The Dielectric Properties and Thermal Conductivities of Epoxy Composites Reinforced by Titanium Dioxide

To improve the dielectric properties and thermal conductivities of epoxy resins (EP), titanium dioxide superfine powders with microspheres structure (S-TiO2) were prepared via a hydrothermal process based on the sodium dodecyl benzene sulfonate and hydroxyl silicate. The different content of S-TiO2 was then employed as modifiers to add into EP resin to prepare the S-TiO2/EP composites. The structure and morphology of the prepared S-TiO2 was observed by X-ray diffraction (XRD) and scanning electron microscopy (SEM), and influences of different addition of S-TiO2 on the thermal conductivity of S-TiO2/EP composites are researched, while their dielectric constant and dielectric loss are also studied. The results suggested that the reasonable content of S-TiO2 can endow the S-TiO2/EP composites with higher dielectric constant without excessive increase their dielectric loss even under the high frequency. Furthermore, the thermal conductivity of S-TiO2/EP are also be improved, which can be attributed to the good thermal conductivity of S-TiO2 itself and the thermal conductivity path formed by S-TiO2 inside the EP matrix.