Flammability and physical–mechanical properties assessment of wood treated with furfuryl alcohol and nano-SiO₂

Wood polymer nanocomposites were prepared via in situ polymerization of furfuryl alcohol (FA) using nano-SiO₂ as the particulate phase within fast-growing poplar wood. Different amounts of nano-SiO₂ were mixed with an FA water solution, impregnated into the wood and then oven-heated to induce in situ polymerization. Wood physical–mechanical properties, including dimensional stability, hydrophobic properties, surface hardness, compression strength, and modulus of elasticity, were significantly improved by furfurylation. The addition of nano-SiO₂ redeemed the reduction of modulus of rupture in FA-treated wood. Scanning electron microscopy and Fourier transform infrared spectroscopy indicated that the nano-SiO₂ was introduced into the poplar wood and fixed on the cell wall with FA. The contact angle analysis showed FA and 0.5–1.0 % nanoparticles jointly affected the hydrophobic property of the wood surface. In addition, the cone calorimeter results showed an obviously improved flammability and thermal stability of treated wood at 2.0 % nano-SiO₂ addition.