Novel high dielectric constant nanocomposites of polyaniline dispersed with γ‐Fe₂O₃ nanoparticles

Abstract

Abstract Novel nanocomposites of polyaniline dispersed with γ‐Fe 2 O 3 nanoparticles were prepared by the in situ polymerization of aniline in the presence of ammonium peroxysulfate as an oxidizing agent. Dielectric constants of the derived composites varied with the composition of γ‐Fe 2 O 3 present in the matrix. A maximum dielectric constant of ∼5500 was achieved when 10 mass % γ‐Fe 2 O 3 nanoparticles were present. Nanocomposites were characterized by X‐ray diffraction, Fourier transform infrared, scanning electron microscopy, and thermal analytical techniques. Conductivity increased marginally by increasing the amount of γ‐Fe 2 O 3 in the matrix. Dielectric constants increased 100–150 times compared to plain polyaniline matrix and were 20–40 times higher than that of γ‐Fe 2 O 3 nanoparticles. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1868–1874, 2005