ISSN 1070-4272, Russian Journal of Applied Chemistry, 2015, Vol. 88, No. 8, pp. 1368−1374. © Pleiades Publishing, Ltd., 2015.
acid) Hydrogels, Prepared by Frontal Polymerization
in Aqueous Solutions
, E. V. Grinyuk, and L. P. Krul’
Belarussian State University, Leningradskaya str. 14, Minsk, 220030 Belarus
Received September 23, 2015
Abstract—Polyelectrolyte hydrogels based on copolymers of acrylamide with 2-acrylamido-2-methylpropane-
sulfonic acid were prepared by frontal copolymerization in dilute aqueous solutions of the monomers using am-
monium persulfate as initiator chromium triacetate as cross-linking agent. The inﬂ uence of the monomer molar
ratio, initiator and cross-linker concentration on the possibility of performing the copolymerization and monomer
reactivity ratios in the frontal mode, and on the characteristics of the obtained hydrogels was examined.
The text was submitted by the authors in English.
Up to now, characteristics and applications of poly-
meric hydrogels are frequently discussed in detail [1–3].
By deﬁ nition, a hydrogels is a cross-linked polymer
network with hydrophilic properties. In general, the three
integral parts of the hydrogels synthesis occur: monomer,
initiator, and cross-linker. The hydrogels properties can be
modulated by varying the parameters of synthesis, such
as type and amount of cross-linker, type and concentra-
tion of monomer, type and amount of initiator, reaction
vessel, reaction time, and reaction temperature .
Acrylamide and its N-substituted derivatives are widely
used for synthesis of water soluble polymers and hydro-
philic gels which ﬁ nd applications in cosmetics, paints,
waste-water treatment, biomedical applications, and oil
recovery [5, 6]. Introduction of anionic comonomers
to monomer mixture increases the swelling capacity of
such hydrogels. Anionic acrylamide copolymers such as
poly(acrylamide-co-sodium acrylate), poly(acrylamide-
(AA/NaAMPS), and poly(acrylamide co-2-acrylamido-
2-methyl-1-propanesulfonic acid) (AA/AMPS) are of
considerable importance in enhanced oil recovery (EOR)/
improved oil recovery (IOR) . Among anionic mono-
mers, AMPS is of more special interest due to strongly
ionizable sulfonate group and complete dissociation in the
whole pH range. Thus, the hydrogels derived from AMPS
exhibit pH independent swelling behavior . In EOR/
IOR applications, metallic ions such as Cr
be injected with anionic polyacrylamides to cross-link
the polymers in more permeable reservoir zones prior to
the water ﬂ ood. In general, all of the above-mentioned
hydrogels can be prepared in solution, inverse emulsion
, and inverse micro-emulsion . In order to control
the heat of polymerization and the ﬁ nal hydrogels proper-
ties, diluents can be used, such as water or other aqueous
solutions. In recent years, needs to facile preparation
of hydrogels and environmental requirements such as
minimization of residual monomer content in biomedical
applications, resulted in development of some old well-
known methods and techniques.
Frontal polymerization (FP) is one of these processes.
FP is the process of converting monomer into polymer in
a localized reaction zone. One of three major modes of FP