Modeling study on dielectric properties of graphene-doped polymer composites

A dielectric model of graphene-doped polymer composites is proposed based on the interfacial polarization theory, and the effect of graphene on the effective permittivity of the composites is described. The proposed model explains the interaction between graphene nanoplatelets and polymer matrix at the interfacial layer and calculates the local permittivity and the local electric field of the interfacial layer. With the control variable method, the influence of material properties in the dielectric model is analyzed. Compared with the traditional empirical model, the proposed dielectric model clarified the mechanism of the effect of the upper limit separation distance, the potential barrier height, the matrix layer conductivity, the graphene nanoplatelet sizes, and other factors on the effective permittivity. The effective permittivity of multiple binary and ternary dielectric composites is predicted. The validity of the proposed model is verified by comparing with the experimental values of samples and literature.