SELECTION OF PRECURSORS OF SAFE SILICA-BASED FIREPROOF COATINGS FOR TEXTILE MATERIALS

Abstract

The selection of the inorganic precursor SiO2 as the main component of the simplified safe technology for obtaining flame-retardant coatings on textile materials was carried out. By thermographic research of organic and inorganic SiO2 precursors, performed on an OD-102 derivatograph under conditions of heating at a rate of 10ºС/min in an air environment, the processes of decomposition of the coating that occur during the action of fire were investigated. Gels based on inorganic precursors produced by industry (silica sol, silica gel) and silicic acid, which was obtained by the exchange reaction of an aqueous solution of sodium silicate of liquid glass and acetic acid, were studied for the comparative characteristics of thermal destruction of coatings. As organic precursors of SiO2, gels of ethyl silicate-32 and methyltriethoxysilane were studied, which were obtained by hydrolysis of organosilicon com-pounds in an acidic water-alcohol medium with subsequent polycondensation of the hydrolysis prod-ucts. The effect of temperature on the nature of thermal destruction of silica gel, silica sol, silicic acid and organosilicon gels of ethyl silicate and methylotriethoxysilane was investigated. It is shown that inorganic precursors differ favorably from organosilicon precursors in terms of the overall thermal ef-fect during their decomposition, mass loss during heat treatment, and the rate of change of this parameter. Considering that, in addition to total mass loss, the increase in mass loss during heating is less than 1 % in compositions based on inorganic precursors, it is possible to use all three types of inorganic precursors, but from the point of view of acidity and safety of impregnation compositions, preference is given to silicic acid obtained by the exchange reaction of silicate sodium liquid glass with acetic acid.