The results of this study confirm the possibility of the directional regulation of operational properties of epoxy composites by the use of small additives of hexagonal boron nitride (h-BN), providing the creation of epoxy composites with high performance properties. The effectiveness of h-BN surface modification by γ-aminopropyltriethoxysilane and the formation of strong chemical bonds at the polymer matrix/filler interface has been proved, which ensures an increase in physico-mechanical characteristics of epoxy composites: bending stress increases by 142% and bending modulus increases by 52%, strength increases by 53% and tensile elastic modulus increases by 37%, toughness increases by 400% and Brinell hardness increases by 96%, compared with an unfilled plasticized epoxy composite. Research in the field of polymer modification with functional additives is widely used to create polymer materials with a given set of consumer characteristics. So, to give polymer composite materials and products made from them enhanced functional characteristics, various modifying additives are used, for example, graphite, CNTs, TEG, graphene or metal oxides 1-14. The use of nanocomposites is determined by their unique properties, which are due to the huge specific surface and high surface energy of nanoparticles. Nanometer particles, unlike microand larger inclusions, are not stress concentrators, which contributes to a significant increase in the mechanical properties of nanocomposites 1-3,7. However, the addition of nanomaterials into epoxy compositions only slightly increases the strength of composites and in some cases even decreases it. This is due to small adhesion between nanomaterials and the polymer matrix and to the fact that it is often energetically more profitable for nanomaterials to agglomerate with each other. As a result, to improve adhesion interaction with the polymer matrix and to improve dispersion (reduce agglomeration) hardening nanomaterials are modified in various ways: by plasma treatment, by acid treatment, amines, etc. 6-9. A promising method of surface modification of nanomaterials is direct fluorination, i.e. the effect of fluorine gas mixtures at temperatures from room temperature to 400-500 °C. Fluorination also leads to improved solubility of nanomaterials in various solvents. The effect of CNTs modified by direct fluorination on the properties of epoxy composites was shown in 7. The addition of 0.1 mass % fluorinated CNTs improves physical and mechanical properties: 50% increase in strength and 74% increase in modulus of elasticity during tension, 60% increase in strength and 66% increase in modulus of elasticity during bending, and besides, abrasive wear decreases by 33%. In this research 6 , aminopropyltrimethoxysilane was incorporated as an interfacial modifier on the surface of graphene (Gr) nanoplatelets. The addition of functionalized Gr enhanced the tensile strength and strain to failure only at low contents (i.e., 0.05 wt%). Besides, this decreased the coefficient of friction and wear rat...

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In this article, amino functionalized multiwalled carbon nanotubes (MWCNTs) were prepared by chemical modification of the surface of a MWCNTs using γ-aminopropyltriethoxysilane (APTES) and dispersed into the epoxy composition. The modifying agent (APTES) was directly deposited on the MWCNTs surfaces. For the functionalization of MWCNTs, was used not the APTES concentrate, as it had been described in previous works, but its freshly prepared aqueous solution. Properties of APTES-treated MWCNTs were characterized by transmission electron microscope (TEM), Raman spectroscopy and FT-IR. The results showed that the functionalization and chemical compatibility of APTES-treated MWCNTs with epoxy composition provides their best dispersion in the epoxy composition, had important influence on curing behavior, structure and physicochemical properties of the epoxy composites plasticized with trichloroethyl phosphate. The results showed that the functionalization and chemical compatibility of APTES-treated MWCNTs with epoxy composition provides increased of physicomechanical properties of epoxy composites: bending stress increases by 194% and bending modulus increases by 137%, the tensile strength increases by 108% and the tensile elastic modulus increases by 52%, impact strength increases by 300%, in comparison with plasticized epoxy composite that does not contain MWCNTs.

The possibility of using graphene oxide as a modifying additive for polymer fiber-reinforced composites based on epoxy resin and basalt roving has been studied. The content of graphene oxide in the system has been experimentally selected, which has the best effect on the physico-mechanical properties of the obtained polymer composite material. The efficiency of the modification of the graphene oxide surface with APTES finishing additives and aminoacetic acid, which provides chemical interaction at the polymer matrix–filler interface, has been considered. The influence of graphene oxide and functionalizing additives on the polymer curing process was investigated using the thermometric method and differential scanning calorimetry.

The conducted studies have proven the possibility of the directed control of operational properties of epoxy composites, due to the addition of finely-ground ocher into their composition, and the use of microwave modification of the epoxy composition. The rational content of ocher as a modifying additive (0.5 parts by mass) and a filler (75 parts by mass) of the epoxy composition has been selected, which ensures the improvement of the studied complex of physical-mechanical properties. It has been proven that ocher affects the structure formation processes and the structure of the epoxy composite, thus increasing its thermal, heat and fire resistance. During the research, the application efficiency has been proven, and the optimal parameters of the microwave modification (power—350 W; duration—30 s) of epoxy compositions filled with ocher, which increase physical-mechanical characteristics of composites, have been selected.