SCANNING ELECTRON-MICROSCOPE AND INFRARED STUDIES OF WEATHERING IN SOUTHERN PINE

Southern pine has been subjected to a variety of artificial weathering conditions and the wood surface analyzed using infrared spectroscopy and scanning electron microscopy (SEM). The effect of light on the weathering process is quite rapid; changes in functional groups on the wood surface, as monitored by infrared spectroscopy, occur within a few hours exposure. Light and water, both acting together, cause the greatest damage to the surface polymer structure, whereas water alone has very little effect on the chemistry of the surface. SEM data, however, show that water has a deleterious effect on the physical characteristics of the surface. Acetylation of the wood under mild conditions serves to protect the surface from the weathering effect of light and water. The extent of weathering is reduced by approximately 50%.