Russian Journal of Applied Chemistry, 2011, Vol. 84, No. 7, pp. 1266−1270.
Pleiades Publishing, Ltd., 2011.
Original Russian Text © S.A. Kotel’nikov, A.S. Ermilov, E.D. Chirkova, 2011, published in Zhurnal Prikladnoi Khimii, 2011, Vol. 84, No. 7, pp. 1196−1200.
AND POLYMERIC MATERIALS
Rheological Properties of Binders
Based on Oligoester Urethanes
S. A. Kotel’nikov, A. S. Ermilov, and E. D. Chirkova
Perm State Technical University, Perm, Russia
Received July 27, 2010
Abstract—Rheological characteristics of solutions of oligoester urethanes with terminal double bonds in a mixed
polar plasticizer were studied. Mathematical models describing the dependence of the solution viscosity and
activation energy of the viscous ﬂ ow on the plasticizer content, and also the dependence of the viscosity on the
temperature and concentration were discussed.
Urethane polymers are widely used in adhesive
formulations, in production of structural materials,
and as binders for ﬁ lled polymeric composites [1, 2].
It should be noted that, with high-molecular-weight
rubbers, the viscosity of the system increases, and hence
the stirring becomes more power-consuming. One of the
ways to solve this problem is the use of an oligomeric
binder (e.g., oligoester urethane) allowing the viscosity
of the compound to be decreased. With oligoester
urethanes, it is possible to control the physicomechanical
characteristics of vulcanizates. In addition, oligoester
urethanes derived from polyesters are compatible
with active polar plasticizers [3, 4]. Furthermore, the
use of the prepolymeric method for the synthesis of
urethane oligomers allows preparation of oligomeric
compounds with different functional groups, and the
use of new curing systems allows curing of items at low
temperatures, which also reduces the power consumption
for production of polymeric compounds. Of much
interest in this respect are oligoester urethanes with
terminal double bonds whose low-temperature curing
can be effected by nitrile oxides. There are indications
in the literature that nitrile oxides show promise as low-
temperature curing agents for unsaturated rubbers [5–7].
In this study we examined the rheological proper-
ties of new oligomeric binders curable at low tempera-
tures, unsaturated oligoester urethanes P-9D (double
bond content 3.6 wt %) derived from linear polyester
P-9, 2,4-toluene diisocyanate (TDI), and allyl alcohol
and P-9AD (double bound content 2.75 wt %) derived
from weakly branched polyester P-9A, TDI, and allyl
The synthesis was performed in two steps with the
formation in the ﬁ rst step of an intermediate isocyanate-
containing urethane prepolymer by the reaction of the
polyester with TDI at NCO : OH = 2 : 1. In the second
step, to obtain a product with terminal double bonds,
to this prepolymer we added allyl alcohol in an amount
corresponding to the equimolar ratio of the NCO groups
of the prepolymer and OH groups of the alcohol.
Rheological studies were performed with solutions
of oligoester urethanes in a mixed polar plasticizer
(mixture of di- and triethylene glycol dinitrates, weight
ratio 70 : 30) on a Hoeppler rheoviscometer at 30, 40,
and 50°С, following the standard procedure. Figures 1a
and 1b show the examples of the dependences of the
viscosity on the shear rate at the oligoester urethane to
plasticizer weight ratio of 50 : 50.
The shape of the other dependences of the viscosity