Permeability is important to ensure the protective properties of coatings based on styrene-acrylic dispersions. This indicator characterizes the complex of insulating properties of coatings, their ability to prevent the penetration of liquids, vapors and gases from the environment to the surface to be protected. It was studied the effect of aluminosilicate microspheres, which are characterized by the hydrophilic nature of the surface and highly dispersed silicate filler aerosil with a hydrophobised surface on the water absorption of styrene-acrylic coatings. Decreased of water absorption of styrene-acrylic coatings filled with aluminosilicate microspheres with the introduction of hydrophobised aerosil is linked to the fact that the fine aerosil with a high specific surface area provides the formation of a more densely packed structure. Thus, partially filling the interspherical space, which is formed by particles of microspheres with a diameter of 10-100 μm and reduces the surface defect of the styrene-acrylic coating. Localization on the surface of defective structures of particles of hydrophobised aerosil leads to a decrease in wetting of defective structures with water. Resulting deteriorating wetting the surface of the styrene-acrylic coating. Micrographs were taken to assess the nature of the distribution of aerosil on the surface of the styrene-acrylic coating. The analysis of the obtained micrographs confirms that the introduction of microspheres form large agglomerates, between which there are vacancies, which will negatively affect the technological and operational properties of the developed coatings. At the same time, the introduction of aerosil allows to obtain a more orderly structure, which allows to obtain a coating with lower internal stresses, increased aggregate stability and, as a consequence, with improved technological and operational properties.

In scientific work is presented the solution of scientific and practical task – the development and evaluation of the possibility of using difficult combustible epoxyurethane (EU) mastic with increased vibration-damping properties and the necessary physical and mechanical properties for cladding the internal metal surfaces of railway rolling stock bodies. The compositions of the developed mastic based on the mixture of oligester cyclo-cab (OCC) and epoxidian (ED) oligomers with the addition of flame retardant – ammonium polyphosphate (APh), as well as hydrophobic filler methylaerosil AM-1-300 to give the composition thixotropic properties. As a result of dynamic-mechanical and viscoelastic researches, it was found that the mastic composition ED: OCC with the content of fire-retardant additive and thixotropic filler has high damping properties (tgδ = 0.45-0.47) in highly elastic field, and therefore, from practical point of view, this the material can work both at low (from -60°C) and moderate temperatures (to +60°C). A comprehensive fire hazard assessment showed that the developed mastic belongs to the group of difficult combustible and difficult flammable materials with slow flame spread and moderate smoke generating ability, as well as moderately hazardous in terms of toxicity. The achieved level of characteristics of the difficult combustible vibration damping mastic testifies about the prospects of its further use for facing the internal metal surfaces of bodies of railway rolling stock in order to ensure their fire safety and acoustic comfort.

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The article presents a solution to practical problem - the development of epoxy coating of low combustibility with corrosion-resistant properties for the protection of glued-laminated timber in conditions of high humidity. Based on the test results obtained, it was found that when using the developed epoxy polymer protective coating, the resistance of wooden beams to distilled and seawater increases by more than two orders of magnitude, ensuring the integrity of wood products and structures, protecting the ends and not causing warping of the material. In conditions of medium aggressiveness of the environment i.e. 10% H2SO4, 10% NaOH, 10% NaCl, the application of the developed epoxy polymer coating to glued-laminated timber provides their high indicators of bio- and chemical corrosion protection (water resistance, resistance to sea water and aggressive aqueous solutions). The developed protective coating has fungicidal properties, protecting structures from the appearance of blue stains, mold and wood-destroying fungi. Revealed a good correlation between the concentration of biocide and fungicidal coating properties. A comprehensive assessment showed that the developed epoxy coatings have increased biocorrosion-resistant properties and can be used as protective coatings for glued-laminated timber structures exposed to mold fungi, high temperatures and high humidity.