HIGHLY EFFICIENT FIRE-EXTINGUISHING POWDER

Abstract

Fire-extinguishing powders based on ammonium phosphates (FEP) have a high specific fire-extinguishing ability. However, during storage, their technical characteristics deteriorate, which reduces the efficiency to extinguish fire. To solve this problem, the authors have considered a promising direction for improving the technical properties of FEP by using superhydrophobic functional additives based on silicon dioxide particles. The paper discusses methods for manufacturing fire-extinguishing powder using superhydrophobic silicon dioxide particles with different textural and structural properties and apparent contact angles more than 160°. Based on the results of rheological tests, the main characteristics of functional additives (particle size, shape, apparent contact angle) were determined. Their influence on the fire-extinguishing efficiency of FEP was proven. It was shown that the addition of modified silicon dioxide with monodisperse spherical particles (~55nm) into the FEP provides high flowability, superhydrophobicity (apparent contact angel 168°) and low moisture absorption. The developed functional additive made it possible to manufacture FEP that demonstrates the best among analogues characteristics of fire-extinguishing efficiency, moisture resistance and flowability.