Obtaining and studying the properties of Pickering emulsions of epoxy oligomers stabilized by diatomaceous earth particles

In the presence of diatomaceous earth microparticles, Pickering emulsions of the first kind of epoxy oligomer CHS-EPOXX 530 were obtained. The patterns of change in their rheological properties depending on the oligomer concentration, volume ratio of phases, and content of solid powder stabilizer (diatomaceous earth) were established. In particular, it was found that with an increase in the concentration of the oligomer and stabilizer (diatomaceous earth), there is an increase in interparticle interaction, an increase in the effective viscosity of emulsions, and the formation of a coagulation-thixotropic structure that breaks down under slight shear deformation with the establishment of quasi-Newtonian flow. The nature of the influence of these factors on the physical and mechanical properties of the coatings and films obtained using these emulsions has been established. The data obtained indicate the good film-forming properties of such emulsions and the prospects for their use in various practical applications: as film formers for paint and varnish materials containing a limited amount of organic solvents, non-drying adhesive coatings, and two-component adhesive compositions. In particular, the developed cold-curing adhesive can be recommended for the repair of concrete structures, including bridges, in order to preserve their functional suitability and increase their load-bearing capacity.

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