1070-4272/04/7703-0454C2004 MAIK [Nauka/Interperiodica]
Russian Journal of Applied Chemistry, Vol. 77, No. 3, 2004, pp. 454! 457. Translated from Zhurnal Prikladnoi Khimii, Vol. 77, No. 3,
2004, pp. 461! 464.
Original Russian Text Copyright + 2004 by Amirova, Magsumova.
AND POLYMERIC MATERIALS
Energy Characteristics of the Surface of Modified
Phosphorus-Containing Epoxy Polymers
L. M. Amirova and A. F. Magsumova
Tupolev Kazan State Technical University, Kazan, Tatarstan, Russia
Received April 22, 2003
Abstract-The Fowkes and van Oss3Good approaches were used for assessing the energy characteristics of
the surface of the epoxy3amine systems modified with triglycidyl phosphate. Variation of these characteristics
with the modifier content and polymer curing conditions was studied.
Modification of the initial oligomer systems allows
control of the surface properties of cured polymers.
It is known [1, 2] that the components of compounds
differ in the adsorbability, which can be responsible
for differences in their distribution in the bulk and at
interfaces [1, 2]. This allows formation of surfaces
with desired energy characteristics.
The surface energy g
of solids at the solid3liquid
or solid3gas interfaces is often assessed using the
Fowkes3Owens [3, 4] and van Oss3Good [5, 6] ap-
proaches. They are based on measuring the contact
angles of wetting of the surface with test liquids.
The surface energy and its components were estimated
for a number of epoxy polymers [1, 2, 7, 8]. Rudoi
and co-workers  and Chalykh and co-workers 
showed that the surface activity of modified epoxy
systems is governed by a number of factors such as
ratio of the rates of the chemical reaction and diffu-
sion, molecular weight, and the curing mode chosen.
However, the above-cited works, even though con-
cerned with the same epoxy systems, report different
surface energies. Van Oss and co-workers [5, 6] as-
sessed the acid3base properties of the surface of epoxy
polymers and revealed their basic nature.
We found earlier  that modification of
epoxy34,4`-isopropylidenediphenol oligomers with
glycidyl esters of phosphorus-containing acids (GEPs)
yields materials with enhanced thermophysical, phys-
icomechanical, and optical properties. At the same
time, when the developed phosphorus-containing
epoxy compounds are intended as adhesives, prepara-
tion of coatings requires knowledge of the surface and
interphase properties of both uncured oligomer sys-
tems and polymers thereof.
The aim of this work is to quantitatively estimate
the energy characteristics of the surface of polymers
based on ED-20 epoxy-4,4`-isopropylidenediphenol
oligomer modified with triglycidyl phosphate.
We used ED-20 epoxy34,4`-isopropylidenediphenol
oligomer I, triglycidyl phosphate P(O)(OCH
II, and 4,4`-diaminodiphenylmethane
Oligomer I was vacuum-treated at 80390oC, where-
upon the contents of epoxy and hydroxy groups were
estimated by chemical methods  (at 21.5 and
1.3%, respectively). Triglycidyl phosphate II was
synthesized as described by Rizpolozhenskii et al.
, purified by vacuum distillation, and kept in
sealed glass ampules. The compound was identified
by elemental analysis and IR and
The compatibility of I and II was checked by
microinterferometry on an MI-2 instrument. Based on
the data obtained, we constructed phase diagrams.
Mixtures of I and II of different compositions were
cured with a stoichiometric amount of DADPM in
a stepwise mode (heating to 60oC and curing for 6 h
at 20oC) and postcured in a stepwise mode as well
(heating for 1 h at 1003170oC with a 10oC step).
The surface energy of the resulting polymers and
its components were estimated from the angle of wet-
ting with test liquids. The contact wetting angles were
determined using a horizontal microscope equipped
with a goniometric accessory, under saturated liquid