Russian Journal of Applied Chemistry, 2011, Vol. 84, No. 2, pp. 334−337.
Pleiades Publishing, Ltd., 2011.
Original Russian Text © N.V. Sirotinkin, M.G. Davudov, V.V. Bestuzheva, J.V. Omel’chuk, A.V. Tokarev, 2011, published in Zhurnal Prikladnoi Khimii, 2011,
Vol. 84, No. 2, pp. 338−341.
Glass Microballoons: Filling Agents
for Polyurethane Elastomers
N. V. Sirotinkin, M. G. Davudov, V. V. Bestuzheva, J. V. Omel’chuk, and A. V. Tokarev
St. Petersburg State Technological Institute, St. Petersburg, Russia
Received May 25, 2010
Abstract—Combustibility of polyurethanes in the presence of inert ﬁ lling agents: glass microballoons of a sodium-
borosilicate nature, was studied. The expediency of their use in the composition of elastomers for reduction of ﬁ re
danger was considered, and the effect of glass materials on their mechanical characteristics was studied.
In many branches of industry there is a necessity to
develop new materials or to modify existing materials
with the purpose to increase their operational tempera-
ture limit, ﬂ ame-resistance, mechanical strength, and
light stability simultaneously with reduction of the
thermal-conductivity coefﬁ cient, toxicity, and moisture
absorption [1, 2]. Filling up polymers by silicate materi-
als (glass-ﬁ ber, sand, alum earth, powdery asbestos, and
ﬁ nely divided silicon) is a known technique of raising
the ﬂ ame-resistance. It has been found that ﬁ lling agents,
in particular, glass microballoons (GMB) and hollow
glass microspheres (HGM) are useful in solution of the
enumerated problems [3, 4].
Modern technologies allow producing granular glass
powders, which represent a mechanical mixture of size-
graded monolithic or hollow spherical units of 50–250 μm
in diameter and greater. A smooth spheroid surface of
each of particles provides trauma-safety of the material,
safety of its storage and usage, and lends demanded
fabricability to processes with their involvement. Glass
powders are combined with polyester, epoxy, and phenol-
formaldehyde binding agents to form materials with
improved operation properties: GMB and HGM reduce
shrinkage and viscosity of compositions as compared
with geometrically shapeless particles of other ﬁ lling
agents, reduce an abrasive action, increase antifriction and
thermo-insulating indexes, impact strength, rigidity, and
also ﬂ ame-resistance of products. The above-enumerated
compositions are applied in house-building, automobile
industry, shipbuilding, aircraft, and space industries, and
in heat and power plants [3 –5].
Glass waste converting to products suitable for a reuse
makes it possible to solve simultaneously such problems
as removal of ecologically harmful long-time contamina-
tions from environment, minimization of raw, energy, and
labor expenditures, and production of various-function
new components for polymer-containing compounds.
To diversify glass-containing polymeric compositions,
glass microballoons of a sodium-borosilicate nature of
size up to 100 μm were used. Glass spheres were pre-
liminary dried at 120°С within 4 h. Oligoethers and oli-
goesters of SKU-PFL-100, SKU-PFL-74, SKU-PFL-65,
and SKU-7L grades served as polymeric supports. Their
properties are described in Table 1.
The oligomers were hardened by 3,3'-dichloro-4,4'-
diamono-diphenylmetahane (Diamet X) to form a seg-
mented polymeric structure. Glass microballoons of the
sodium-borosilicate nature were added at constant mixing
in the stage of the oligomer vacuum degassing.
In addition, a polyurethane product of secondary
treatment of industest wastage of ﬁ ne-meshed polyeth-
ylenebutyleneglycoladipinateurethane was used as a
binding agent for charged compositions. Its properties are
presented in Table 2 [6, 7]. A ﬁ lling agent was added to