Molecular Modeling of Protonic Acid Doping of Emeraldine Base Polyaniline for Chemical Sensing Applications

摘要

A combined molecular mechanics and molecular dynamics simulation techniques has been used to modeling the protonic acid doping of emeraldine base polyaniline. The molecular model, which is capable of representing the polyaniline doping with the aqueous hydrochloric acid, was built by Monte Carlo method. The doping process is modeled by a scripted loop control simulation using a doping distance criterion. The radial distribution functions of doped emeraldine salt and the relationships including pK_a/pH and doping percentage/pH, were computed and compared with the experimental data with good agreement. This method contributes a novel molecular modeling approach to predict the pH dependence of conducting polymer in design and evaluation of chemical sensing materials.