Electrical, optical and mechanical properties of PS/GNP composite films

In this study, the electrical, optical and mechanical properties of polystyrene (PS) thin films added graphene nanoplatelet (GNP) have been investigated. Surface conductivity (σ), absorbance intensity (A) and tensile modulus of these composite films have increased with increasing the content of GNP in the composite. The increase in the electrical and optical properties of the PS/GNP composite films has been interpreted by site and classical percolation theory, respectively. The electrical and the optical percolation thresholds of PS/GNP composite films were determined as Rσ = 23.0 wt.% and Rop = 13.0 wt.%, respectively. While the conductivity results have been attributed to the classical percolation theory, the optical results have attributed to the site percolation theory. The electrical (βσ) and the optical (βop) critical exponents were calculated as 2.54 and 0.40, respectively. The tensile modulus and the tensile strength of the PS/GNP composites increased with the increasing of GNP content in the PS. But, the toughness of the composites fluctuated with GNP addition.