Sol-gel synthesis of polyaniline/zirconia composite conducting materials

Polyaniline (Pani) conducting polymer was successfully synthesized by an emulsion polymerization of aniline monomer in the presence of dodecyl benzene sulfonic acid (DBSA). Consequently novel Pani.DBSA/zirconia composites (PDZr) were successfully synthesized by sol-gel technique. Structural and morphological characterization of PDZr composites were carried out using X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR), ultraviolet–visible spectroscopy (UV–Vis), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Upon incorporating zirconia the resulting composite material showed greater crystallinity. The FT-IR spectrum showed the characteristic peaks of Pani.DBSA shifted to higher wavenumbers. This suggests some interactions between zirconia network and Pani.DBSA polymer chains. TEM micrographs indicate morphological changes upon the formation of PDZr composites. The nanoparticles of Pani.DBSA formed rod-like structures in the resulting composite materials. A higher electrical conductivity was obtained when the PDZr composite was incorporated with 30 % weight of Zr(IV)-n-propoxide. Differential scanning calorimetry (DSC) measurements revealed two distinct glass transition temperature (Tg) for PDZr composite at low percentage of zirconia. Thermogravimetric analysis (TGA) results indicate that the maximum degradation temperature of the PDZr composites increased significantly to 484 °C.