Preparation and characterization of highly conducting polyaniline (PANI) doped with picric acid (PA) wasproved
with the help of various techniques. Elemental analysis, FTIR and XPS spectroscopic measurements confirm that the
PA operates as a protonating agent to induce the internal conversion of PANI emeraldine base (PANI-EB) to the PANI
emeraldine salt (PANI-ES) with the doping level 50%. Molecular modeling calculations (MMþ) showed that the optimum
geometric structure of 2PA:1PANI (energy 38.231388 kcal/mol, and gradient 0.065246).
The observed higher conductivity (r 150 S/cm) of PA-doped PANI film prepared at molar ratio 2PA:1PANI (EB)
isattributed to the change in the molecular conformation from coil to expanded coil-like. PA-doped PANI isthermally
unstable above 135
C and the thermal processing with other insulating matrix is not profitable but the solution
casting is highly promising. PA-doped PANI with acrylonitrile-butadiene-styrene copolymer has been fabricated and
showed the threshold value 4 wt.% of a conducting material. The reduced PA-doped PANI revealsan ability to store
electrical energy of about 110.43 Wh/kg in a condensed lightweight form. The immediate decoloration of the dark green
(kmax  815 nm) PANI after addition of 5.5 lg/ml KMnO4 in strong acid medium (pH 1.0, H2SO4, 40% DMF) isdue to
the highest oxidized form of PANI. Increasing the absorbance with increases in the KMnO4 concentration (lg/ml) at
385 nm has been successfully applied to the determination of trace amount (0.55 lg/ml) of Mn(VII) in a synthetic
solution.  2002 Elsevier Science Ltd. All rights reserved.