Russian Journal of Applied Chemistry, 2013, Vol. 86, No. 2, pp. 282−284.
Pleiades Publishing, Ltd., 2013.
Original Russian Text © N.V. Sirotinkin, M.G. Davudov, V.V. Samonin, Yu.M. Volin, 2013, published in Zhurnal Prikladnoi Khimii, 2013, Vol. 86, No. 2,
Effect of Silica-Alumina Microspheres on the Formation
of Open Porosity in Polymeric Materials
N. V. Sirotinkin, M. G. Davudov, V. V. Samonin, and Yu. M. Volin
St. Petersburg State Technological Institute, St. Petersburg, Russia
e-mail: ofﬁ email@example.com
Received October 23, 2012
Abstract—Effect of silica-alumina microspheres on the formation of open porosity in polymeric materials was
studied. Presence of porosity was conﬁ rmed by the moisture absorption and mercury porosimetry methods, and
causes of its origination and pore size distribution were determined.
Elastic materials, latex sponge rubber, polyurethane
foam, polyvinylchloride sponge, etc., receive ever-
growing acceptance in last years. Increase in production
of these materials is caused by rapid development of
transport, progress in designing, and also by a possibil-
ity of using these materials in various technical ﬁ elds as
sound- and heat-insulating material. Application of elastic
sponges facilitates a construction, simpliﬁ es mounting,
and provides perfect exterior appearance and longevity
of products . Various methods of foaming polymers
with the purpose of obtaining open- and close-porous
materials are known [2, 3], but insufﬁ cient attention is
given to the spontaneous origination of pores in ﬁ lled
Composite materials based on chloroprene Nairit L
latex and hollow spherical ﬁ ller, silica–alumina micro-
spheres (SAM) of LLC “MikroKompozit” production
were used as subjects of inquiry. The latex was chosen
due to a possibility of creating not easily combustible
The presence of open porosity in a material was esti-
mated by two methods: moisture absorption determina-
tion and mercury porosimetry.
Moisture absorption was determined according to
GOST 20869-75 . The method consists in the deter-
mination of water mass absorbed by an a material sample
dipped into water. Moisture absorption W
(%) was cal-
culated by formula (1).
= –——— × 100, (1)
is a sample weight before dipping into water
(g) and m
, a sample weight after a test (g).
The error in the determination of the moisture-
absorption was 0.2%.
Porosimetry tests were carried out on a mercury-
porosimetry installation. The method consists in pressing
mercury into samples of a porous material using pressures
from 0.027 up to 250 MPa, which makes it possible to
determine the presence of pores with radii from 3 up to
30 000 nm in a material .
The effect of SAM on the moisture absorption of a
material based on the Nairit L latex is shown in Fig. 1.
Increase in the SAM concentration results in an ap-
preciable increase in the moisture absorption of materi-
als based on the Nairit L latex. Owing to the difference
in coefﬁ cients of thermal expansion of the materials,
chloroprene latex and glass, hollows (open pores) appear
between the polymer matrix and microspheres in the
course of hardening. As the SAM concentration increases,
the amount of open pores increases, which results in the
increase in the moisture absorption by the material.
This method gives only approximate data on the po-
rosity of compositions.
To make a more complete estimate of the porosity