ISSN 1070-4272, Russian Journal of Applied Chemistry, 2007, Vol. 80, No. 2, pp. 346!347. + Pleiades Publishing, Ltd., 2007.
Original Russian Text + A.I. Akhmedov, D.Sh. Gamidova, 2007, published in Zhurnal Prikladnoi Khimii, 2007, Vol. 80, No. 2, pp. 347!348.
Polyfunctional Additives to Oils, Based on Sulfonated Oligomers
A. I. Akhmedov and D. Sh. Gamidova
Kuliev Institute of Chemistry of Additives, National Academy of Sciences of Azerbaijan, Baku, Azerbaijan
Received October 16, 2006
Abstract-Studies in the field of development of polymeric oligoalkenesulfonate additives derived from
sulfonated oligomers and exhibiting multifunctional effect when added to petroleum oils are summarized.
Among the first additives used in motor oils are
various sulfonates prepared by sulfonation of petrole-
um oils, followed by reactions of the resulting sulfo
acids with various oxides or hydroxides of Group II
metals . These sulfonates are used as detergent and
dispersing additives to motor oils.
The functional properties of sulfonate additives
depend on the chemical nature of a petroleum oil be-
ing sulfonated, i.e., on the content of aromatic hy-
drocarbons; such additives do not improve other per-
formance characteristics of petroleum oils. Therefore,
it would be appropriate to replace petroleum oils as
sulfonation substrates with oligomers or cooligomers
of various vinyl monomers. These oligomers, owing
to the nonvolatility, chemical affinity for petroleum
products, and mutual miscibility with them, and also
to the possibility of widely varying their chemical
nature, allow purposeful synthesis of polymeric addi-
tives with prescribed performance characteristics and
are indispensable in functionalization reactions.
The polymeric additives prepared by such proce-
dure not only preserve the main functional character-
istics of sulfonates but also improve the viscosity3
temperature properties of petroleum oils, making
larger their viscosity index. This is a pressing problem
for Baku oils whose viscosity index is low.
This paper summarizes the results of studies per-
formed at the Institute of Chemistry of Additives, Na-
tional Academy of Sciences of Azerbaijan, in the field
of development of polymeric additives based on sulfo-
nated oligomers. The sulfonation was performed both
with oleum and with chlorosulfonic acid. The prod-
ucts were neutralized with various amines, and also
with magnesium or calcium oxide or hydroxide [2, 3].
As starting compounds were used cooligomers of
a-olefins (isobutylene, 1-hexene, 4-methyl-1-pentene)
with styrene, a-methylstyrene, dicyclopentadiene, or
indene, and also cooligomers of vinyl butyl ether with
styrene. Introduction of cyclic fragments into cooligo-
mers creates an additional reaction center for the sul-
fonation and makes the products resistant to oxidation.
Copolymerization of a-olefins and vinyl n-butyl
ether with styrene and of a-olefins with the other
comonomers was performed in the presence of AlCl
at 5320oC; the content of the comonomer units was
10320 wt %; the molecular weight of the binary co-
oligomers obtained was 100032000.
The sulfonation of the cooligomers was performed
by the standard procedure. Depending on particular
requirements, the sulfonation products were neutra-
lized so as to obtain ash-free and ash additives.
The compositions and structures of the compounds
obtained were studied by IR and
H NMR spectros-
copy and by elemental analysis. The presence of aro-
matic fragments was confirmed by the IR absorption
band at 1610 cm
. The content of aromatic units in
the cooligomers was determined by
H NMR spectros-
copy from the integral intensity of signals of the aro-
matic ring protons (d 6.6 ppm).
As the studies showed, a decrease in the molecu-
lar weight impairs viscosity3temperature properties of
petroleum oils and leads to an increased consumption
of the cooligomer for thickening, which is not eco-
nomically profitable. At the same time, additives
with molecular weight exceeding 2000 are less stable
When present in an amount less than 10%, the co-
monomer units in the cooligomer affect the perform-
ance characteristics of the additives insignificantly.
At the same time, at the content of comonomer units