ISSN 1070-4272, Russian Journal of Applied Chemistry, 2014, Vol. 87, No. 2, pp. 160−166. © Pleiades Publishing, Ltd., 2014.
Original Russian Text © N.K. Kitaeva, E.A. Bannova, 2014, published in Zhurnal Prikladnoi Khimii, 2014, Vol. 87, No. 2, pp. 177−184.
INORGANIC SYNTHESIS AND INDUSTRIAL
Modiﬁ cation of Track Membranes with Grafted
N. K. Kitaeva and E. A. Bannova
Obninsk Center for Science and Technology, Preobrazheniya pl. 1, Obninsk, Kaluga oblast, 249037 Russia
Received January 24, 2014
Abstract—Track membranes modiﬁ ed by the irradiation-chemical method with polymethacrylic acid were studied.
Grafted chains of polymethacrylic acid were impregnated with silver ions. The optimal parameters and conditions
of the post-irradiation grafting of methacrylic acid were determined. The effect of the grafted methacrylic acid
on porosimetric and hydrodynamic characteristics of a modiﬁ ed track membrane was studied. Impregnation with
silver ions makes it possible to obtain membranes with antimicrobial properties.
In recent years, membranes and membrane-based units
have been increasingly successfully used not only in the
already conventional areas, but also in novel ﬁ elds, which
requires that the so-called “special-purpose membranes”
should be developed. The most promising is use of spe-
cial-purpose track membranes (TMs) as microﬁ ltration
porous membranes because of the distinctive features of
TMs: narrow pore size distribution, nearly cylindrical
shape of pores, low adsorption capacity, and sieve ﬁ ltra-
tion mechanism . However, practical problems require
that certain surface properties of TMs should be changed,
which is provided by modiﬁ cation.
The high degree of crystallinity of polyethylene
terephthalate (PET), its insigniﬁ cant swelling in most of
organic solvents, low diffusion rate of initiators, and other
speciﬁ c features cause severe difﬁ culties in its chemical
modiﬁ cation. Therefore, the most promising modiﬁ ca-
tion method is by irradiation-chemical grafting of vinyl
monomers . This choice is based on the compara-
tively high radiation hardness of PET and preservation
or only a slight change of its important service, including
strength, characteristics upon irradiation. The membranes
produced by this kind of modiﬁ cation not only acquire
the functional properties of grafted polymers, but also
can be subjected to further modiﬁ cation via polymer-
analogous transformations or formation of interpolymer
complexes [3, 4].
The goal of our study was to examine the graft
polymerization of methacrylic acid (MAA) on a TM
preliminarily gamma-irradiated in air and to analyze the
antimicrobial properties of the modiﬁ ed TMs.
We used TMs based on a 12-μm-thick PET ﬁ lm,
produced by the reactor method . The pore diameters
were measured by the “bubble-point” method . The
pore size in the TMs was 0.4 μm, except in experiments
concerned with the dependence on the pore size.
To create grafting initiation centers, TMs were irra-
diated at room temperature in air in a
installation at a radiation dose rate of 0.05 Gy s
an absorbed ﬂ uence of 0.2 MGy.
MAA was grafted onto a radiation-oxidized surface of
TMs in a glass reactor in argon from aqueous solution of
the monomer in the presence of iron(II) methacrylate at
a temperature of 70°C. After the grafting was complete,
modiﬁ ed TM was washed in distilled water and dried
at room temperature to constant mass. Methacrylic acid
was not preliminarily washed to remove the stabilizer.