Russian Journal of Applied Chemistry, 2013, Vol. 86, No. 4, pp. 564−567.
Pleiades Publishing, Ltd., 2013.
Original Russian Text © O.V. Alekseeva, N.A. Bagrovskaya, A.V. Noskov, A.S. Kraev, A.V. Agafonov, 2013, published in Zhurnal Prikladnoi Khimii, 2013,
Vol. 86, No. 4, pp.604−608.
AND POLYMERIC MATERIALS
Dielectric Parameters of Polystyrene Films
Modiﬁ ed with Fullerenes
O. V. Alekseeva, N. A. Bagrovskaya, A. V. Noskov, A. S. Kraev, and A. V. Agafonov
Krestov Institute of Solution Chemistry, Russian Academy of Sciences, Ivanovo, Russia
Received October 23, 2012
Abstract—The frequency dependences of the electrophysical parameters (capacitance, dielectric constant, dielectric
loss tangent, and resistivity) of polystyrene ﬁ lms doped with small (up to 1 wt % C
) additions of fullerenes were
determined by dielectrometry. The composite materials obtained were concluded to be nonpolar. The dielectric
constant as a function of the ﬁ lm composition passes through a minimum at 0.035 wt % С
. The polymer preserves
good insulating properties on doping with fullerenes.
The development of polymeric nanocomposites with
controllable structure and properties is one of priority
lines of the modern chemistry and materials science.
Harsh conditions of polymer operation in power engi-
neering and in chemical, petroleum, and pulp-and-paper
industries impose stringent requirements upon the proper-
ties of the polymers such as hardness, strength, and elec-
trophysical parameters. Doping of polymers with carbon
nanoparticles, fullerenes, improves the physicochemical
and operation characteristics of the materials .
One of the ﬁ rst polymers modiﬁ ed with fullerenes
was polystyrene (PS). Its macromolecules are capable
to bind С
. Because of the absence of polar groups,
the electrical conductivity of polystyrene is extremely
low (no more than 10
) , which allows its
wide use, e.g., in production of capacitors, of casings for
household devices, and of insulation for current leads.
It should be noted that doping with fullerenes inhib-
its thermal degradation of the polymer and imparts to it
antimicrobial properties. In particular, zones of inactiva-
tion of St. Aureus and E. Coli bacteria around samples of
polystyrene ﬁ lms modiﬁ ed with С
were revealed (Fig. 1)
. Therefore, fullerene-containing composite materials
show much promise in production of medical devices and
of items for household and sanitation purposes.
However, doping of polystyrene with fullerenes can
deteriorate its dielectric characteristics. In particular,
Adamopoulos et al.  studied the electrical properties
of thin polystyrene ﬁ lms doped with 23–60 wt % C
They found that an increase in the fullerene concentra-
tion leads to a monotonic increase in the high-frequency
dielectric constant of the material from 2.4 to 2.8 and
to a considerable (by 2 orders of magnitude) increase
in the electron mobility. Nourdine et al.  synthesized
fullerene-containing polystyrene-based polymers and re-
vealed a jumpwise increase in the electrical conductivity
(percolation threshold) at 4 vol % С
A still greater effect is attained on doping of PS with
another allotropic modiﬁ cation of carbon, graphene. A
jumpwise increase in the electrical conductivity occurs
on introducing into the polymer graphene in an amount
as low as 0.1 vol % .
Thus, when developing a composite material, it should
be taken into account that modiﬁ cation may improve
some properties of the polymer but simultaneously dete-
riorate other properties. Therefore, studies aimed to eluci-
date the composition–property relationship and to reveal
the optimal dopant concentration become very topical.
In this study we determined the dielectric parameters