ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7
The role of acidity profile in the nanotubular growth of polyaniline
Elena N. Konyushenko, Miroslava Trchová, Jaroslav Stejskal, and Irina Sapurina
Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, 162 06 Prague 6, Czech Republic
Received: 27 May 2009 Revised: 10 August 2009 Accepted: 19 August 2009
Abstract: Conditions of polyaniline (PANI) nanotubes preparation were analyzed. Aniline was oxidized with ammonium peroxydisulfate in
0.4 M acetic acid. There are two subsequent oxidation steps and the products were collected after each of them. At pH > 3,
neutral aniline molecules are oxidized to non-conducting aniline oligomers. These produce templates for the subsequent growth
of PANI nanotubes, which takes place preferably at pH 2–3. At pH < 2, granular morphology of the conducting PANI is obtained.
High final acidity of the medium should be avoided in the preparation of nanotubes, e.g., by reducing the amount of sulfuric
acid which is a by-product. Reduction of the peroxydisulfate-to-aniline mole ratio was tested for this purpose in the present
study. Lowering of the reaction temperature from 20°C to −4°C had a positive effect on the formation of nanotubes.
Keywords: conducting polymer - polyaniline - nanotubes - aniline oxidation - silver
Full paper is available at www.springerlink.com.
Chemical Papers 64 (1) 56–64 (2010)