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| The weathering stability of wood during long-term exposure to outdoor atmosphere is an important issue. Topcoat is one of the crucial methods for protecting wood polymer substrates from environmental factors, such as solar radiation and moisture. In the present study, titanium dioxide (TiO2) coating was synthesized on wood surface using the hydrothermal method to improve its weathering resistance capability. Both the TiO2-coated and control wood were exposed to artificial accelerated weathering for 40 circles (nearly 1 000 h). Color measurements were conducted at intervals throughout the test period, and presented in ΔL*, Δa*, Δb*, and overall color changes (ΔE). Results show that the TiO2-coated wood had better color stability than the control wood. This demonstrates the ability of TiO2 coating to retard color change in wood. Furthermore, the stimulus and opalescence of TiO2 resulted in a whitening effect on the wood after 100 h of exposure. The compositional changes on the wood surface were characterized via Fourier transform infrared spectroscopy. The differences in absorption intensity at 1640 and 1375 cm?1 between the TiO2-coated and control wood suggest the positive contribution of the TiO2 coating to the compositional stability of lignin during the weathering aging process. |
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| Keywords:wood; accelerated aging; coating; weatherability; titanium dioxide |
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