Effect of different reaction parameters on the conductivity and dielectric properties of polyaniline synthesized electrochemically and modeling of conductivity against reaction parameters through regression analysis

The polyaniline (PAni) is prepared electrochemically from an aqueous solution of aniline and HCl in a single compartment electrochemical cell. Different PAni samples obtained by varying monomer concentration, acid concentration, applied potential, reaction time, and reaction temperature are subjected to conductivity and dielectric tests. The degree of crystallinity, d-spacing, interchain separation, and crystallite size are determined form X-ray analysis, the oxidation state is determined from infrared spectroscopy (MR) analysis, and the doping level is estimated from TGA analysis for all the PAni samples synthesized under different conditions. All these structural properties are correlated with electrical properties. The whole result reveals that all the aforementioned reaction parameters affect the structural properties, which in turn affect the electrical properties of PAni. The mathematical model correlations between conductivity and reaction parameters are established from the regression analysis for individual variables as well as for all the variables together. These relationships give the conductivity as an output when we input the value of reaction variables. The output obtained from the model relations found in well agreement with the experimental results under identical conditions. (c) 2007 Wiley Periodicals, Inc.