Effects of Doping on Zeta Potential and pH of Polyaniline Colloidal Suspension

Abstract

Polyaniline (PANI) has successfully been prepared by chemical oxidation polymerization of aniline monomer. The prepared polymer was confirmed by XRD. The conducting form of PANI known as emeraldine salt (ES) through different concentrations of formic acid; 0.4 mmol/ L, 2mmol/ L, 6 mmol/ L, 8 mmol/ L, 10 mmol/ L, and 12 mmol/L is prepared from its insulating emeraldine base (EB) by levels of doping. The objective is to establish a correlation between the levels of doping, the zeta potential of the suspension. Positive zeta potential values (24.75, 27, 33.25, 36.75, 40.50, and 42) mV were obtained for the various PANI suspension. This showed the acquisition of positive charges by the PANI after doping. The observation was made that zeta potential values increases as formic acid concentration increased. This was correlated using UV/VIS spectra and electrophoretic coating with the polyaniline suspensions.