EFFECT OF STEAMING ON THE SOLUBILITY AND STRUCTURAL-CHANGES OF WOOD LIGNIN POLYSACCHARIDE COMPLEX

IR spectroscopy was applied for the structural studies of it situ lign in-poly-saccharide complex of aspen-, beech- and sprucewood in various steaming processes. The absorbance changes of the absorption band at 1760 cm(-1) were found to be connected with splitting of the lignin-xy lan complex, deacetylation of the glucuronoxylan component and ionizat ion of its carboxyl does not reflect the preferential removal of acidi c xylan. In comparison with native wood, all steamed wood samples show increased crystallinity of the cellulose component determined on the base of the absorbance ratios of absorption bands: 1108 cm(-1)/1091 cm (-1), 1430 cm(-1)/1403 cm(-1) and 1459 cm(-1)/1403 cm(-1).