MgTiO3/polystyrene composites with low dielectric loss

Composites of MgTiO3 filler dispersed inside polystyrene (PS) matrix were prepared by extrusion method and hot-molding technique. Effects of particle size of MgTiO3 on the dielectric properties of MgTiO3/PS composites were investigated at microwave frequencies. With increasing of MgTiO3 content, the apparent density of the composites was increased, while the relative density was decreased due to the increase of porosity, which induced the increase of dielectric loss (tan δ) of the composites. The tan δ of the composites was also affected by the mixture ratio of MgTiO3 with different particle sizes. The dielectric constant (K) and temperature coefficient of resonant frequency (TCF) of the composites with MgTiO3 content and particle size were also discussed.