POTASSIUM IODATE OXIDATION ROUTE TO POLYANILINE - AN OPTIMIZATION STUDY

A study of the bulk polymerization of aniline by potassium iodate in aqueous acidic media is reported. The effect of varying the solution acidity, reaction time and both the relative and absolute reactant concentrations on the polymer yield, chemical composition and compressed pellet conductivity of the polyaniline product was investigated. It is shown that substantial amounts of iodine are incorporated into the polymer, particularly at higher initial oxidant/monomer mole ratios. The chemical nature of the incorporated iodine species is complex but preliminary X-ray photoelectron spectroscopy studies suggest that several species are probably present. Partial removal of this iodine can be achieved by dedoping the polyaniline powders, indicating that at least some of the iodine is present as a dopant anion. The polyaniline powders were also characterized by scanning electron microscopy, differential scanning calorimetry, thermogravimetric analysis, and Raman spectroscopy.