Dispersion of expanded graphite as nanoplatelets in a copolymer matrix and its effect on thermal stability, electrical conductivity and permeability

Expanded graphite/polyacrylonitrile-co-poly (methyl methacrylate) (EG/PAN-co-PMMA) composites were prepared by the incorporation of EG at various concentrations (1, 2, 3, and 4%, w/w) into PAN-co-PMMA by an in situ emulsifier-free emulsion polymerization method. As-synthesized composites were characterized by UV/VIS and FT-IR, XRD, SEM, TEM and TGA. The thermal stability of the copolymer was significantly improved by the addition of EG. The oxygen permeabilities of the composites were substantially reduced and the electrical conductivities of the composites were significantly increased by increasing the EG content.