Fire Resistance, Hygroscopicity and Water Absorption of Pinus yunnanensis Wood After Impregnated with Wax Emulsion

After pine wood was impregnated with antiflaming wax emulsion at normal pressure, oxygen index and smoke density were selected to investigate the fire resistance of pine wood impregnated with wax emulsion, and Fourier transform IR spectroscopy （FTIR） was also used to analyze the chemistry background of impregnation. Properties including antileaching, hygroscopicity and water absorption of impregnated wood were also investigated. Fire resistance of pine wood was downgraded to be easytoburn material from burnable material after impregnating with wax emulsion. However, addition of flame retardant upgraded the fire resistance of impregnated wood to be hardtoburn material. FTIR spectrum test result showed that the flame retardant material in wax emulsion might be crosslinked to cellulose by amino replacement and ester exchange reaction, which make NH2 graft onto furan molecules, B and P chemical elements in the form of boric acid ester and phosphate graft on wood. Antileaching test showed that flame retardant emulsified wax was leachable, but the fire resistance would not be downgraded after 30 d leaching test. Impregnation with wax emulsion would decrease hygroscopicity and water absorption of pine wood, but no obvious effect of the addition of flame retardant was observed.