Dielectric spectroscopic analysis of polyvinyl chloride nanocomposites loaded with Fe2O3 nanocrystals

• Published in: Polymers for advanced technologies 2018-09, Vol.29 (9), p.2477-2485
• Main Authors: Mansour, Sh. A., Elsad, R. A., Izzularab, M. A.
• Format: Article
• Language: English
• Subjects: Chemical industry; dielectric breakdown strength; Dielectric strength; Fourier transforms; Glass transition temperature; Hematite; Iron oxides; loss tangent; Nanocomposites; Nanocrystals; permittivity; Polyvinyl chloride; PVC; Sol-gel processes; Spectroscopic analysis; Synthesis; Temperature; Temperature dependence; X-ray diffraction
• ISSN: 1042-7147; 1099-1581
• DOI: 10.1002/pat.4359

Iron oxide (α‐Fe2O3) nanocrystals powder was successfully synthesized via the sol‐gel method. The microstructural examination of the synthesized nanocrystals confirmed the formation of α‐Fe2O3 (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/Fe2O3 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 (σac) 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 Fe2O3 nanofiller concentration was observed with enhancement in the dielectric strength reach to 20.5% for PVC/0.7 wt% Fe2O3 nanocomposite higher than the recorded value for the pristine PVC.