Theoretical and empirical models for predicting the thermal conductivity of polymer composites were summarized since the 1920s. The effects of particle shape, filler amount, dispersion state of fillers, and interfacial thermal barrier on the thermal conductivity of filled polymer composites were investigated, and the agreement of experimental data with theoretical models in literatures was discussed. Silica with high thermal conductivity was chosen to mix with polyvinyl-acetate (EVA) copolymer to prepare SiO 2 /EVA co-films. Experimental data of the co-films' thermal conductivity were compared with some classical theoretical and empirical models. The results show that Agari's model, the mixed model, and the percolation model can predict well the thermal conductivity of SiO 2 /EVA co-films.

To decrease the working temperature of the photovoltaic (PV) module in a solar PV system, an elastic co-film with excellent mechanical properties and adhesiveness, as well as high thermal conductivity, was fabricated based on the composition of a thermal-conductive alumina and ethylene vinyl acetate (EVA) polymer. The thermal conductivity of co-films with various particle sizes, dosage, surface properties, etc. of alumina was investigated by the laser scattering method. The scanning electron microscopic results showed that the co-film with 80 shares of submicron alumina in EVA polymer had a good interface binding. The thermal-conductive mechanism of the co-film was likewise discussed.