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The results of studies on the recovery of carbon fibers by the method of low-temperature solvolysis from prepreg and reinforced plastics based on it are reported. The surface of carbon fibers extracted from prepreg and carbon fiber reinforced plastics (CFRPs) was characterized using scanning electron microscopy, thermal analysis, Fourier transform infrared spectroscopy, and Raman spectroscopy to understand their thermal stability characteristics, possible surface chemical composition, and the presence of functional groups. It was shown that in the case of solvolysis of a single-layer carbon fiber, the recoverable carbon fibers contain a smaller amount of undecomposed polymer matrix than in the case of prepreg solvolysis.

The use of mechanochemical activation of the powder at the stage of mixing the components and consolidation by spark plasma sintering made it possible to synthesize material based on silicon carbide, which has a weight loss of less than 0.04% when tested for heat resistance at 1500°C for 100 h. A ceramic material was produced at a consolidation temperature of 1800°C, its hardness was 32 GPa and a critical stress intensity factor was 6 MPa m1/2.

Structurally related poly(amido-o-hydroxy amides) derived from 5,5-methylenebis(2-aminophenol) with tetramethylsiloxane and heteroaromatic (benzoxazole and benzotriazole) fragments incorporated in the second amine component or formed by polyheterocyclization of the corresponding prepolymers were prepared. The effect of modifying fragments introduced into the base poly(o-hydroxy amide) on the heat resistance of powders and films and of films of photosensitive compounds based on the synthesized polymers with the naphthoquinone diazide component was analyzed. The electrophysical parameters of the polymer films and film composites with a nanodispersed ferroelectric filler, (PZT: ceramic powder with the composition Pb0.81Sr0.04Na0.075Bi0.075(Zr0.58 Ti0.42)O3, Russian brand PZT-1), prepared on the basis of modified polymer binders, were determined. Introduction of 20 mol % sulfur-containing fragments into the polymer binder ensures a 50–65˚C increase in the heat resistance for all types of films without increasing the level of the dielectric loss for the composite coatings.

Results of a study of the texture and electrochemical properties of polyaniline—carbon composites used as electrodes supercapacitor are presented. The composites were prepared by polymerization of aniline in the presence of carbon materials with different texture characteristics and monomer content. It was shown that the texture characteristics and electrochemical properties of the carbon/polyaniline composite materials are determined by porous structure of the starting carbon material and by the content of the polymer. The maximum specific capacitance (465 F g−1) was obtained for the composite material based on carbon material with specific surface area of 2290 m2 g−1 and polyaniline content of 61 wt %.

Rheological properties of mixtures of dilute and moderately concentrated aqueous solutions of carboxymethyl cellulose with various degrees of ionization and polyethylene oxide were studied. The range of compositions in which the viscosity of dilute solutions of the polymer blends shows negative deviation from the calculated additive values becomes broader in going from carboxymethyl cellulose sodium salt to partially ionized carboxymethyl cellulose. In concentrated mixed polymer solutions, the deviation of the viscosity from the additive values is always positive. Film composite materials were prepared, and their structural organization and compatibility of the polymers in the solid state were studied by dynamic mechanical analysis and X-ray diffraction analysis. Carboxymethyl cellulose with various degrees of ionization is incompatible with polyethylene oxide in the composite films obtained, and no new mixed structures are formed. Polyethylene oxide behaves as an interstructural plasticizer of the cellulose ether.

A procedure was suggested for preparing brominated polyols of reduced viscosity for the synthesis of foamed polyurethanes of reduced flammability. The flame-retarding action of the synthesized polyol tetrabromophthalate in polyurethane was studied in comparison with that of other widely used flame retardants. Evaluation of the effect exerted on the flammability of the polurethane compound by the polyol tetrabromophthalate synthesized, melamine, and aluminum hydroxide shows that all the samples containing flame retardants are self-extinguishing. The shortest combustion time was observed for the sample containing 6% polyol tetrabromophthalate synthesized. The sample containing as a flame retardant additive solely the synthesized polyole tetrabromophthalate also exhibits the highest performance as a heat-insulating material from the viewpoint of thermal conductivity.

Spark plasma sintering and hot compaction methods were used to obtain experimental samples of a composite material of the SiC‒SiCw system with various modifying additives (AlN, B4C, HfB2, Y2O3, Al2O3, Si3N4). The effect of the modifying additives on the sintering process, physicomechanical, and thermal properties of the ceramic composite material was examined. The introduction of the modifying additives lowered the sintering temperature of silicon carbide produced by the hot compaction method by 200°C and that formed with spark plasma spark sintering by 300‒450°C as compared with the sintering temperature of silicon carbide without additives.

Industrial silicon carbide powder was consolidated with boron by the spark-plasma-sintering (SPS) method. It was shown that a preliminary mechanical activation is a promising method for introduction of high concentrations of boron into silicon carbide. The influence exerted by the boron concentration on the sintering and properties of the material based on silicon carbide was examined. A ceramic based on silicon carbide with 10 wt % amorphous boron was obtained with density of 3.12 g cm–3, hardness of 31.9 GPa, and crack-resistance coefficient of 5.7 MPa m1/2. The ceramic is promising as a construction ceramic for nuclear reactors and gas-turbine engines.