The possibility of using tris(2-chloroethyl) phosphate, tris(1-chloro-2-propyl) phosphate and tris(4-methylphenyl) phosphate as effective plasticizers for epoxy polymers has been studied. As a result of the research the optimum content of plasticizers (40 parts by mass) has been determined, which has the best effect on the strength and fire safety properties of epoxy composites. Modification of the epoxy polymer with presented plasticizers influences carbonization process increasing char yield and reducing the amount of volatile thermolysis products released into the gas phase, thus improving fire safety parameters of epoxy composites, reducing mass loss on ignition in air from 78 to 2–9% and increasing limiting oxygen index (LOI) values from 19 to 25–31% by volume, giving good fire protective properties to epoxy composites (UL-94 rating—V-0/V-1). The thermo-protective properties and the structure of the char formed by polymer combustion have been studied and the correlation between the thermo-protective properties of the char and the combustibility of the composite has been determined. Furthermore, the behaviour of the modified composite during high rate pyrolysis has been analyzed.

In this study, we used multilayer graphene oxide (GO) obtained by anodic oxidation of graphite powder in 83% sulfuric acid. The modification of GO was carried out by its interaction with hexamethylenediamine (HMDA) according to the mechanism of nucleophilic substitution between the amino group of HMDA (HMDA) and the epoxy groups of GO, accompanied by partial reduction of multilayer GO and an increase in the deformation of the carbon layers. The structure and properties of modified HMDA-GO were characterized using research methods such as scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction spectroscopy and Raman spectroscopy. The conducted studies show the effectiveness of using HMDA-OG for modifying epoxy composites. Functionalizing treatment of GO particles helps reduce the free surface energy at the polymer–nanofiller interface and increase adhesion, which leads to the improvement in physical and mechanical characteristics of the composite material. The results demonstrate an increase in the strength and elastic modulus in bending by 48% and 102%, respectively, an increase in the impact strength by 122%, and an increase in the strength and elastic modulus in tension by 82% and 47%, respectively, as compared to the pristine epoxy composite which did not contain GO-HMDA. It has been found that the addition of GO-HMDA into the epoxy composition initiates the polymerization process due to the participation of reactive amino groups in the polymerization reaction, and also provides an increase in the thermal stability of epoxy nanocomposites.

Zeolite-containing polyfunctional catalysts Fe-Pt/Al2O3 (КТ-17, КТ-18), modified with additives of molyb-denum, phosphorus and cerium, were synthesized. The developed catalytic systems were studied in treatment of C14 alkane obtaining a gasoline fraction. Reaction products contain C4-C9 iso-alkanes, C10-C14 iso-alkanes, C4-C10 alkanes, aromatic hydrocarbons and C1-C3 alkanes. In addition, 0.2–0.6 % of heavy hydro-carbons was found in reaction products. The yield of C4-C9 iso-alkanes at 380 °C reached 37.9 %. By means of physical and chemical methods it has been found that the zeolite containing catalysts Fe-Pt /Al2O3 modi-fied by various additives are complex systems. Micro-diffraction and Mossbauer spectroscopy methods al-lowed detecting nanosized hetero clusters of Fe-Pt, Fe-Mo, Pt-Mo in catalysts structure. Depending on chem-ical composition of clusters, particle size varies between 20 and 80 Ǻ. KT-18 catalyst demonstrates high ac-tivity in the process of heavy alkanes treatment; sizes of platinum (d = 200 Å) and iron (d = 30–50 Å) parti-cles were determined by electron microscopy. Activity of KT-18 catalyst is higher than that of highly dis-persed KT-17. The main feature of KT catalysts is their polyfunctionality. During alkanes processing simul-taneous and consecutive reactions of hydrocracking, dehydrogenation, isomerization, dehydro-cyclization and hydro-desulfurization take place.

As a result of the conducted studies, the method of combining components and foaming parameters for obtaining foam epoxides has been selected. The relationship between the structure of the foam epoxide and the amount of the added blowing agent—ammonium carbonate—has been established. This study explores the development of fire-safe foamed epoxy composites by incorporating technogenic waste from ceramic brick production. The optimized composites demonstrated improved compressive strength, enhanced fire resistance (the LOI—35–44%—and successful UL-94 V-0 testing) through the use of flame retardants (Tris(2-methylphenyl) phosphate and Decabromodiphenyl oxide) and low thermal conductivity (0.030–0.042 W/m K), highlighting their potential as sustainable thermal insulation materials.

Developing polymer composites with improved mechanical and thermal properties requires strategies to overcome the problem of agglomeration and weak interfacial interactions of carbon nanofillers. This paper presents an effective strategy for the covalent functionalization of graphene oxide (GO) with melamine to create high-performance epoxy nanocomposites. The functionalization results in the formation of nitrogen-containing heterocyclic structures on the GO surface, as confirmed by FTIR and Raman spectroscopy. The addition of the obtained modified filler (mel-GO) into the epoxy matrix provides a synergistic effect: the melamine amino groups catalytically accelerate curing, reducing the gelation time from 146 to 48 min and increasing the maximum self-heating temperature from 94 to 122 °C, thus indicating enhanced interfacial interaction. This interaction results in a remarkable overall improvement in mechanical properties: tensile and flexural strengths increase by more than 20%, and elastic moduli by 31% and 58%, respectively, compared to the composite containing unmodified GO. At the same time, impact strength (from 14 to 23 kJ/m²) and hardness (up to 87 Shore D) increase. A key achievement is a dramatic increase in thermal and thermal-oxidative stability: the onset temperature of decomposition (T₅%) increases by 27 °C, the half-decomposition temperature (T₅₀%) by 45 °C, and the thermal stability index (THRI) increases from 119.3 to 128.9 °C. A more than twofold increase in coke residue yield (to 9.29%) and an increase in the Vicat softening point to 175 °C confirm the formation of an effective thermally stabilizing barrier layer due to the combined action of nitrogen-containing groups and dispersed graphene flakes. The proposed approach to functionalizing graphene oxide with melamine opens the way for the creation of next-generation epoxy composites with a record-breaking combination of strength, impact toughness, and thermal stability for applications in aerospace, electronics, and composite structures operating under extreme conditions.

The reserves of liquefied petroleum gas in the production zones and fields are briefly characterized in present paper. The scope of liquefied petroleum gases application, catalytic transformation and their importance in obtaining products are described. Widespread use of nanostructured and nanoscale catalysts in catalysis processes and their properties are given in literature review. Chemical transformations of С3-С4-alkanes in the presence of mono- and bimetallic catalysts based on Cr/SiO2 are studied. By method of electron microscopy, it was determined that various highly dispersed oxides of chromium in lanthanum – modified catalyst interact with each other and with carrier. According to electronic paramagnetic resonance data, chromium is contained in a five- and three-valence state. Mono - and bimetallic catalysts were studied by physical and chemical methods: IR spectroscopy, electron microscopy (EM) using micro diffraction, EPR. Monometallic catalysts with a chromium content of 2-10 wt. % and bimetallic lanthanum-chromium-containing catalyst in the form of 5% La-Cr/SiO2 in a ratio of 1/1 were prepared in the work; the process temperature was varied in the range of 400 to 650°С. Introduction of lanthanum leads to the formation of LaCrO3, LaCrO4 compounds with low activity in dehydro-genation reaction of C3-C4 – alkanes. The maximum yield of C2-C4-olefins - 39.2%, i.e. the formation of propylene in high doses was observed in the presence of 5% Cr/SiO2.