The resistance of repair epoxy composites modified with silicon-containing additives and mineral fillers

New polymer composites with additives and fillers increasing bio- and chemical resistance were prepared. The composites are based on epoxy resin ED-20 modified with silicon-containing additives PDMS-5 and HDK and with mineral fillers Volsky sand and slag Portland cement grade PC 400-D20. The polymer composites are intended for the production of polymer concrete, filled composites, adhesive, repair, and anticorrosion compositions of concrete and reinforced concrete structures. The corrosion and chemical resistance, toxicity and fungicidal properties of developed polymer composites are investigated experimentally. The value of the coefficient of chemical resistance by comparing the ultimate compressive strength before immersion in aggressive media and after 2 months of exposure is determined. All materials demonstrate good corrosion resistance in corrosive inorganic and organic media over a long test period. It is found that the chemical resistance of modified binders and filled composites in acidic and alkaline media increases by an average of 10–15% because of a decrease in the coefficients of sorption, diffusion, and permeability. The non-Fikian behavior of mass absorption over exposure time was observed for all systems under investigation. Biotesting of modified epoxy binders showed a decrease in the toxicity level of binders with silicon-containing additives compared to unmodified samples. The fungal resistance of composites increases with introducing the silicon-containing additives. This is due to an increase in the hydrophobicity of the surface of the samples due to silicon-containing additives and a decrease in the degree of fixation of mold spores on the surface, as well as structural changes and a decrease in the defectiveness of composites. Fungicidal properties appear in the composites filled with slag cement containing the high concentration of metal oxides.