1070-4272/05/7812-1993 C 2005 Pleiades Publishing, Inc.
Russian Journal of Applied Chemistry, Vol. 78, No. 12, 2005, pp. 1993!2001. Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 12, 2005,
Original Russian Text Copyright + 2005 by Smirnov, Kuryndin, Nikitin, Sidorovich, Sazanov, Kudasheva, Bukošek, Khokhlov, Elyashevich.
AND POLYMERIC MATERIALS
Properties of Conducting Composite Systems Containing
Polypyrrole Layers on Porous Polyethylene Films
M. A. Smirnov, I. S. Kuryndin, L. N. Nikitin, A. V. Sidorovich, Yu. N. Sazanov,
O. V. Kudasheva, V. Bukošek, A. R. Khokhlov, and G. K. Elyashevich
Institute of Macromolecular Compounds, Russian Academy of Sciences, St. Petersburg, Russia
Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Moscow, Russia
Ljubljana University, Ljubljana, Slovenia
Received November 1, 2005
Abstract-Conducting composite systems containing polypyrrole layers were prepared by in situ polymeriza-
tion of pyrrole on the surface of porous polyethylene films. The polymerization was performed in the gas
phase, in a monomer solution, and in supercritical CO
. The chemical structures, electrical conductivities, and
mechanical, thermodeformational, and morphological characteristics of the composites obtained were compared.
Conducting polymers, such as polypyrrole (PPyr),
polyaniline, polythiophene, and their derivatives, have
been extensively studied recently because of the wide
prospects for their application. Thanks to a combina-
tion of electrical, magnetic, optical, and electrochem-
ical properties, these polymers are widely used as
membranes, electrochemical sensors, electrode mate-
rials, etc. [1, 2]. Among conducting polymers, poly-
pyrrole attracts particular attention owing to its rela-
tively high chemical stability . However, this poly-
mer has a low mechanical strength and is very brittle,
which substantially restricts its potential applications.
One of the best ways to solve this problem is to pre-
pare composite systems in which an elastic support
would provide the required mechanical properties
and the conducting polymer would be the active com-
We have shown previously  that porous poly-
ethylene (PE) films can be efficiently used as supports
for PPyr layers. These films exhibit high adhesion
to various coatings, including layers of conducting
polymers. We found that the high adhesion is due
to the developed profile of the film surface and to
the presence of a large amount of through flow chan-
nels, providing a tight fixation of the coating.
Numerous procedures for preparing PPyr are known
. As the structure and, hence, the properties of
a conducting polymer largely depend on the procedure
and conditions of its preparation [8, 9], it is of partic-
ular interest to compare the characteristics of conduct-
ing composite systems with the active component
prepared by different procedures.
In this paper, we compare the electrical, mechani-
cal, thermodeformational, and morphological proper-
ties of PE/PPyr composite systems prepared by both
well-known and new procedures, one of which is the
polymerization in supercritical CO
. The last pro-
cedure is also attractive from the environmental view-
point, as involving no toxic solvents and initiators.
The porous films were prepared from HDPE with
= 1.4 0 10
=638, and T
The porous structure was formed by uniaxial exten-
sion of films prepared by the melt extrusion followed
by annealing [10, 11]. The film thickness was 12 mm,
and the overall porosity, 48%. The porous films con-
tained through flow channels of size 1803500 nm .
An important feature of these films is the strongly
developed surface profile (Fig. 1) produced by uni-
axial extension of annealed films at the stage of pore
formation. The profile scale increases with the degree
of orientation of the support, ranging in the interval
examined from 0.2 to 0.8 mm.
To prepare PPyr by polymerization of the mono-
mer in solution and in the gas phase, we used pyrrole
(Vekton) as oxidant, and methanol
(Vekton). For the synthesis in supercritical CO
used 99.998% pure CO
[BKZ Linde Gas AGA, Bala-
shikha; GOST (State Standard) 8050385] and pyr-
role-2-carboxylic acid (Aldrich).