ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

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

E-mail: elenak@imc.cas.cz

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.

DOI: 10.2478/s11696-009-0101-z

Chemical Papers 64 (1) 56–64 (2010)