Russian Journal of Applied Chemistry, 2009, Vol. 82, No. 2, pp. 317−322.
Pleiades Publishing, Ltd., 2009.
Original Russian Text
M.I. Rustamov, N.M. Seidov, Kh.D. Ibragimov, E.G. Mamedbeili, 2009, published in Zhurnal Prikladnoi Khimii, 2009, Vol. 82,
No. 2, pp. 322−328.
AND POLYMERIC MATERIALS
Dimerization of α-Methylstyrene in the Presence of Mordenite,
Aimed at Preparation of Transformer Oils
M. I. Rustamov, N. M. Seidov, Kh. D. Ibragimov, and E. G. Mamedbeili
Institute of Petrochemical Processes, National Academy of Sciences of Azerbaijan, Baku, Azerbaijan
Received June 18, 2008
Abstract—Dimerization of α-methylstyrene in the presence of natural mordenite and its modified form was
studied. The dependence of the yield and composition of the products on the process parameters was found.
Conditions were determined for preparing linear dimers with a high selectivity.
Linear and cyclic dimers of α-methylstyrene are widely
used as plasticizers, as polymer and rubber modiﬁ ers, and
in production of synthetic oils [1–4].
High-purity transformer oils are widely used in the
modern oil-ﬁ lled power systems of electrical equipment,
in hydraulic systems of engineering apparatus, and in
various composite materials as the base of insulating,
cooling, and shock-absorbing ﬂ uids and ﬁ lm-forming
compounds [5, 6]. Therefore, it is important from both
scientiﬁ c and practical viewpoints to ﬁ nd high-performance
synthetic carbon compounds of reproducible composition
and quality that can be prepared on the basis of α-methyl-
styrene dimerization products and meet the existing
Various homogeneous and heterogeneous acid catalysts
are suggested for preparing the dimers: organic and mineral
acids, metal oxides, acid clays, and cation-exchange
resins of various grades [7–9]. In the synthesis of linear
α-methylstyrene dimers, crystalline luminophores were
used as catalysts, and a linear dimer was obtained at
a total α-methylstyrene conversion of 94% . However,
such catalytic systems are unique, and their commercial
use is economically unfeasible. Talzi et al.  prepared
α-methylstyrene dimers using zeolite Y as catalyst. They
showed that the synthesis of linear dimers with a high
selectivity and good yield can be performed in CH
In this study we examined oligomerization of
α-methylstyrene in the presence of natural mordenite and
its modiﬁ ed form without a solvent. We also examined the
possibility of using the dimerization products obtained as
the base for transformer oils.
It is known that dimerization of α-methylstyrene I
yields 2,4-diphenyl-4-methyl-1-pentene (α-isomer) II,
2,4-diphenyl-4-methyl-2-pentene (β-isomer) III, and
1,1,3-trimethyl-3-phenylindan (crystalline cyclic dimer)
IV. The first two compounds are linear unsaturated
dimers, and the third compound is a cyclic saturated
dimer (see the Scheme).
Dimerization of α-methylstyrene I was performed
in the temperature range 30–140°C in the presence
of 5–15 wt % natural mordenite. The effect of various