A multifunctional hydrogel with high conductivity, pH-responsive, thermo-responsive and release properties from polyacrylate/polyaniline hybrid

Polyacrylate/polyaniline (PAC/PANI) hybrid was synthesized by a two-step aqueous polymerization method, which aniline monomer was absorbed in the network of polyacrylate and followed by a polymerization reaction between aniline monomers. The PAC/PANI hydrogel possessed a conductivity of 2.33 mS cm(-1). A conduction mechanism with charge carriers (protons) hopping along the polyaniline chain was suggested. The PAC/PANI hydrogel had predominant pH- and thermo-sensitive properties. The hydrogel showed two sharp water adsorbed peaks at pH 4-6 and pH > 12. The swelling sensitive temperature of PAC/PANI hydrogel was about 30 degrees C. PAC/PANI hydrogel possessed loading and releasing properties. The release obeyed all anomalous mechanism. (C) 2007 Elsevier Ltd. All rights reserved.