Stable and durable wood products based on molecular modification

Abstract

Stable and durable wood products can be produced by chemical modification at the molecular level. One modification that is effective in achieving these properties is by reacting both hardwoods and softwoods with acetic anhydride. The reaction takes place in the most accessible hydroxyl groups in the cell wall polymers. Lignin reacts the fastest followed by the hemicelluloses. Both are highly substituted. As the level of bonded acetyl increases, dimensional stability increases and attack by fungi decreases. The threshold of fungal resistance is approximately 18% acetyl. The moisture in the cell wall may be too low to support fungal growth. This is a summary of several independent projects on the mechanism of property enhancement that were previously published in proceedings.

Citation

Rowell, R.M.; Ibach, R.E. 2018. Stable and durable wood products based on molecular modification. Journal of Tropical Forest Science. 30(5): 488-495. https://doi.org/10.26525/jtfs2018.30.5.488495.