Gel Characteristics of Polyaniline and Its Anomalous Doping Effect

Abstract
Polyaniline gel has been prepared from soluble polyaniline. Remarkable shrinkage of the gel has been observed upon increase of the concentration of water in N-methyl-2-pyrrolidone. However, the temperature dependence of the volume of polyaniline gel is anomalous. Shrinkage of the volume of the gel has also been observed upon acid doping. On the contrary, the volume was expanded by iodine doping. These characteristics are discussed in terms of intermolecular hydrogen bonding.