Polydimethylsiloxane-PbZr0.52Ti0.48O3 nanocomposites with high permittivity: Effect of poling and temperature on dielectric properties

摘要

Polydimethylsiloxane (PDMS)/lead zirconate titanate (PbZr0.52Ti0.48O3, PZT)-based nanocomposites with high dielectric constant (permittivity, k) are prepared through room temperature mixing. The effect of PZT loading on electrical and mechanical properties of the PDMS-PZT composites is extensively studied. It is found that there is significant increase in permittivity with PZT loading and decrease in volume resistivity. All the composites have low dielectric loss compared to permittivity value. It is observed that there is increase in permittivity and decrease in volume resistivity of composites after poling, which is due to the dipolar polarization. It is found that both permittivity (epsilon ') and alternating current conductivity (sigma(ac)) are increased with temperature at low frequency (1 Hz) and decreased with temperature at high frequency (1 MHz). The above composites are sensitive to external pressure and can be used as pressure/force sensor. The tensile strength and % elongation at break decreases with PZT loading, which is due to the nonreinforcing behavior of PZT ceramic. PZT particles distribution and dispersion in PDMS matrix are observed through field emission scanning electron microscopy, high resolution transmission electron microscopy, and atomic force microscopy/scanning probe microscopy. Thermal stability of composites increased with the PZT loading which is due to higher thermal stability of PZT particles compared to PDMS matrix. (c) 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47307.