Russian Journal of Applied Chemistry, 2012, Vol. 85, No. 3, pp. 401−406.
Pleiades Publishing, Ltd., 2012.
Original Russian Text © V.R. Khairullina, A.Ya. Gerchikov, R.M. Akhmetkhanov, I.T. Gabitov, R.T. Minniyanova, A.B. Safarova, I.Yu. Chukchieva, A.V. Kuchin,
2012, published in Zhurnal Prikladnoi Khimii, 2012, Vol. 85, No. 3, pp. 427−432.
AND INDUSTRIAL ORGANIC CHEMISTRY
Antioxidant Properties of Some 4-,6-Methyl-substituted
Derivatives of Isobornylphenol
V. R. Khairullina
, A. Ya. Gerchikov
, R. M. Akhmetkhanov
, I. T. Gabitov
, R. T. Minniyanova
A. B. Safarova
, I. Yu. Chukchieva
, and A. V. Kuchin
Bashkir State University, Ufa, Bashkortostan, Russia
Institute of Chemistry, Komi Scientiﬁ c Center, Ural Branch, Russian Academy of Sciences,
Syktyvkar, Komi Republic, Russia
e-mail: firstname.lastname@example.org, email@example.com, firstname.lastname@example.org
Received March 22, 2011
Abstract—Antioxidant properties of technical-grade mixtures containing 4, 6-methyl-substituted derivatives of
isobornylphenol were studied. The antioxidant activity of samples was characterized by the inhibition rate con-
. The effect of isobornylphenol on the kinetics of inhibition of the thermooxidative dehydrochlorination
of poly(vinyl chloride) plasticized with dioctyl phthalate was examined.
Isobornylphenols constitute a promising class of sta-
bilizers primarily used to preclude oxidative transforma-
tions in medicinal materials, food packages, baby toys
because of their low toxicity and high thermal stability.
Therefore, studies of quantitative characteristics of the
efﬁ ciency of antioxidants are necessary for prediction of
their application prospects [1–7].
The goal of our study was to quantitatively examine
the antioxidant activity of technical-grade mixtures
based on 4, 6-substituted isobornylphenol derivatives
and their effect on the thermooxidative destruction of
The chemical composition of terpene phenol
(TP) samples and UV spectroscopic data obtained in
1,4-dioxane are listed in Table 1. It is known that TP1,
TP2, TP4, and TP5 samples are technical-grade mixtures
of dialkylated isobornylphenols, whereas sample TP3 is
99% pure . All the samples are characterized by IR,
C NMR spectra .
We studied the antioxidant activity (AOA) of TP1–
TP5 mixtures of isobornylphenol in a model reaction
of initiated oxidation of 1.4-dioxane by the method of
kinetic photometry, as judged from the variation with
time of the concentration of the antioxidants under study
at a temperature of 348 K [2, 8]. Azobisisobutyronitrile
(AIBN) served to initiate the oxidation process .
Experiments in which the AOA was studied were
performed at an initiation rate V
= 2 × 10
a thermostated cuvette placed in the cuvette compartment
of a Shimadzu UV-2401 PC spectrophotometer. Kinetic
curves of substance consumption were recorded by
measuring the decrease in the optical density at the
maximum absorption at λ
(nm) of 282 for TP1, 274
for TP2, 283 for TP3, 283 for TP4, and 289 for TP5.
The numerical values of the consumption rate V
compounds TP1–TP5 were calculated by the least-
squares method from the initial portion of the kinetic curve
describing the consumption of the samples under study.
1,4-Dioxane was preliminarily puriﬁ ed by the standard
procedure . The initiation rate V
was calculated by
the equation V
[AIBN], where k
is the initiation rate
). When calculating the initiation rate, we
assumed that k
, where k
is the rate constant of
AIBN decomposition, and e is the probability of exit
of radicals into the bulk. Calculations of k