Molding Properties of Alkali Silicate Compositions

The results of research on compositions based on sodium liquid glass and fillers of mineral and organic origin are presented. Materials that can affect the molding properties and thermal transformations of compositions are used as fillers. It was found that the molding properties of the compositions depend on the mineral composition and content of the filler. It is shown that the greatest increase in the viscosity of the compositions is provided by fine mineral fillers, which limit the influence of free and adsorptive water in the composition of liquid glass. The influence of the dispersion of fillers on the rheological properties of compositions is determined. It was found that an increase in the specific surface area of fillers from 350 to 550 m²/kg can increase the structural strength of molding mixtures by 10–30%. To improve the molding properties of compositions characterized by high porosity, it is proposed to use combined fillers: glass boilerplate and organic filler; broken glass and mineral filler containing a pore-forming component (oil shale, gaize, lignite-bauxite, and refuse ore). The expediency of using fillers with a porous structure is shown. Studies of porous compositions have confirmed the advantages of using combined fillers. It is noted that the use of combined fillers contributes to the porization of liquid-glass compositions at low temperatures.