Process for improving dimensional stability and biological resistance of lignocellulosic material

Abstract From the Canadian patent

Reaction of lignocellulosic material with acetic anhydride greatly improves dimensional stability and resistance to biological attack and is according to the, invention, made in the absence of any cosolvent or added catalyst and in a simple way. Partially dried or dry lignocellulosic material is treated with liquid acetic anhydride for a short period of time, the time being adapted to the dimension of the material used. In a following step, any excess anhydride not impregnated into the material is removed. The impregnated lignocellulosic material is then placed in a heated chamber to yield acetylation to a predetermined weight gain. After a short period of time, again adapted to the …