Synthesis and Dielectric Behavior of a New Two-Phase Percolative BaTiO3-Cu/Polyimide Composite
The chemical reduction method was used to deposit copper nanoparticles (about 20nm) on the surface of the barium titanate (BT, r=50nm). Then the dielectric properties and the mechanism of BaTiO3-Cu/polyimide composite were studied. The results showed that the effective dielectric permittivity of the composite with 60 wt% of BT-Cu (less than 13.00 wt% of copper) fillers was greater than 120, and the dielectric loss of which was lower than 0.025. Due to very low dielectric loss, so this composite was a two-phase composite material, different from the three-phase composite (metal-ceramics-poly). It was concluded that copper nanoparticles were deposited on the surface of the BT nanoparticles by chemical bond. Owing to good dielectric properties of as-prepared composite, such new two-phase composites had a potential to become the most important ferroelectric material.