Characterization and electrical behavior of polyaniline-poly-N-isopropylacrylamide-co-acrylic acid/alumina aqueous dispersions in the presence of dodecyl benzenesulfonic acid

Polymer composites containing polyaniline-poly-N-isopropylacrylamide-co-acrylic acid/alumina (PANI-PNA/Al2O3) were synthesized by chemical polymerization of aniline in an aqueous solution containing dispersed PNA/Al2O3 in the presence of dodecylbenzene sulfonic acid (DBSA) using different wt% of Al2O3 (5%, 10%, 20%, and 30%). The structure and morphology of the polymer matrix were identified by scanning electron microscope (SEM) and atomic force microscope (AFM). Thermal stability and an amended crystallinity were reasserted by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and X-ray diffraction (XRD), respectively. Chemical interaction of Al2O3 and PANI was characterized by XPS. The enhancement of the electrical conductivity in the temperature range 293-483 K shows a semiconducting behavior with a negative temperature coefficient of resistivity (TCR). In addition, the conductivity data are characterized by three different regions with small changing jerks with increasing temperature. (C) 2008 Elsevier Ltd. All rights reserved.