ISSN 1070-4272, Russian Journal of Applied Chemistry, 2008, Vol. 81, No. 4, pp. 717!719. + Pleiades Publishing, Ltd., 2008.
Original Russian Text + L.P. Varlamova, V.A. Izvozchikova, A.S. Averchenko, Yu.D. Semchikov, S.A. Ryabov, 2008, published in Zhurnal Prikladnoi
Khimii, 2008, Vol. 81, No. 4, pp. 681! 683.
Fireproof Polymer Compounds Based on Polyvinyl Chloride
and Perchlorovinyl Resin
L. P. Varlamova, V. A. Izvozchikova, A. S. Averchenko, Yu. D. Semchikov, and S. A. Ryabov
Research Institute of Chemistry, Lobachevsky State University, Nizhni Novgorod, Russia
Lobachevsky State University, Nizhni Novgorod, Russia
Received July 5, 2007
Abstract-Preparation of fireproof polymer compounds and properties of the resulting materials were
studied. The synergistic effect of mixtures of fire-retardant additives based on thermally expanding graphite
Most procedures for diminishing the combustibility
of polymer materials are based on decreasing the burn-
ing limits and affecting the heat and mass transfer
of the flame with the surface of the burning polymer.
This problem is solved by changing the thermal and
thermochemical characteristics of the condensed phase
and by lowering the rate of release of combustible
gases (products of polymer degradation), the combus-
tion efficiency, and the rates of oxidation in the gas
phase and coke formation. This can be done by chem-
ical modification of the polymer backbone and by
addition of fire-retardant additives or other fillers that
are characterized by high endothermic effect and re-
lease inert reaction products or affect the degradation
pathway in the condensed phase [1, 2].
Swelling fireproof coatings are of particular interest
for construction industry, machine building, transport,
etc. . A formulation for swelling coatings containing
ammonium polyphosphate as an agent for initiation
of the foamed coke formation was suggested in .
In this study, we examined the effect of fillers,
such as thermally expanding graphite (TEG), am-
monium polyphosphate (APP), and pentaerythritol
(PE), on the fireproof properties of polymer materials.
Thermally expanding graphite  bloating at ele-
vated temperatures was used as the main component
of the system. In combustion, the volume of TEG con-
siderably increases, which is accompanied by heat ab-
sorption and formation of a heat-shielding carbon foam
preventing fire propagation. However, the strength of
the resulting carbon foam layer is low, and it is easily
broken under the conditions of real fire.
The mechanical strength of the protective carbon
foam can be enhanced by modification with various
The refractoriness of the polymer materials was
studied by the UL-94 international procedure [GOST
(State Standard) 28 1573 89], according to which a ma-
terial of group V-0 is characterized by the highest re-
The oxygen index (i.e., the minimal content of
oxygen in the oxygen3nitrogen mixture at which
the candle-like combustion is possible under the con-
ditions of special tests) was determined in accordance
with GOST 12.1.044389 . The physical and mech-
anical properties of the polymer materials were stud-
ied on an RMI-5 tensile-testing machine, and the elas-
ticity, on an METEFEM-khr01 unit.
When exposed to high temperatures in the course
of combustion, a polymer composite containing TEG
is bloated, and a crust is formed on its surface.
It was found that the resulting coke layer (foam)
prevents further fire propagation toward the protected
surface. The intumescence coefficient K
of the poly-
mer material was determined as follows: