Russian Journal of Applied Chemistry, 2009, Vol. 82, No. 8, pp. 1483−1487.
Pleiades Publishing, Ltd., 2009.
Original Russian Text
M.Sh. Gurbanov, B.A. Mamedov, 2009, published in Zhurnal Prikladnoi Khimii, 2009, Vol. 82, No. 8, pp. 1384−1388.
AND POLYMERIC MATERIALS
Epoxidation of Flax Oil with Hydrogen Peroxide
in a Conjugate System in the Presence of Acetic Acid
and Chlorinated Cation Exchanger KU-2×8 as Catalyst
M. Sh. Gurbanov and B. A. Mamedov
Institute of Polymeric Materials, National Academy of Sciences of Azerbaijan, Sumgait, Azerbaijan
Received July 8, 2008
Abstract—Epoxidation of flax oil in a conjugate system with hydrogen peroxide using chlorinated cation exchanger
KU-2×8 as catalyst was studied. The influence exerted on the epoxidation rate and target product quality by the
temperature, stirring intensity, catalyst amount, and reactant ratio was examined.
Epoxidized vegetable oils are widely used in polymer
chemistry. These products are not only excellent
plasticizers of poly(vinyl chloride), but also its efﬁ cient
stabilizers . Therefore, they are widely used as
components of stabilizing formulations.
From the process viewpoint, it is convenient and
advantageous to perform epoxidation of vegetable oils
in one step, i.e., with peroxy acids formed in situ from
carboxylic acids and hydrogen peroxide in the presence
of acid catalysts [2–5]. However, conjugate oxidation
of vegetable oils in the presence of mineral acids is
inefﬁ cient because of problems with separation of the
catalyst from the reaction products. On the other hand,
preparation and isolation of peroxy acids in advance
involves explosion hazard.
The most advantageous is the use of ion-exchange
catalysts both in synthesis of peroxy acids [6, 7] and
in epoxidation of unsaturated compounds with nascent
peroxy acids [8, 9].
Here we report on epoxidation of ﬂ ax oil with nascent
peroxyacetic acid in the presence of chlorinated cation
exchanger KU-2×8 (CKU) as catalyst.
A three-necked ﬂ ask kept at required temperature
was charged with deﬁ nite amounts of acetic acid (AA),
hydrogen peroxide, CKU, and a mixture of ﬂ ax oil with
a solvent (toluene). Then the stirrer was switched on,
and the reaction progress was monitored by variation of
the content of hydrogen peroxide and peroxyacetic acid
(PAA), determined by titration. After the consumption of
the required amount of hydrogen peroxide, the reaction
was stopped and the reaction mixture was transferred into
a separatory funnel in which the lower aqueous layer was
separated from the upper organic layer. In the aqueous
layer, we determined the content of H
, PAA, and AA.
The organic layer was diluted with the solvent and washed
with warm water to completely remove the carboxylic
acid and hydrogen peroxide. The resulting solution of
the oil was transferred into a distillation ﬂ ask, the solvent
was distilled off at a pressure of 20–30 mm Hg, and the
target product was isolated. Then the physicochemical
parameters of the epoxidized flax oil (EFO) were
CKU used as catalyst (chlorine content 9.5 wt %,
exchange capacity 3.54 mg-equiv g
) was prepared by
chlorination of KU-2×8 cation exchanger in the presence
of the HCl + H
system . The performance and
stability of the resin in synthesis of peroxy acids were
demonstrated in .
In the experiments we used a 30% aqueous solution
, pure grade AA, and ﬂ ax oil (FO) with an iodine
number of 154. The epoxy group content and iodine number
were determined by the procedure described in , and
the content of H
and PAA, according to .