Carbon or Barium Titanate Reinforced Epoxy Resin Nanocomposites: Dielectric, Thermomechanical and Functional Behaviour

Different nano-sized forms of carbon and ceramic barium titanate nanoparticles are used as epoxy reinforcements, resulting in composites with improved dielectric and thermo-mechanical properties. The carbon fillers used are carbon black, vapor grown carbon fibers and exfoliated graphite nanoplatelets. Electrical characterization of the composites was conducted by means of broadband dielectric spectroscopy, while viscoelastic properties were determined via dynamic mechanical analysis and the systems' morphology was investigated by means of scanning electron microscopy. Composite systems exhibit relaxations arising from both the polymer and the reinforcing phases. The incorporation of exfoliated graphite nanoplatelets appears to be beneficial to both dielectric and mechanical performance. Finally, the energy storing efficiency of the composites is examined as a function of the temperature, the frequency of the applied field, the type and the amount of the employed filler.