Surface colour and chemical changes of furfurylated poplar wood and bamboo due to artificial weathering

Although furfurylation greatly improves dimensional stability, hardness, and biodegradation resistance of wood and bamboo, the effects of furfurylation on the resistance of wood and bamboo to weathering are still not clear. In this study, poplar wood and moso bamboo were furfurylated and underwent artificial weathering. The surface chemical changes of the control and furfurylated wood and bamboo samples were examined using the attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS). The colour changes were also investigated by measuring CIELab parameters. Results demonstrated that the wood/bamboo surfaces showed decreased lightness and became reddish and yellowish after artificial weathering. Furfurylation endowed poplar wood and bamboo with improved stability of photo-discolouration. Weathering caused remarkable degradation of lignin in the control and furfurylated sample surfaces with decreased aromatic carbons and increased oxygenated carbons. The poly(furfuryl alcohol) in sample surfaces could also be oxidized during weathering. Compared with the furfurylated bamboo, the furfurylated poplar wood had higher stability of photo-degradation.