STRUCTURAL HETEROGENEITY OF LIGNIN

摘要

Studies on structural heterogeneity of lignin in the past twenty five years were summarized Lignin in the compound middle lamella of hardwood is guaiacyl rich and highly condensed Milled wood lignin (MWL) probably originated from this lignin fraction at least at the short milling time. Endwise lignin fraction was confirmed in periodate lignin of birch wood, which is mainly composed of syringyl unit (ca.90%) and linked by β-O-4 bonds.