Dielectric property of ultrafine BaTiO3/epoxy composite

Ultrafine BaTiO₃ presents attractive dielectric properties. In this paper, BaTiO₃/epoxy composite samples were prepared with different ultrafine BaTiO₃ content of 1%, 10%, 20%, 30%, 40%, 50%, 60%, 75.8%, respectively. The dielectric and ferroelectric properties were investigated only from the view of powder characteristics. The results showed that two dielectric peaks in the temperature dependence curves of dielectric constant, and the second peak moved towards the higher temperature with frequency increasing. By comparing different conversion theories, Logarithm theory was thought to be the most reasonable for the situation we discussed. It is indicated that the interaction zone between BaTiO₃ particles and epoxy resin is formed and the surface effect plays an important role in dielectric relaxation phenomenon of ultrafine BaTiO₃ particles. In addition, the organic-inorganic composite might be a significant method to estimate the properties of ultrafine particles.