Determining the degree of fire retardancy of plywood with thermogravimetry, part I: Beech plywood

Abstract

The basic motive of this work is the ever more pronounced need for fire-resistant plywood. In this work, beech veneers have been impregnated with solutions of chosen fire retardants, which are diammonium phosphate monoammonium phosphate, sodium acetate, water glass, sodium tetra borate and boric acid. To determine the preliminary level of fire retardancy achieved in veneers before manufacturing of finished plywood, thermo gravimetric (TG) and derivative thermogravimetric (DTG) methods are used. TG and DTG analyses of treated and untreated wood, as well as of fire retardants alone, were performed on a Perkin-Elmer TGS-2 thermo gravimetric equipment. Fire resistance of plywood was tested in accordance with standard test for resistance to the effects of fire and the most efficient fire retardants monoammonium phosphate and sodium tetra borate, had the same results as TG/DTG analyses, which points out the validity of TG methods in predicting success of fire retardants in future products.

Keywords

• plywood
• fire retardants
• thermogravimetry
• fire resistance