Novel polyaniline/PVDF/BaTiO3 hybrid composites with high piezo-sensitivity

Polyvinylidene fluoride (PVDF)–barium titanate (BaTiO3)–polyaniline (PANI) hybrid composites were prepared by conventional powder processing technique which exhibited remarkably high piezo-sensitivity. The effect of poling of these semi-insulating composites on their piezo-response was quite dramatic. Sensitivity factors of 3000 could be achieved for even small poling voltages as low as 180 V/mm. The synergistic effect was obtained only when all three components, viz. PANI, PVDF and BaTiO3 were present at certain proportion below percolation threshold in the composite. The results have been explained on the basis of charge storage in the piezo components due to the high fields generated, even for low external applied field, at the inter-granular sites between the semi-conducting polyaniline phase dispersed in the insulating matrix.