Polymer-Graphene Nanoplatelets Nanocomposites: Properties and Applications

A review study is presented in relation to polymer/graphene nanocomposites. The research works have shown that the graphene can be considered as the strongest material and the hummer’s method is a suitable method for its production. Functionalization by chemical groups compatible with its matrix can enhance dispersion of the nanoparticles within it. The effect of graphene nanoplatelets on the isothermal and non-isothermal crystallization behavior, nucleation and crystal growth is explained. Several contradicting results including both increase and decrease in crystallinity have been reported. The change of electrical conductivity with the addition of graphene and method of determining percolation threshold are presented. The results showed a significant increase in electrical conductivity by incorporation of graphene nanosheets. The mechanical properties of nanocomposites including elastic modulus, elongation-at-break and tensile strength are reviewed. The reported results revealed that modulus increased due to higher modulus of nanoparticles and there was a contradictory result for tensile strength and elongation-at-break. Functionalization of nanosheets could increase the tensile strength of nanocomposites through stronger adhesion between filler and matrix. The thermal conductivity of these nanocomposites and the desirable method for measurement of thermal conductivity constant are discussed. The results showed that graphene nanoplatelets are less effective in enhancing thermal conductivity in comparison to electrical conductivity. The rheological properties of nanocomposites were affected by addition of nanosheets and the obtained rheological percolation threshold was different from the electrical one. The lower electrical percolation in comparison to rheological one means electrical threshold is obtained from direct contact of nanoparticles.