Influence of Water and Humidity on Wood Modification with Lactic Acid
Abstract
Impregnation of dry wood with pure lactic acid oligomers (OLAs) followed by heat treatment confers
promising properties to wood because of OLA’s good diffusion, in-situ polymerization and persistence in cell
walls. Treatment provides drastic reduction of the equilibrium moisture content, high dimensional stability
and good durability. The presence of water during treatment has been evaluated. Curing of OLA impregnated
dry wood in humid atmosphere leads to a strong and global degradation of the material. OLA treatment of
wet wood only impacts the water leaching rate negatively. Treatment of dry wood with OLA diluted in water
additionally decreases the biological resistance and is not efficient for decreasing hygroscopicity. Treatment of
dry wood with lactic acid solution leads to a lower polymerization level but confers good properties.