ISSN 1070-4272, Russian Journal of Applied Chemistry, 2016, Vol. 89, No. 2, pp. 200−205. © Pleiades Publishing, Ltd., 2016.
Original Russian Text © V.G. Kurbatov, N.A. Zakharova, N.V. Kochkina, E.A. Indeikin,
2016, published in Zhurnal Prikladnoi Khimii, 2016, Vol. 89, No. 2,
OF SYSTEMS AND PROCESSES
Aqueous Polyaniline Dispersions Stabilized by Polymeric
V. G. Kurbatov, N. A. Zakharova, N. V. Kochkina, and E. A. Indeikin
Yaroslavl State Technical University, Moskovskii pr. 88, Yaroslavl, 150999 Russia
Received November 2, 2015
Abstract—Aqueous dispersions of polyaniline were synthesized in the presence of various surfactants. Polyvinyl
alcohol and polymeric surfactants with various chain lengths of polyoxyethylene fragments served as stabilizers.
It was shown that it is advisable to use polymeric surfactants with side polyoxyethylene fragments to improve the
sedimentation stability of aqueous dispersions of polyaniline. It was found that the particle size distribution of
aqueous dispersions depends on the composition of the stabilizer used. Raising the pH value of aqueous disper-
sions to 8 makes it possible to substantially raise the sedimentation stability. The effect of a surfactant used to
stabilize the dispersed system on the electrokinetic potential was examined.
At present, the interest in development of new
materials based on electrically conducting polymers
and studies of processes underlying their synthesis is
steadily growing. Polyaniline (PANI) and polypyrrole
are typical representatives of electrically conducting
polymers. These compounds have found use in design
of amperometric sensors with increased sensitivity,
power cells, capacitors and serve to obtain antistatic
coatings and electrically conducting paint-and-varnish
materials. Prospects for their application in fabrication
of anticorrosion coatings and membrane systems and use
in nanotechnologies have been demonstrated.
However, the wide use of PANI-based composite
materials is hindered by a number of problem. Formation
of PANI coatings involves difﬁ culties due to the poor
solubility of the polymer in widely occurring polymers
and to its high glass-transition point exceeding the
destruction temperature. In this context, the most
applicable way to obtain the coatings is their formation
from aqueous dispersions. The oxidative polymerization
of aniline without a stabilizer yields a dispersion that
is fully sedimented during the ﬁ rst hour after stopping
the stirrer. However, it is known that the stabilization of
PANI dispersions is a complicated task . There have
been various studies concerned with the stabilization of
aqueous polyaniline dispersions, with anion-active or
nonionogenic surfactants used in all cases [2–11]. One
of ways to obtain stable aqueous dispersions of PANI is
by using polymeric surfactants having both anion-active
and nonionogenic groups in their composition.
Aqueous dispersions of polyaniline were produced
from aniline of chemically pure grade, additionally vac-
uum-distilled immediately before syntheses. Ammonium
persulfate of chemically pure grade was once recrystal-
lized from cold water before being used. As stabilizers
served polyvinyl alcohol (PVA) with 10–11.6 wt %
residual content of acetate units and M
≈ 130 000 and
polymeric carboxyl-containing surfactant with polyeth-
ylene glycol (PEG) fragments of varied length in the side
chain (Scheme 1).
The polymeric surfactants produced with PEG had
molar weights of 600 (PEG 600) and 1500 g mol
1500). Also, 1 : 1 and 2 : 1 mixtures of polyethylene
glycols with molar weights of 600 and 1500 were used
[PEG 600 : 1500 (1 : 1), PEG 60 : 1500 (2 : 1)].
Sulfuric and hydrochloric acids served as doping
agents without additional puriﬁ cation.