Systematische Untersuchungen der Wirkung aggressiver Gase auf Fichtenholz

In part 2 the effects of the aggressive gases formaldehyde, ammonia, sulfur dioxide and chlorine on lignin and polysaccharides in spruce wood are described. Formaldehyde causes no degradation of lignin and only minor changes in the polysaccharides. The degradation of lignin by NH₃, SO₂ and Cl₂ is increased in varying degrees by a high water content. The cell wall swelling during NH₃ treatment improves the alkali solubility of polyoses. The cellulose structures are attacked at their surfaces by NH₃, SO₂ hydrolytically cleaves polyoses and less ordered cellulose. Chlorine also penetrates the cellulose structures and causes intensive degradation. A high water content of the wood samples impedes this degrading effect of chlorine.