Acetylated wood composites from

Okino and co-workers produced composites from acetylated rubberwood (Okino etal., 2001) and acetylated cypress (Okino etal., 2004), bonded using a UF resin. The composites exhibited inferior mechanical properties compared to those produced from unmodified wood. The reduction in mechanical properties is undoubtedly due to poor wetting and weak interaction of the surface of the modified wood with the UF resin due to a reduction of H-bonding sites on the acetylated wood surface. 

Four different methods (vapour-phase acetylation using acetic anhydride, acetylation using ketene gas, liquid phase acetylation using acetic anhydride/xylene, or neat acetic anhydride) were used to acetylate pine wood chips to a variety of WPGs for the production of MUF-bonded particleboards (Nilsson etal., 1988). Composite boards were exposed to unsterile soil in fungal cellar tests. Boards made from ketene acetylated chips were not found to be resistant to decay at the maximum WPG level achieved (17 %) with a liquid acetic anhydride modification, no decay was recorded at a WPG level of c. 18 % after 12 months exposure, whereas with a vapour-phase treatment at the same WPG, evidence for decay was found. 

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