Fire resistance of wood impregnated with soluble alkaline silicates

Abstract

The aim of this paper is to determine the fire performance of wood panels (Araucaria angustifolia) impregnated with soluble alkaline silicates. Commercial silicates based on sodium and potassium with 2.5/1.0 and 3.0/1.0 silica/alkali molar ratios were selected; solutions and glasses were previously characterized. Experimental panels were tested in a limiting oxygen chamber and in a twofoot tunnel. Results displayed a high fire-retardant efficiency using some soluble silicates. Experimental panels were tested in a Limiting Oxygen Chamber (LOI values) and in a Two-Foot Tunnel (Flame-spread index, Panel consumption, After-flaming time and After-glow time). Testing results displayed a high fire retardant efficiency and a minimum thermal expansion of some soluble silicates.