ISSN 1070-4272, Russian Journal of Applied Chemistry, 2014, Vol. 87, No. 3, pp. 303−306. © Pleiades Publishing, Ltd., 2014.
Original Russian Text © M.A. Paserb, I.N. Bakirova, V.I. Valuev, 2014, published in Zhurnal Prikladnoi Khimii, 2014, Vol. 87, No. 3, pp. 337−341.
AND POLYMERIC MATERIALS
Polyurethane (PU) materials possessing valuable
physical and mechanical properties are characterized
by signiﬁ cant drawback: low resistance to open ﬂ ames
and high temperatures. One method of improving the
thermal characteristics of PU consists in modiﬁ cations
with oligoesters, which are the primary components
of their synthesis. Previously published reports have
shown that the introduction of aromatic moieties of oli-
goester in a chain enhances thermal and ﬁ re resistance
of PU [1, 2]. Phthalic acid or anhydrides thereof as a
rule are used in order to introduce the phenyl rings in
the oligoester structure . However, this goal can be
achieved also by replacing the aliphatic diol for aromat-
ic. In the study we propose to use hydroxyethylated di-
phenylolpropane derivatives as monomers. Information
about applying the diols is scarce and is of mostly patent
character: there are reports of their use as components
for synthesis of saturated and unsaturated polyesters in
combination with terephthalic acid, isophthalic acid,
and ethylene glycol [4–6].
The aim of the study is the synthesis of new aromatic
oligoesters with terminal hydroxyl groups on the basis
of hydroxyethylated derivatives of diphenylolpropane
and dicarboxylic acids, examination of their molecu-
lar weight characteristics, testing varnish compositions
in the PU synthesis, examination of physicomechani-
cal properties and thermal stability of PU coatings and
Hydroxyethylated derivatives of diphenylolpropane
were used as starting substances: 2,2-bis[4-(2-hydroxy-
ethoxy)phenyl]propane (DPP-1), which was synthesized
according to the procedure described in patent ,
mp = 110°C, a hydroxyl number 353 mg KOH/g, and
(Aldrich), a hydroxyl number 220–235 mg KOH/g. Also
the following substances were used: adipic acid (AA)
(Aldrich), mp = 153°C; sebacic acid (SA) (Vekton), mp =
134.5°C; polyisocyanate (PIC) (Korund), isocyanate
group content 31 wt %, State Standard TU 113-03-38-
106-90; ethyl acetate, State Standard GOST 8981-78.
The scheme of synthesis of oligoesters is given below.
The process was conducted in the melt in two steps.
The ﬁ rst step was carried out at 150–180°C in argon
ﬂ ow, the second at 180–200°C and residual pressure of
10 mmHg. The resulting oligoesters were of hydroxyl
numbers 56.1–151.8 mg KOH/g, acid number of 0.4–
2.6 mg KOH/g.
Varnish PU compositions were prepared by dissolving
of oligoesters in ethyl acetate followed by addition
of PIC. For 20 min after stirring the composition was
applied to a substrate. An amount of components was
calculated based on a molar ratio of groups NCO : OH =
1 : 1, a fraction of dry residue was 40 wt %.
New Aromatic Oligoesters and Their Use
in the Synthesis of Heat-Resistant Polyurethane Coatings
M. A. Paserb
, I. N. Bakirova
, and V. I. Valuev
Kazan National Research Technological University, ul. Karla Marksa 68, Kazan, 420015 Russia
FSUE “NIISK,” ul. Gapsal’skaya 1, St. Petersburg, 198035 Russia
Received February 21, 2014
Abstract—For manufacturing new varnish polyurethane coatings with high hardness and elasticity at maintaining
adhesion and strength properties oligoester diols were synthesized based on hydroxyethylated diphenylpropane
derivatives and aromatic dicarboxylic acids.