Polyaniline/silver nanocomposite preparation under extreme or non-classical conditions

Polyaniline (PANI) and polyaniline/silver nanocomposites have been synthesized by sonochemical and ionizing radiation technique. These composite materials were obtained through sonication and gamma irradiation of an aqueous solution of aniline and silver nitrate at room temperature. The suggested mechanisms to explain the formation of these products are based on the fact that both methods produce hydroxyl radical (OH)-O-center dot and hydrogen radical H-center dot, which acts as an oxidizing agent for the polymerization process of aniline monomer and as reducing agent for silver ions, respectively. Spectroscopic. X-ray and scanning electron microscope (SEM) measures showed that polyaniline and silver nanoparticles of 40 nm of average diameter are obtained when ultrasonic technique is used whereas silver nanoparticles of 60 nm average, and highly fibrillar polyaniline network with diameter of 60 nm is obtained when gamma radiation is used. (C) 2008 Elsevier B.V. All rights reserved.