ENHANCED PROPERTIES OF PVDF COMPOSITES BY ACTIVE PHASE SILANIZATION

Abstract

0.94[(Bi0.5Na0.5)TiO3]-0.06BaTiO3/polyvinylidene fluoride flexible composite films were prepared by the hot-pressing method. Surface modification of active phase particles was performed using two coupling agents, namely, (3- aminopropyl)triethoxysilane (APTES) and dodecyl triethoxysilane (DDTES) to enable good adhesion of active phase particles with the polymer matrix. The highest amount of electroactive PVDF β- phase was formed in APTES-modified samples while in DDTES samples mainly γ- phase was formed. Dielectric permittivity values and dielectric losses decreased for silanized samples due to reduced tension at the interface between particles and polymer. Strong intermolecular interaction between the PVDF chains and the APTES-modified particles led to enhanced breakdown strength of these samples. After the polarization of films, energy harvesting potential was evaluated for all samples. The highest voltage output of ~ 15 V and power ~ 225 μW were obtained for a single APTES-modified harvester [1-2].