Russian Journal of Applied Chemistry, 2011, Vol. 84, No. 9, pp. 1587−1590.
Pleiades Publishing, Ltd., 2011.
Original Russian Text © I.M. Davletbaeva, A.M. Gumerov, A.F. Galyautdinova, R.S. Davletbaev, O.K. Krasil’nikova, 2011, published in Zhurnal Prikladnoi
Khimii, 2011, Vol. 84, No. 9, pp. 1537−1541.
AND POLYMERIC MATERIALS
Polymers Derived from a Polyether,
2,4-Toluene Diisocyanate, and Octamethylcyclotetrasiloxane
I. M. Davletbaeva
, A. M. Gumerov
, A. F. Galyautdinova
R. S. Davletbaev
, and O. K. Krasil’nikova
Kazan State University of Technology, Kazan, Tatarstan, Russia
Tupolev Kazan State Technical University, Kazan, Tatarstan, Russia
Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow, Russia
Received December 30, 2010
Abstract—Polymers prepared from a polyether, 2,4-toluene diisocyanate, and octamethylcyclotetrasiloxane were
studied using thermomechanical analysis, mechanical tests, and water vapor adsorption. The adsorption of nitrogen
vapor was studied at 77 K, and that of water vapor, at 293 K.
Preparation of siloxane–urethane block copolymers
is an important goal of polymer science and engineering.
Such copolymers exhibit gas-separation properties and
are biocompatible. The known procedures for preparing
siloxane–urethane block copolymers are based on
copolycondensation of oligoorganosiloxanediols with
urethane prepolymers containing terminal isocyanate
groups [1, 2]. In this case, the hydroxy group should not
be directly bonded to the Si atom, because the reaction
of such silanol group with the isocyanate group results
in the formation of a hydrolytically unstable Si–O–C
bond as a constituent of the urethane fragment. For
the block copolymers to be hydrolytically stable, it is
necessary that the hydroxy group be bonded with the Si
atom via C atom. Such approach gives rise to additional
technological problems in the synthesis of siloxane–
urethane block copolymers by copolycondensation.
Another problem is that an increase in the content of
the dimethylsiloxane component in siloxane–urethane
block copolymers leads to an appreciable decrease in the
strength characteristics. A new direction in the synthesis
and study of organosiloxane polymers, allowing their
production process to be changed and opening new ﬁ elds
of application of polymeric materials, is polyaddition of
dimethylsiloxane rings to a macroinitiator and formation
of thickly cross-linked structures.
In this study we evaluated the mechanical characteristics
and sorption ability of polymers prepared from aromatic
isocyanates, octamethylcyclotetrasiloxane, and
In our study we used a block copolymer of
propylene oxide with ethylene oxide (polyether
4202-2B-30 of grade Shch) (PPEG-K) of the formula
where n = 15, m = 51, prepared according to TU
(Technical Speciﬁ cation) 6-01-646–84 (10% potassium
alcoholate groups relative to the total amount of
functional groups); 2,4-toluene diisocyanate (TDI);
), prepared according
to TU 38-10385–76; and chemically pure grade toluene.
2,4-Toluene diisocyanate was puriﬁ ed by vacuum
distillation at a residual pressure of 0.07 kPa.
Poly(urethane–siloxane) polymers were prepared
by the reaction of PPEG-K polyether, 2,4-toluene
diisocyanate, and octamethylcyclotetrasiloxane in