Synthesis and Application of Hydrophobic Silicon Dioxide to Improve the Rheological Properties of Strovite-Based Fire Extinguishing Agents

The rheological characteristics of struvite-based fire extinguishing powder mixtures are comparatively analyzed when using hydrophobic silicon dioxide as a functional filler, obtained during a single-stage synthesis by various methods. Infrared spectroscopy, scanning electron microscopy, low-temperature nitrogen sorption–desorption, and other methods are used to investigate the influence of the synthesis method on the textural and structural properties of hydrophobic functional fillers of fire extinguishing powder mixtures. It is revealed that the key factor affecting the rheological properties of such mixtures is the uniform distribution of the functional filler over the surface of the particles of a fire extinguishing component (struvite). It is proven that the struvite-based powder composition and the developed functional filler are highly effective for fire extinguishment.