PREPARATION OF HEAT INSULATION MATERIAL FROM WATER GLASS
MODIFIED WITH SODIUM CHLORIDE
D. Yu. Denisov,
V. A. Kulikov,
V. Z. Abdrakhimov,
I. V. Kovkov,
E. V. Vdovina,
V. A. Mikheev,
L. V. Zhuravel’,
and I. Yu. Roshchupkina
Translated from Novye Ogneupory, No. 9, pp. 27 – 30, September 2011.
Original article submitted July 26, 2011.
Studies show that it is possible to prepare heat insulation material from water glass, modified with sodium
chloride, at a relatively low temperature of 350°C. The main condition providing swelling of water glass sys
tems on heating is a combination in time of a pyroplastic condition with intense steam separation within heat
Keywords: water glass, heat insulation material, modifier, sodium chloride, physicomechanical properties,
silicate modulus, rheological parameters.
Currently it is very challenging to find even one branch
of technology and industry where soluble glass has not been
used. In the building material industry water glass is used for
securing soils, preparation of acid-resistant concretes and ce-
ments, facing and acid-resistant plates, etc. As is well
known, the main operating properties of heat insulation ma-
terials are thermal conductivity, density, and strength. Heat
insulation materials based on soluble sodium glasses corre-
spond to these specifications [1 – 3].
Research, whose results are given in this article, is aimed
at preparing heat insulation material from water glass, modi
fied with sodium chloride with heat treatment above 350°C.
Water glass is a colloidal aqueous solution of sodium or po
tassium silicate, having a density of 1.3 – 1.5 g/cm
water content of 50 – 70% . The composition of alkali sili
cates is expressed by the equation R
, where R is Na
or K; m is water glass modulus (the modulus of sodium is
2.6 – 3.5, and fro potassium it is 3 – 4). This equation means
that for one molecule of alkali oxide there are m silica mole
The aim of this work is preparation of heat insulation
material from a water glass composite. The following com
ponents were used in order to prepare heat insulation mate
rial: commercial sodium water glass with a density of
(GOST 13075), sodium chloride (GOST 13830,
produced OAO Basol’), ground to a particle size of less than
0.3 mm. Previously [2,3–8]ithas been demonstrated that
in order to prepare heat insulation material it is desirable to
use commercial water glass, whose physicomechanical prop-
erties are provided below:
sodium oxide ..........................10.63
Siliceous modulus ..........................3.0
Silicate modulus ...........................2.9
Rheological parameters are required in the production of
heat insulation materials based on water glass with structure
formation, and as a rule three problems are created: in the
state of mixing (giving the raw material mix homogeneity);
in the formation stage a capacity to maintain a prescribed
form; in the finished heat insulation material preparation
stage, within which it is desirable to obtain a uniform
fine-grained structure. Being a sodium hydrated silicate and
having high absorption capacity, water glass makes the mix
ing process very difficult.
The nature of deformation processes in dispersed sys
tems is determined by their rheological properties. Rheology
is the science of substance deformation and flow, and as a
rule three types of system are considered that may be differ
ent with respect to their rheological properties: Newtonian
(true) liquids, liquid structure formation, not exhibiting a
limiting shear stress, and plastically-viscous systems exhibit
ing a limiting shear stress [9, 10]. In turn, rheological param
eters are governed by molecular adhesion forces between
Refractories and Industrial Ceramics Vol. 52, No. 5, January, 2012
1083-4877/12/05205-0331 © 2012 Springer Science+Business Media, Inc.
Samara Academy of State and Municipal Management, Samara,
Samara State Aerospace University, Samara, Russia.
Samara State University, Samara, Russia.