We report on the preparation method of nanostructured polyaniline (PANT) via the oxidation polymerization of aniline hydrochloride in the presence of an anionic surfactant. Two solvents with different polarities were used for the synthesis of PANT. The polymers were characterized with ultraviolet-visible, infrared, Raman, and X-ray photoelectron spectroscopy. The chemical structure derived from the optical characterization techniques and the electrical properties for the two polymers were almost identical. Transmission electron and scanning electron microscopy images revealed the morphological disparity between the PANIs synthesized under different solvent conditions: a microweb of nanofibers versus microtubes. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 116: 1587-1592, 2010