and mechanical stiffness was prepared by incorporating gold nanoparticle/reduced graphene oxide (AuNP-RGO) hybrids into cross-linked poly(epsilon-caprolactone) (PCL). The AuNP-RGO hybrids with AuNPs uniformly anchored on RGO sheets were obtained in a water/n-butylamine system. Due to the homogeneous dispersion of AuNP-RGO in PCL matrix and the synergistic effect of photothermal conversion, the AuNP-RGO hybrids imparted the PCL with fast near-infrared (NIR) light-actuated shape recovery effect, and the light-actuated shape recovery speed could be accelerated via the increase of AuNP loading on RGO sheets. Moreover, the SMP composites possessed high shape recovery stress due to the incorporation of AuNP-RGO, thus they could be used as heavylift actuators. This SMP composites with enhanced light responsivity and mechanical properties are believed to have great potential in many fields such as light energy harvesting and remote-controlled actuators.