White pinewood was impregnated with thiourea–formaldehyde (TUF) resin
and orthophosphoric acid (OPA) as a crosslinking agent. The best weight gains (55–
138%) were obtained after impregnation with an aqueous solution of TUF resin for 1 h
and impregnation with aqueous solutions of OPA at different concentrations for 1 h.
Water uptake of treated wood was found to be 23% after a water-soaking test of 168 h,
and a maximum antiswell efficiency was found to be 18% for a 85% OPA solution.
Compression strength of the treated wood also improved with the highest value 62
KN/m2 for wood treated with a 70% OPA solution versus a value of 40 KN/m2 for
untreated samples. Fire retardancy of the treated wood samples was also improved based on concentration of OPA. |
