Flammability properties and electromagnetic interference shielding of PVC/graphene composites containing Fe3O4 nanoparticles

Abstract

The effects of combined graphene/Fe₃O₄ nanoparticles on the flame retardancy and smoke suppression of PVC were studied. The dispersion state of graphene in the PVC matrix was improved with the help of Fe₃O₄ nanoparticles. As a result, the peak values of heat release rate and smoke production rate measured by cone calorimetry were obviously decreased in the PVC/graphene/Fe₃O₄ composites. According to the results from TGA tests and structural characterization of residual char, the improved flame retardancy was partially attributed to the formation of a network-like structure due to the good dispersion state of graphene in the PVC matrix, and partially to the carbonization of degradation products of PVC catalyzed by Fe₃O₄ nanoparticles. In addition, ternary PVC composites showed higher mechanical properties than pure PVC. More importantly, the resulting material possessed both electrical and magnetic properties. As a result, the ternary composites showed favorable electromagnetic shielding efficiency in the X-band frequency region (8–12 GHz), due to the formation of conducting interconnected graphene-based networks in the insulating PVC matrix and the magnetic properties.