Using controlled radiolysis of melamine to reinforce melamine-urea-formaldehyde resin impregnated wood

The effect of electron beam (EB) irradiation (0 to 80 kGy) on the mechanical properties of melamine-urea-formaldehyde (MUF) impregnated wood prepared from Pinus sylvestris is investigated. The results of the compressive strength parallel to grain measurement demonstrate EB irradiation can enhance the mechanical properties of MUF impregnated wood, with optimal results achieved at 20 kGy. Additionally, the formaldehyde emission of impregnated wood has been significantly reduced. This enhancement is promoted by the dispersibility and crosslinking efficiency of melamine in the dealkylation stage under low-dose irradiation. However, the deamination and the destruction of triazine ring becomes significant at higher irradiation dosage, resulting in deterioration of mechanical properties as demonstrated by Raman spectroscopy,C-13-NMR, and SEM.