Southern pine solid wood and wood fiber were reacted with acetic anhydride to various acetyl weight gains. The equilibrium moisture content (EMC) was determined on these specimens at 30%, 65% and 90% relative humidity (RH) and 27 °C. A standard soil block decay test using the brown-rot fungus Gloeophyllum trabeum was performed and weight loss calculated.
Two possible mechanisms have been proposed to explain the resistance of attack of brown-rot fungi on chemically modified wood. One involves the lowering of the cell wall moisture level below that needed for fungal attack. The second involves changing the configuration and conformation of the substrates by modification in such a way that the enzymes can not recognize the substrate. The data presented in this paper indicates that lowering the cell wall moisture level is the major mechanism.
Keywords: Acetylation, brown-rot fungus, moisture, decay
Authors
Rowell R.M.
SP Technical Research Institute of Sweden, Stockholm, Sweden
Professor Emeritus, University of Wisconsin, Madison, WI, USA
Ibach R.E.
USDA, FS, Forest Products Laboratory, Madison, WI, USA
Nilsson T.
SP Technical Research Institute of Sweden, Stockholm, Sweden
Login to download the PDF