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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.

Objectives. The influence of the technological additive content and accelerated aging conditions on the surface energy and elastic-strength properties of nitrile butadiene rubbers with an average acrylic acid nitrile content and rubbers based on them were studied in the paper.Methods. The free surface energy of the samples was determined under the standard conditions and in the accelerated aging conditions with the use of the Owens, Wendt, Rabel, and Kaelble method.Results. It was shown that the elastomeric materials surface energy is influenced by surfactants such as rosin and stearic acid, which are typical ingredients of rubber compounds. It was also found that the thermal aging effect on the physical and mechanical properties of rubbers based on nitrile butadiene rubbers depends on the method of rubber isolation from latex and on the nature of the surfactant components in the samples.Conclusions. The analysis of the results obtained shows that the change in the vulcanizates physical and mechanical properties, depending on the technological additive content and the temperature effect, occurs along with a change in the critical surface tension.