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Temperatures have been identified in the corona hood and streamer of a plasma-chemical reactor during the formation of a polymer film with carbon nanosized particles. A semiempirical procedure has been proposed to estimate these temperatures. It has been shown that in the case where the temperature in the streamer volume is ~600°C and it is ~1400°C in the corona hood, polycrystalline carbon nanoparticles are formed in the plasma-chemical reactor whose agglomerates penetrate into the polymer film.

The results of studies into the influence of the thickness of a polystyrene shell applied to surfaces of dispersed corundum (Al2O3) filler particles on the structure and mechanical properties of the composition of an acrylonitrile butadiene styrene plastic are presented. It is shown that the mechanical properties of the composition depend at least on two factors: the interaction between shell molecules and the polymer matrix, and the ratio of shell thickness to the average size of submicron particles of the filler. The change in the mechanical properties of the composition is explained by the decreasing mobility of polymer macromolecules near the encapsulated filler particles due to the increasing adhesion of macromolecules to the polymer shell. It was shown experimentally that the Martens hardness, elastic modulus, tensile strength, and rupture strain can be changed in some range by varying the thickness of the polymer shell on the surfaces of corundum particles.

MCM-41 type mesoporous silica particles were obtained using a template method in an alkaline medium and cetyltrimethylammonium bromide as a matrix. The structural and adsorption characteristics of the mesoporous material were studied by dynamic light scattering, scanning electron microscopy, low-temperature adsorption—desorption of nitrogen, IR spectroscopy, and simultaneous thermal analysis. It was shown that the obtained mesoporous material possesses high porosity with the specific pore volume in excess of 1 cm3 g−1. It was established that the size of silica particles does not exceed 200 nm, which is a value acceptable for the penetration of drugs through cell membranes. The optimal compositions of aqueous dispersions of MCM-41 with minimal sedimentation processes were determined. A drug (indomethacin) was encapsulated into the silica pores using the precipitation method at various temperatures (40 and 60 °C), the quantitative parameters of loading efficiency were calculated. The infl uence of temperature on the encapsulation ability was demonstrated.

A technique for measuring the internal stresses in polymer films deposited on a glass substrate in gas discharge plasma is developed. Using this technique, the dependence of internal stress in thin films of polymethylmethacrylate and polystyrene on the deposition time and the current density of the barrier discharge at atmospheric pressure is studied. It is found that, when forming thin polymer coatings from monomers with high polymerization efficiency, the average value of internal stresses is higher than that for coatings obtained from monomers having low polymerization efficiency in barrier discharge plasma at atmospheric pressure. This can be explained by an increase in the specific number of cross-links in the first type of films under the action of ultraviolet radiation from the plasma. The quasi-optimal deposition time of the polymer film coating from styrene is found in which the value of the internal stress is minimal at a film thickness acceptable for a number of practical applications.

—We study the formation mechanism of carbon nanoparticles with simultaneous formation of a polystyrene film in a AC barrier corona discharge at atmospheric pressure. The importance of the research stems from the need to control the allotropic form of carbon nanoparticles, which affects the physical and technical characteristics of polymer films obtained by this method. It is shown that nucleation of polycrystalline onion-like carbon nanoparticle agglomerates is the basis for graphene flake formation in the corona sheath. Graphene flakes form from these nucleation sites in gas discharge streamers owing to the destruction of monomer molecules remaining in the agglomerates of nucleation sites. It was revealed that the allotropic form of such particles is determined not only by the energy—in this case the barrier corona discharge—but also by the ratio of the duration of its exposure to the characteristic destruction and formation times of covalent bonds participating in the particle process.

The structure and mechanical properties of a composition on the basic of polycarbonate filled with three types of dispersed particles (submicron corundum, micron boron nitride, and glass fiber ones) were investigated. It is shown that the method of sample preparation proposed ensures a uniform distribution of filler particles in them. Slight changes in the supramolecular structure of polycarbonate were seen only in the case of introduction of submicron corundum particles. No such changes occurred in the case of micron boron nitride or glass fiber particles in amounts providing an optical transparency no less than 70%, which can be explained by insufficient interaction forces between filler particles and polycarbonate molecules. It is shown that filling polycarbonate with various fillers allowing the retention of its optical transparency does not make it possible to increase its wear resistance and softening temperature. The weight parts of dispersed filler at which the transparency does not decrease below 70 % are ~0.06, ~0.03, and ~1.0% for corundum, boron nitride, and glass fiber particles, respectively.

The results of experimental studies of anti-acing property of passive organosilicon coatings with hydrophobic groups are presented. The high efficiency of that coating with hydrophobic groups -CF3 is found. It is shown that such coatings can provide low icing intensity and, at the same time, high abrasion resistance.

The influence of the nature of stabilizing amphiphilic additives on the dispersion and precipitation of carbon nanoparticles was evaluated. The stabilized systems were tested for adsorption properties with respect to spectral probes and drugs for which purpose the degree of removal and the amount adsorbed were determined spectrophotometrically for dye Orange OT and anti-inflammatory drug indomethacin.

The physical mechanism underlying the effect of generation of Auger duplexes as a consequence of the electronic level transformation in the case of local energetic effect in the atoms of complex oxides is suggested. It has been established that the effect of the formation of Auger duplexes is independent of the type of radiation acting on an object and is determined by the energy of the affecting particles and by the time of irradiation leading to accumulation of the reactions induced by electrons (ions).

The formation mechanism of argon clathrates with carbon dendrites obtained in the plasma of an atmospheric-pressure gas discharge has been studied. It has been shown that the formation of these clathrates is due to the difference between characteristic times: the lifetime of molecules surrounding argon atoms and the time of C–C bonding. It has been noted that argon clathrates with carbon dendrites can form only if a number of conditions are met: formation of molecular traps in the discharge, provision of a sufficiently low temperature at the center of the arc discharge, and the presence of active carbon particles arising from plasma decomposition of hydrocarbon precursors. Whether or not these conditions are met depends primarily on the composition of the initial hydrocarbon mixture and discharge current density, as follows from experimental data.

The technique of deposition of polymer films from the barrier gas discharge plasma on top of dielectric substrates is developed. The film precursor is a monomer material highly dispersed in a transport plasma gas. The plasma formation of the continuous polymer film can be divided into two stages. The first stage is deposition of liquid monomer droplets with subsequent polymerization on the dielectric barrier surface resulting in growth of a discontinuous film. It is found that the ratio of the height of droplets to their lateral size is almost constant and for polystyrene it is equal to ~0.01. The second stage is expansion of the droplets into islands and their coalescence into a continuous polymer film on the dielectric barrier surface. The polymer coating thickness and the amount of cross bonds essentially depend on the current density and concentration of the monomer in the transport discharge gas. A continuous polymer film, which is not contaminated with the monomer destruction products, can be obtained in the current density range of 7–25 mA/cm2. Experiments with several monomers, like methylmethacrylate, styrene and acrylonitrile, have shown that the growth rate is maximal for monomers with oxygen-free molecules. At the same time, a higher growth rate provides low cross-bond coatings, whereas to get high density of the cross-linked bonds one has to utilize low deposition rates. The minimal thickness at which continuity of the film is achieved increases when the monomer concentration in the plasma rises. In general, the coating thickness depends linearly on the discharge current density; the particular figures depend on the type and concentration of the monomer. The technological parameters are established and given for the three aforementioned monomers.

The structure and mechanical properties of composites based on an ED-20 epoxy resin, modified with ZnO and ZnO particles untreated or encapsulated in polystyrene, were studied. It is shown that the introduction of polystyrene-encapsulated ZnO submicroparticles into the epoxy resin changed its supramolecular structure in comparison with that of the resin filled with untreated ones. It was established that the presence of shell on the filler particles affected the mechanical properties of the polymer composites — their hardness increased by 22.5% and elastic modulus by 13%.

The influence of growth conditions on the carbon dendrite structure has been investigated. The threshold values of the ratio between electron temperature Te and kinetic temperature T of the gas near a needle electrode and of the discharge current density, which are necessary for dendritic growth, have been determined. It has been shown that the hexagonal structure of submicron carbon particles arises when a number of hydrocarbons are used to synthesize dendrites. It has been found that the degree of order in the carbon structure can be controlled by applying external actions at the stage of graphite particle nucleation. The characteristic frequencies of inertial actions that may be energetically appropriate must exceed 10 kHz.

Results of theoretical and experimental investigations of the efficiency of an integral electrothermal anti-ice system based on fluoroplastic films are presented. It is shown that the use of this system makes it possible to decrease the energy expended for the de-icing by 30% as compared to the existing electrothermal anti-ice systems and that an integral electrothermal anti-ice system can be used in small and midget aircrafts including unmanned ones.

In the work we give the results of an experiment during which carbon dendrite structures were formed in the plasma of an atmospheric-pressure gas discharge by using depolymerization products of polymer materials.

This article presents the results of experimental studies of polymer shell formation on the surface of submicron (including nano-) particles due to mixing of a pair of two-phase gas flows of submicron particles and fine-dispersed liquid monomer droplets. The possibility of changing the polymer shell thickness on the surface of submicron particles by controlling the ratio of charges and particle sizes due to variations of electrical field strength in discharge cameras for charging and the dispersion of submicron particles and fine-dispersed liquid monomer droplets is shown.

This work presents the results of experimental tests of a synthesis method of multilayer polymer films with given physicochemical properties of individual layers and determination of the type of bonds between binder-layer molecules and surface molecules of glued polymer films. Thus, for initiation of the reaction of radical surface graft polymerization, the corona discharge was used.

Conditions in which fractal carbon structures are formed in barrier-discharge plasma under atmospheric pressure to obtain submicrometer carbon particles have been studied.

Parameters of external inertial actions capable of stabilizing a fractal oscillator so as to ensure a required regime (mode) of its dynamic behavior are determined. It is shown that the restoring force in the nonlinear fractal oscillator under consideration depends on the square amplitude of the external harmonic action and on an alternating-sign factor.