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The basic factors influencing the quality of thin films prepared by the spin-coating technique from thermosetting stoichiometric epoxy-amine mixtures have been studied. It has been shown that films 2.5–3.0 nm thick are formed on silicon supports from a 0.025 wt % solution of the stoichiometric mixture of epoxy resin and amine in toluene. Multilayer polymer coatings with thickness up to 40 nm have been prepared from successively deposited partially cured epoxy-amine layers. The thickness of these coatings grows linearly with an increase in the number of layers, while their surface energy decreases. The revealed features may be used for creating multilayer polymer coatings, the properties of which vary along the coating thickness.

The electrophoretic motion of a polyelectrolyte capsule has been considered in a uniform electric field. The capsule carries a uniformly distributed charge and is permeable to ions of different natures. An electrolyte identical to a dispersion medium is located inside the capsule. The flow in the porous layer of the capsule has been described by the Brinkman equations taking into account the effect of electrostatic forces. The distribution of ions in the vicinity of the capsule has been determined, and its electrophoretic mobility has been found in a linear approximation. The mobility of the capsule has been studied as depending on its geometric characteristics, permeability, and charge density. In particular, a complex extremal character of variations in the mobility as depending on the solid phase fraction in the capsule has been revealed at different ratios between the thicknesses of the electrical double layer and the Brinkman filtration layer.

The question of the mechanism of action and the place of application of capillary forces has been discussed. It has been shown that the conventional notions of the character of capillary forces are often contradictory. A molecular-kinetic approach has been employed to determine the places of application of capillary forces and the mechanism of their action.

Nonequilibrium processes have been considered on interfaces between media, with one medium being a permeable membrane. The nonequilibrium processes have been described in terms of nonequilibrium thermodynamics combined with the Fokker−Planck kinetic equation. Phenomenological equations derived within the framework of the combined approach have been discussed. It has been shown that the formal use of linear equations of nonequilibrium thermodynamics may be, in some cases, reduced to nonlinear equations for heat and mass transfer through an interface. It has been noted that the asymmetry of transport characteristics of asymmetric membranes may be explained in terms of the derived relations.

The mechanism for the development of osmotic pressure has been discussed. A simple method has been proposed for deriving an expression for osmotic pressure based on molecular-kinetic considerations. The invalidity of frequently used ideas of osmotic pressure as an additional contribution to the pressure of low-molecular-mass solutes, colloidal particles, or polymer molecules has been noted. It has also been indicated that, in some cases, it is more correct to speak about an osmotic reduction rather than an increase in the pressure. In particular, the Raoult law has been shown to be a direct consequence of the Van’t Hoff law for osmotic pressure.

Nonequilibrium processes occurring at interfaces between media one of which is capable of sorbing have been discussed. The entropy production accompanying the passage of a fluid from a bulk phase to the sorbing medium has been determined. It has been shown that temperature and pressure jumps must take place at the interface, which are commonly ignored when describing the transport in membrane systems. The magnitudes of these jumps upon substance transfer through the sorbing media have been determined.

The problem of a liquid flow, which is uniform at infinity, around a capsule comprising a fractal shell filled with a liquid identical to the ambient liquid has been solved. The flow in the fractal layer is described by the Brinkman equation, assuming that the viscosity of the effective medium differs from the viscosity of the pure liquid. Velocity and pressure distributions have been found, and the viscous drag force applied to the capsule has been calculated.

The problem of local entropy production in gases flowing through nanosized channels has been discussed. The main attention has been focused on the role of adsorbed layers. It has been shown that the local entropy production differs from that obtained in terms of the classical approach. For example, the transfer in the adsorbed layer influences both the entropy production and the form of phenomenological equations. An additional difference results from the mass and energy exchange between the bulk phase and the adsorbed layer, this exchange being related to nonlinear adsorption isotherms. This exchange is described by independent local phenomenological equations.

The problem of a liquid flow that is uniform at infinity around a capsule containing a fractal aggregate is solved. The flow in the porous layer of the capsule is described by the Brinkman equation, assuming that the viscosity of the Brinkman medium differs from the viscosity of the pure liquid. The tangential stress jump condition is imposed on the liquid-porous medium interface. Velocity and pressure distributions are found, and the hydrodynamic force applied to the capsule is calculated.

The methods of nonequilibrium thermodynamics are used to describe the temperature gradientinduced motion of inclusions and the cross effect in solids occurring in the state of premelting. Inclusion motion is caused by a nonuniform disjoining pressure in thin unfrozen interlayers that are formed at a nonuniformly heated inclusion. The cross effect is related to the generation of a local temperature field upon the inclusion motion under the action of an external force in a uniform solid. It is shown that the Onsager relations are valid for the nonequilibrium processes under consideration.

The problem of the infinite uniform flow of liquid around the spherical drop coated with the porous layer is solved. External liquid permeates into the porous layer but is not mixed with the liquid located in the internal cavity of a capsule. The flow inside the porous layer is described by the Brinkman equation; moreover, the viscosity of the Brinkman medium is assumed to be different than the viscosity of pure liquid. The boundary condition of the jump of tangential stresses at the liquid-porous medium interface is used. Velocity and pressure distributions are found and the hydrodynamic force acting on the capsule is calculated. Different limiting cases are considered.

The flow of viscous liquid in a porous model medium with a fractal structure is considered. The hydrodynamic permeability of a medium is calculated according to the Happel and Brenner cell method using Brinkman equations. An analysis is carried out for boundary conditions on the cell surfaces of four types corresponding to the Happel, Kuwabara, Kvashnin, and Cunningham models. Situations that correspond to the flow of viscous liquid in a porous medium formed by fractal aggregates and the uniform flow of viscous liquid around the single composite particle are analyzed.

The problem of a liquid flow that is uniform at infinity around a spherical porous capsule is solved. The flow in a porous layer is described by the Brinkman equation assuming that the viscosity of the Brinkman medium differs from the viscosity of the liquid flowing around. The tangential stress jump condition is imposed on the porous medium-liquid interface. Velocity and pressure distributions are determined and the hydrodynamic force applied to the capsule is calculated.

Adsorption of cationic (dodecylpyridinium bromide) and nonionic (Triton X-100) surfactants from their mixed aqueous solutions on a SiO2 surface at pH 3.6, 6.5, and 10 is studied by the UV spectroscopy, capillary zone electrophoresis, and wetting measurements. It is shown that the adsorption of cationic and nonionic surfactants from mixed solutions is accompanied by synergistic effects manifesting themselves as an enhanced adsorption of both surfactants compared to their adsorption from individual solutions. The effect of second component becomes most pronounced under conditions when differences in adsorption abilities of individual surfactants are rather large (at pH 3.6 and 10). It is shown that the adsorption of surfactants from mixed solutions can be controlled by the adsorption ability of components via the variations in solution pH.

Dependences of the surface tension of aqueous solutions of cationic (dodecylpyridinium bromide) and nonionic (Tween 80, Triton X-100) surfactants and their mixtures on total surfactant concentration and solution composition were studied. The values of critical micellization concentration (CMC) and excess free energy of adsorption were determined from tensiometric measurements. Based on Rubingh–Rosen model (approximation of the theory of regular solutions), the compositions of micelles and adsorption layers at the solution–air interface as well as parameters of interaction between the molecules of cationic and nonionic surfactants were calculated for the systems indicated above. It was established that, in the case of surfactant mixtures with considerable difference in the CMCs, the micelles of individual surfactant with lower CMC value are formed. The effect of negative deviation from the ideality during the adsorption of surfactants from mixed solutions at the solution–air interface was disclosed. It was shown that the interaction energy depends significantly on the composition of mixed systems.

The micellization of the mixtures of cationic (cetyltrimethylammonium bromide, cetylpyridinium bromide) and nonionic (Triton X-100) surfactants at various content of components in aqueous solutions, as well as the adsorption of surfactants at the air/solution interface were studied. The effect of negative deviation from the ideality was discovered during the formation of mixed micelles and adsorption layers. Various theoretical approaches to the quantitative description of mixed systems were compared within the framework of the model of pseudophase separation. The parameters of intermolecular interaction in mixed micelles and adsorption layers, excess free energies of micellization and adsorption, compositions of micelles and adsorption layers were calculated. It was shown that the use of various theoretical approaches for the analysis of interactions in surfactant mixtures leads to close numerical results. It was shown that the composition of mixed micelles and adsorption layers, as well as the parameters of intermolecular interaction and the excess free energy depend on the relative content and molecular structure of surfactants (mixture components).