Modification of structural, thermal, dielectric and dynamic mechanical properties of PVA using lead (II) titanate

Polyvinyl alcohol (PVA)/lead (II) titanate (PbTiO 3 ) composites were prepared using the casting method. X-ray diffraction (XRD), infrared, scanning electron microscope (SEM), thermogravimetric analysis, optical, dielectric, dynamic mechanical analysis (DMA) were investigated on samples. XRD pattern of PVA/PbTiO 3 composites indicates the semi-crystalline nature of PVA and proved that PbTiO 3 consists of well-resolved peaks indexed to the P4mm space group with tetragonal symmetry. UV–Vis spectroscopy suggests that the composite is very effective at shielding UV radiation due to the enhanced absorption capacity of PbTiO 3 in a polymer matrix. A coarse surface was obtained by the addition of PbTiO 3 that was examined by SEM. Thermal analysis results indicate that the thermal stability of PVA/PbTiO 3 composites is improved compared with the pure PVA. The dielectric constant, dielectric loss and AC electrical conductivity were measured up to 5 MHz. Decrease in dielectric constant and dielectric loss followed by constant values with frequency increase was observed. DC plateau of electrical conductivity followed by an increase occurs, which may be due to the hopping mechanism due to the presence of O-2p → Ti-3d. The observations of the DMA indicate that the addition of PbTiO 3 increases both the storage modulus and the glass transition temperature of the composites. Finally, we noticed an increase in the calculated activation energy in the relaxation process in the glass transition region for all PVA composites.