Preparation of core-shell particles having poly(aniline) shell and their application

Core-shell particles whose shells are composed of poly(aniline) were prepared by seeded oxidation polymerization of aniline. The morphology of the core-shell particles depended on the kind of seed particles and on the ratio of HCl to aniline monomer. Seeded polymerization of aniline using hydrophilic seed particles in highly acidic medium resulted in the formation of raspberry-structured particles, whereas seeded polymerization on hydrophobic seeds in neutral medium gave particles with a flat surface. The morphology affected the conductivity of packed particles because of the slight chance for contacts of poly(aniline) with neighboring particles. Poly(aniline) particles adsorbed silver ions and reduced then to silver on their surfaces. Thus the obtained particles exhibited high ability to catalyze the reduction of p-nitrophenol by sodium borohydride.