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Objectives. This study investigated the surface properties and micelle formation of combined stabilizers, which are a mixture of ionic and nonionic surfactants or different nonionic surfactants, to establish a correlation between the composition of stabilizers and the colloidal–chemical properties of direct emulsions obtained in their presence.Methods. The surface tension at the interface between the aqueous solutions of the combined stabilizers with air and toluene was measured using a digital tensiometer. The sedimentation stability of the emulsions was assessed by the volume of the exfoliated water and oil phases for seven days. The particle sizes of the dispersed phase were determined using an Olympus CX3 bright field microscope equipped with a universal serial bus video camera connection. The rheological properties of the emulsions were evaluated using a rotary viscometer.Results. According to the isotherms of the surface tension of aqueous surfactant solutions at the interface with air and toluene at emulsion preparation temperatures of 50 °C and 65 °C, a mixture of nonionic surfactants exhibited a higher surface activity and lower critical micelle concentration at the interface with toluene. The optimal amount of stabilizers providing stability to the compositions for one month was 4 mass % for a mixture of anionic surfactants and nonionic surfactants and 7 mass % for mixtures of different nonionic surfactants. Emulsions obtained in the presence of a mixture of anionic and nonionic surfactants exhibited higher kinetic sedimentation stability values due to the formation of electrostatic and steric stabilization factors in the system. The developed compositions were microheterogeneous systems, the average droplet diameter of which varied within the range of 1.0–5.7 µm. In terms of rheological properties, emulsions were classified as liquid-like structured systems with coagulation structures; the strength of single contacts between particles of the dispersed phase was (1.6–27.0) × 10-10 N. Conclusions. A comparison of the physicochemical characteristics of the compositions obtained in the presence of organic emulsifiers showed that emulsions stabilized using a mixture of ionic and nonionic surfactants, which form mixed adsorption layers, exhibited the best set of properties.

Российский технологический университет, институт тонких химических технологий, г. Москва, Россия, АННОТАЦИЯИзучена адсорбция индивидуальных неионных ПАВ с различной природой функциональных групп и их смесей на поверхности твердых и жидких частиц. В композициях алкилглюкозидоксиэтилированный спирткокамидопропиламиноксид в соотношении 41,5:41,5:17 наблюдается синергетический эффект увеличения величины максимальной адсорбции, толщины адсорбционного слоя и уменьшения площади, занимаемой одной молекулой на поверхности. Плотная упаковка молекул смесей ПАВ в межфазном слое обеспечивает уменьшение размеров частиц суспензий и эмульсий и повышение их устойчивости в дисперсионной среде в процессе очистки поверхностей от загрязнений. ANNOTATIONThe adsorption of individual nonionic surfactants with different nature of functional groups and their mixtures on the surface of solid and liquid particles was studied. In the compositions of alkyl glucoside -ethoxylated alcohol -cocamidopropylamine oxide in a ratio of 41.5: 41.5: 17, a synergistic effect is observed of increasing the maximum adsorption, the thickness of the adsorption layer and decreasing the area occupied by one molecule on the surface. The tight packing of molecules of surfactant mixtures in the interfacial layer ensures a decrease in the particle size of suspensions and emulsions and an increase in their stability in a dispersion medium during the cleaning of surfaces from contaminants.Ключевые слова: неионные ПАВ, смеси ПАВ, адсорбция, синергизм ПАВ, размер частиц, технический углерод, масляное загрязнение.

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