Dielectric spectroscopic analysis of polyvinyl chloride nanocomposites loaded with Fe 2 O 3 nanocrystals

Iron oxide (α‐Fe 2 O 3 ) nanocrystals powder was successfully synthesized via the sol‐gel method. The microstructural examination of the synthesized nanocrystals confirmed the formation of α‐Fe 2 O3 (hematite) structure using X‐ray diffraction and Fourier transform infrared. The synthesized nano‐hematite powder with different weight percentage up to 5 wt% was introduced to polyvinyl chloride (PVC) to fabricate PVC/Fe 2 O 3 nanocomposites using the solution‐cast technique. The dielectric spectroscopic analysis for the investigated samples has been studied at room temperature and at different temperatures up to 120°C. The real part of the permittivity (ε ′ ) exhibited a significant dependence on filler concentrations throughout whole temperature range. However, the dependency of both of the loss tangent ( tanδ ) and AC conductivity ( σ ac ) on filler concentrations is more pronounced at temperatures higher than room temperature. The obtained values of tan δ for the investigated nancomposites referred to the α‐relaxation around 70°C, which is close to glass transition temperature of the investigated PVC. The dependency of the dielectric strength on Fe 2 O 3 nanofiller concentration was observed with enhancement in the dielectric strength reach to 20.5% for PVC/0.7 wt% Fe 2 O 3 nanocomposite higher than the recorded value for the pristine PVC.