A New Approach in the Dispersion of Graphene Nanoplatelets to Develop Shape Memory PLA Nanocomposites

A temperature sensitive shape memory polymer (SMP) system based on poly lactic acid (PLA) has been developed and the effect of graphene nanoplatelets (GNPs) on the shape memory properties was evaluated. Dispersion of GNPs in PLA was improved with the aid of a zwitterionic surfactant. It was found that surface modified GNPs (SMGNPs) were exfoliated and homogenously dispersed in the PLA matrix. Better dispersion of SMGNPs compared with GNPs was due to enhancement of the polymer-graphene interaction induced by the zwitterionic surfactant.The shape memory properties of nanocomposites were evaluated using thermo-mechanical analysis (TMA).The obtained results revealed that the shape memory performance of nanocomposite samples was affected by the degree of dispersion. Higher shape recovery of nanocomposite samples in comparison with that of neat PLA was obtained, which originated from their higher elastic glassy modulus. Up to 91% shape recovery was determined in nanocomposite samples containing SMGNPs