Preparation and dielectric behaviors of thermoplastic and thermosetting polymer nanocomposite films containing BaTiO3 nanoparticles with different diameters

BaTiO3 (BT) nanoparticles with three kinds of diameters were synthesized by alkoxide route and then dispersed into a thermoplastic polyvinylidene fluoride (PVDF) and a thermoset polyimide (PI)) to fabricate the BT/PVDF and the BT/PI nanocomposite films. Effects of nanoparticle size and polymer matrix on the dielectric properties were studied by two different measurement procedures at frequencies from 10−2 Hz to 106 Hz. A significant discrepancy of dielectric behaviors between the BT/PVDF films and the BT/PI films was found. The roles of nanoparticles (size and crystal phase) and properties of polymers (chemistry and chain structure) are used to explain the difference in dielectric behaviors.