Thin radiata pine veneers were treated with a range of titanium, zirconium and manganese compounds and exposed to natural weathering. Veneer weight and tensile strength losses were used to assess the protective efficacy of the compounds. The oxidative manganese compounds potassium permanganate and manganic acetate restricted both weight and tensile strength loss of treated wood veneers during weathering. FTIR internal reflectance spectroscopy indicated that lignin was retained at the surface of weathered veneers treated with both manganese oxidants. A number of titanates including tetrabutyl and tetraisopropyl titanate enhanced the tensile strength of wood veneers both before and after weathering, perhaps in part due to the complexing of cellulose in wood. Most of the titanates and zirconates were not very effective in restricting weight loss, indicating that they were unable to protect lignin and FTIR internal reflectance spectroscopy of weathered titanate and zirconate treated veneers supported this conclusion. SEM on many of the titanate and zirconate treated wood surfaces showed extensive deposits formed by hydrolysis of the reagents and such deposits may protect the underlying wood matrix from UV radiation.

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