This article presents the results of a study of the particle size distribution (PSD) in aqueous suspensions of eight natural and artificial minerals, including gypsum, limestone, marl, shale, anhydrite, dolomite, bentonite, and cement. The analysis was conducted using sedimentation in a particle size range from submicron to hundreds of micrometers, revealing significant differences in distribution depending on the mineralogical composition. A study of the particle size distribution revealed that samples with narrower distributions, such as anhydrite and bentonite, exhibit high stability and predictable kinetic characteristics, while the polymodal distributions of marl and cement suggest their suitability for use as fillers. The obtained data allow us to predict their influence on the properties of binders, including hydration rate, packing density, pozzolanic activity, and tendency to aggregation. The results may be useful for optimizing technological processes in the development of repair and restoration compounds and binders.

Keywords: particle distribution, size, suspension, binders, sedimentation, colloidal stability, repair and restoration compounds, median, distribution width

The article discusses the surface-active properties of casein and its potential for use as a bioorganic additive in repair and restoration compounds (RRC). An analysis of literary sources confirming the amphiphilic nature of casein, its ability to stabilize interfacial systems and form stable micelles is carried out. The results of an experimental study of the dependence of the surface tension of aqueous solutions of casein on its concentration, carried out by the hanging drop method on a DSA-100 tensiometer, are presented. It is shown that casein effectively reduces the surface tension of an aqueous solution, especially at concentrations of up to 4–5%, which confirms its active adsorption at the phase boundary. Based on the obtained surface tension isotherm, the predicted wettability is considered based on the Young equation. The data obtained emphasize the prospects of using casein as a natural surfactant for creating environmentally friendly and authentic restoration materials that meet the requirements of construction and restoration.

Keywords: casein, surfactants, repair and restoration compounds, surface tension, wettability.

The article considers the influence of surfactants on the physicochemical and technological properties of repair and restoration solutions, mixtures and compositions and the areas of their application. Particular attention is paid to the mechanisms of interaction of surfactants with solid and liquid phases in repair composites, including the processes of hydrophobization and hydrophilization of surfaces, adsorption, peptization and change in the contact angle. The influence of surfactants on the value of water demand, strength, water resistance and frost resistance of binders, mixtures and compositions is described. The parameters determining the efficiency of surfactant application, as well as quantitative estimates of the surface of dispersed components and their effect on the consumption of additives are given.

Keywords: surfactants, repair and restoration solutions, hydrophobization, hydrophilization, wetting, adsorption, rheology, water demand, additives