Low loss high dielectric permittivity of polyvinylidene fluoride and KxTiyNi1-x-yO (x=0.05, y=0.02) composites

Homogeneous thick film (similar to 0.10 mm) of high dielectric K0.05Ti0.02Ni0.93O; abbreviated as KTNO/polyvinylidene fluoride (PVDF) composite has been prepared by hot-molding technique. The frequency and temperature dependent dielectric behavior of this composite has been studied by varying the KTNO volume fraction (f(KTNO)). Near the percolation threshold (f(KTNO)=0.40), a large enhancement of effective dielectric permittivity (epsilon(eff)similar to 400 which is 40 times higher than that of pure PVDF) with low loss (similar to 0.20 at 1 kHz) is observed. The experimental epsilon(eff) data have been fitted with different theoretical models and found to follow percolation theory successfully. Such a high epsilon(eff) and low loss flexible dielectric material appears to be suitable for technological applications. (c) 2010 American Institute of Physics. [doi:10.1063/1.3437633]