Investigation of the effect of electron beam irradiation on tensile, thermal and gas barrier properties of graphene nanoplatelet loaded thermoplastic nanocomposite films

Abstract

Packaging materials based on lightweight and flexible thermoplastic/graphene composite films are gaining popularity in both the academic and industrial sectors. In this research work, graphene nanoplatelet (GNP) of 1–5 wt% was integrated into linear low density polyethylene (LLDPE) by employing melt compounding technique at 160 °C to produce flexible composite films. The LLDPE/GNP nanocomposite films were irradiated with doses up to 50 kGy using a 2.5 MeV electron beam accelerator in air at ambient temperature. The uniform distribution of GNP in the thermoplastic matrix obtained from FESEM analysis improved the samples' mechanical characteristics. As the GNP concentration in the LLDPE matrix increases, both the thermal stability and impermeability qualities (oxygen and water vapor) get significantly improved. Electron beam irradiation of film samples further enhances the physico-mechanical, thermal and gas barrier properties compared to non-irradiated composite films and neat LLDPE film. The tighter connections between graphene and LLDPE chains as well as the development of cross-linked networks by E-beam irradiation are responsible for the improved performance properties. Therefore, GNP incorporation as well as electron beam irradiation of thermoplastic nanocomposite films could be a viable alternative for producing high-performance and high-barrier flexible LLDPE/GNP composite films for packaging applications.