ISSN 1070-4272, Russian Journal of Applied Chemistry, 2014, Vol. 87, No. 4, pp. 419−423. © Pleiades Publishing, Ltd., 2014.
Original Russian Text © N.V. Sautina, K.I. Sitdikova, Yu.G. Galyametdinov, 2014, published in Zhurnal Prikladnoi Khimii, 2014, Vol. 87, No. 4, pp. 424−428.
OF SYSTEMS AND PROCESSES
Study of Phase Transitions in Lyotropic Liquid-Crystal Emulsion
Systems Tetraethylene Glycol Monododecyl
Ether, Water, and Vaseline Oil by the Wetting Angle Method
N. V. Sautina, K. I. Sitdikova, and Yu. G. Galyametdinov
Kazan National Research Technological University, ul. Karla Marksa 68,
Kazan, Tatarstan, 420015 Russia
Received November 28, 2013
Abstract—Phase behavior of emulsion liquid-crystal systems constituted by tetraethylene glycol monododecyl
ether, water, and Vaseline oil was studied by a set of methods. The type of the mesophase and the temperature
range of its existence were determined. It is shown that the wetting method is applicable to identiﬁ cation of phase
transitions in the given lyotropic liquid-crystal emulsion systems.
Thermotropic liquid crystals ﬁ nd application in de-
velopment of various electro-optic devices , whereas
lyotropic liquid crystals (LLCs) widely occur in the living
nature. It is known that liquid-crystal properties are exhib-
ited by lipids, viruses, biopolymers, and membranes [2,
3]. Therefore, LLCs have been recently used in medicinal
and cosmetic preparations to deliver useful substances to
cells of an organism [4–7].
One of promising areas in medicine and cosmetics
is to use emulsions of the surfactant/water/oil type as
nanosize carriers for immobilization of vitamins, e.g.,
ascorbic acid [8–10]. This is so because lamellar liquid
crystals (LCs) stabilize the system by a gel network. In
cosmetic preparations, LC phase form a multilamellar
lipid structure and, therefore, the product has a high af-
ﬁ nity for skin and favors its regeneration [11, 12].
A number of studies concerned with the phase behav-
ior of three-component systems of the surfactant/water/
oil type have been carried out [13–16]. The formation of
a lamellar mesophase of diphilic diauryl-β-cyclodextrine
and its further incorporation into the structure of the
horny layer of skin for delivery of water-insoluble use-
ful substances have been analyzed . These systems
are widely used in lipsticks  and shampoos. Owing
to the mesogenic structure of a shampoo, the deposition
efﬁ ciency of silicone conditioning ingredients on colored
hair increases . Consequently, synthesis and study of
three-component LC systems are highly topical.
The phase transition plays an important role because
the useful substances being transported are released from
the mesophase in disintegration of the supramolecular
organization of lyotropic LCs . The phase behavior
of liquid crystals is commonly studied by the method of
differential scanning calorimetry (DSC); however, this
technique has limitations in the case of lyotropic LCs.
For example, the phase transition from the hexagonal to
the lamellar phase is not determined by the DSC method
for the system exhibiting a lyotropic polymorphism .
When making formulations of cosmetic preparations,
it is necessary to take into account phenomena occurring
at the phase boundary: wetting, adhesion, spreading.
These phenomena strongly affect the adhesive interac-
tion of a cosmetic preparation with skin and a packaging
material. One of techniques making it possible to assess
these phenomena on the microscopic level is the method
that measures the wetting angle . In the case of an
analysis of phase transitions on a Kruss Easy Drop DSA
20E installation, the advantage of this method over those