ISSN 1070-4272, Russian Journal of Applied Chemistry, 2014, Vol. 87, No. 12, pp. 1872−1876. © Pleiades Publishing, Ltd., 2014.
Original Russian Text © S.V. Samchenko, O.V. Zemskova, I.V. Kozlova, 2014, published in Zhurnal Prikladnoi Khimii, 2014, Vol. 87, No. 12, pp. 1795−1800.
PROCESSES AND EQUIPMENT
OF CHEMICAL INDUSTRY
Stabilization of Carbon Nanotubes with Superplasticizers
Based on Polycarboxylate Resin Ethers
S. V. Samchenko, O. V. Zemskova, and I. V. Kozlova
Moscow State Building University, Yaroslavskoe sh. 26, Moscow, 129337 Russia
e-mail: firstname.lastname@example.org; email@example.com
Received August 29, 2014
Abstract—The mechanism of stabilization of carbon nanotubes by ultrasonic treatment in the presence of a
superplasticizer of new generation, based on polycarboxylate resin ethers, is analyzed. The main factors deter-
mining the stability of lyophobic systems as applied to solutions of stabilized carbon nanotubes are considered.
The plots illustrating the efﬁ ciency of using solutions of stabilized carbon nanotubes in production of cement
composites are presented. The solutions of stabilized carbon nanotubes preserve their properties for a long time.
This feature allows preparation of repair mixes with required properties for performing various building works.
The development of effective materials exhibiting
essentially new properties is largely based on the
development of nanotechnologies. Particular attention
is given to this research ﬁ eld in Russia, and it ensured
accelerated scientiﬁ c and technical progress in various
Nanotechnologies are promising and efﬁ cient for the
development of building materials also [1–4]. Among
diverse nanomaterials used as additives in the production
of cement, concrete, dry building mixes, and other binding
materials, carbon nanotubes (CNTs) are of most interest
for building industry. Carbon nanotubes were discovered
almost 20 years ago as by-products of fullerene (C
synthesis. They combine the properties of molecules
and solids and can be considered as an intermediate state
of a substance, which is reﬂ ected in high levels of such
CNT characteristics as electrical conductivity, elastic
modulus, and mechanical strength. The set of these
properties allows using CNTs as dispersed reinforcing
component for high-strength composite materials.
However, the use of CNTs in production of building
materials is restricted by their increased tendency to
agglomeration, leading to nonuniform distribution of
nanoparticles in the bulk of a composite material and to
insufﬁ cient adhesion to the binding matrix, which causes
instability of physicomechanical properties and often their
deterioration. The dispersion and stabilization of CNTs
can be ensured in an aqueous system.
The best known dispersing and stabilizing agents for
cement dispersions are various kinds of superplasticizers.
The majority of them are produced on the basis of
sulfonated melamine– and naphthalene–formaldehyde
resins (Melment, S-3, etc.). They form on the liquid/
solid interface a ﬁ lm that acts as a structural-mechanical
barrier consisting of linear molecules, which causes
immobilization of adsorption-bound water and prevents
its access to the surface of clinker materials. As a result,
the hydration in early steps of setting of a cement–water
system is decelerated [5, 6].
Today, the most widely used superplasticizers are
those on polycarboxylate base (Мelﬂ ux, Sika Visckocrete,
etc.), exerting combined electrostatic and steric effect
The backbone is responsible for the electrostatic
repulsion, and pendant groups, for steric repulsion.
Increased length of pendant chains and decreased length
of the backbone led to a decrease in the density of the
surfactant adsorption on the surface of a cement grain,
which left a part of active sites uncovered by a polymer