Russian Journal of Applied Chemistry, 2012, Vol. 85, No. 11, pp. 1780−1785.
Pleiades Publishing, Ltd., 2012.
Original Russian Text © A.I. Hloba, V.I. Grachek, E.T. Krut’ko, 2012, published in Zhurnal Prikladnoi Khimii, 2012, Vol. 85, No. 11, pp. 1876−1883.
AND POLYMERIC MATERIALS
Imide-Containing Oligomers as Alkyd Resin Modiﬁ ers
A. I. Hloba
, V. I. Grachek
, and E. T. Krut’ko
Belarusian State Technological University, Minsk, Belarus
Institute of Physical Organic Chemistry, National Academy of Sciences of Belarus, Minsk, Belarus
Received May 29, 2012
Abstract—Organo-soluble imide-containing oligomers (oligomaleimidohydroxyphenylene and oligoimide derived
from benzalazine and m-phenylenebismaleimide) were examined as modiﬁ ers for melamine–alkyd and alkyd resins.
Addition of these modiﬁ ers enhances the hardness, impact strength, and corrosion resistance of the coatings and
their adhesion to metal surfaces, i.e., improves the service properties of the coatings.
Alkyd resins are widely used as components of paint-
and-varnish materials suitable for making protective
coatings for various purposes. However, they have some
drawbacks: high brittleness, low hardness, and insuf-
ﬁ cient water resistance.
One of the ways to improve properties of materials
is the use of new monomers of various chemical struc-
tures in their synthesis . However, a more efﬁ cient
and easier-to-implement way to meet the requirements
of speciﬁ c applications of paint-and-varnish coatings is
chemical modiﬁ cation of commercially available poly-
meric ﬁ lm-forming substances .
The goal of this study is the development of
imide-containing ﬁ lm-forming formulations based on
melamine–alkyd and alkyd resins for making protective
coatings with improved service properties.
As investigation objects we used commercially
produced melamine–alkyd lacquer of grade ML-0136
[Lakokraska Public Joint-Stock Company, Lida, Belarus,
TU (Technical Specification) 6-10-1392–78] and
alkyd resin synthesized using 5,6-benzbicyclo[2.2.2]
octan-8-one-2,3-dicarboxylic anhydride (BBA) as acid
BBA was prepared in one step by Diels–Alder conden-
sation of β-naphthol with maleic anhydride in a melt at
220°С for 2 h in a nitrogen stream .
The alkyd resin was prepared by the two-step scheme.
In the ﬁ rst step, we performed ester interchange of reﬁ ned
ﬂ axseed oil with polyfunctional alcohols: glycerol and
pentaerythritol. The second step was polycondensation
of BBA with the mixture of glycerides formed in the
ﬁ rst step .
As modifying components we used oligomeric imide-
containing compounds: oligomaleimidohydroxyphenylene
(OMIHP) and an oligoimide derived from benzalazine
and m-phenylenebismaleimide (OI).
The choice of these oligomers as modiﬁ ers was gov-
erned by their chemical structure: presence of reactive
terminal and pendant maleimide groups and three-dimen-
sional structure of the macromolecules. The oligomers
are readily soluble in polar aprotic solvents and exhibit
high heat resistance owing to the presence of imide rings.
The Hildebrand solubility parameters calculated for the
alkyd resin, melamine–formaldehyde resin, and imide-
containing oligomers are close (Table 1), suggesting ther-
modynamic compatibility of melamine–formaldehyde
and alkyd resins with imide-containing oligomers .
It was confirmed experimentally that alkyd and
melamine–alkyd resins are well miscible with solutions
of imide-containing oligomers: The formulations undergo
no phase segregation on storage for at least 1 month,