Fabrication of highly stable and durable wood materials by modification of polyacrylamide (PAM)-glyoxal (GLY)

Facile and efficient protection strategies to improve wood dimensional stability and resistance to mold and termite are urgently needed in the architectural constructional materials market. In this study, polyacrylamide (PAM)-glyoxal (GLY) system impregnation and thermal curing were used to modify Scots pine wood. The results showed that the average anti-swelling efficacy (ASE) of 160-AGE, 160-AGEP, and 200-AGE modified wood was 36.09 %, 26.67 % and 19.00 % in volume, respectively. Compared with the untreated wood, the modified wood exhibited better mold resistance. Furthermore, the modified wood samples show higher termite mortality and lower mass losses, indicating good termite resistance. Among them, the anti-mold efficacy in 200-AGE was 91.10 %, and the termite resistance rating in 160-AGE was 9.2. The modulus of elasticity (MOE) of the modified wood sample was 16–25 % higher than that of the untreated wood. Obtained by infrared spectrum and electron microscope analysis, the acrylamide polymer penetrates into the wood cell cavities and forms polyacrylamide, which is crosslinked to wood cell wall -OH by glyoxal. This study can prove that the polyacrylamide-glyoxal system modifier has great potential as a modifier to improve the mold resistance and dimensional stability of wood.