Experimental Study and Kinetic Modeling of Aniline Polymerization

Polyaniline is a conducting polymer with a wide variety of applications. In the recent years, exploring the different avenues for the synthesis of polyaniline has gained immense popularity among the researchers. This study focuses on the experimental investigation and subsequent data modeling to determine the kinetics of chemical (oxidative) polymerization of aniline with ammonium persulfate as an oxidant in aqueous hydrochloric acid solutions at 277 K. The concentration of the polyaniline formed was determined using colorimetry. The effect of different initial concentrations of oxidant/monomer from 0.010–0.025 M on the rate of polymerization was observed. The polymerization kinetics at various initial oxidant to monomer mole ratios from 1–2.5 was also investigated. Using a well-established kinetic rate expression, the reaction rate constants were determined that best fitted the experimental data. Further, the polyaniline concentrations were predicted using the kinetic parameters with an absolute average relative deviation ranging from 4 to 17%.