Number: 1999-024-1-400
Title: Polyaniline: Recommendations for preparation of conducting
polymer and its colloidal form
Task Group
Chairman: J. Stejskal
Members: S. P. Armes,
G. K. Elyashevich,
N. Gospodinova,
M. Helmstedt, J.
Janca, I. Krivka,
P. Mokreva, J.
Prokes, A. Riede,
E. Rozova, I.
Sapurina, T.V.
Shishkanovo, M. �pirkova,
T. Sulimenko, L.
Terlemezyan, and E.
Tobolkova
Completion Date: 2002 - project completed
Objective:
Recommendations for the preparation of conducting polymer, polyaniline,
and its colloidal form having defined structure and physicochemical
properties.
Description:
Electrically conducting polymers represent an emerging group of
new materials with non-conventional properties. Polyaniline is a typical
example of such a polymer. About 400 papers on polyaniline or its derivatives
have been published annually in recent years (according to Current Contents,
440 in 1995, 335 in 1996, 485 in 1997, and 487 in 1998).
Polyaniline exists in a variety of oxidation and protonation forms.
The various reaction conditions can lead to products with widely varying
chemical, macromolecular and supramolecular structures.
Conducting polymers often serve as active components in composite materials.
Their properties should be defined and known. The design of a preparation
protocol, which would yield a conducting polymer with guaranteed properties,
is desirable.
It is proposed to carry out the polymerization of aniline under various
reaction conditions (temperature, acidity), at least 3 times in each
case, at at least 5 independent research laboratories. The polyaniline
samples will be characterized with respect to both their structure (elemental
composition, molar mass, degree of crystallinity) and properties (conductivity,
density). The results then will be evaluated with respect to the reproducibility
of polymerizations on local and international scales.
A similar study, oriented on the preparation of colloidal forms by
dispersion polymerization of aniline will follow. A water-soluble polymer,
like poly(N-vinylpyrrolidone), will be used as a steric stabilizer.
The microparticle size and uniformity, colloidal stability, and other
properties will be investigated at this stage.
Progress:
59 samples of a conducting polymer, polyaniline, have been prepared
by using standard polymerization conditions in various institutions
(9 participants from 5 laboratories in 5 countries). An additional 28
polyanilines have been synthetized under modified reaction conditions.
The electrical conductivity of all samples was evaluated and compared.
Project completed - IUPAC Technical Report published in Pure
Appl. Chem.
74(5), 857-867, 2002.
The part of the project concerned with colloidal polyaniline dispersions
is in progress.
> See continuing project
Last update: 26 June 2002
<project announcement published in Chem.
Int.
22(5) 2000>