The chemical modification of lignins with succinic anhydride in aqueous systems

Chemical modification of oil palm trunk fibre lignin, poplar lignin, maize stem lignin, and barley, wheat, and rye straw lignins was achieved by ester ification with succinic anhydride in aqueous solutions. FT-IR spectroscopy clearly revealed the differences in the structure of the modified lignins a s a result of this succinoylation. These changes were reflected by thermal analyses such as thermogravimetric analysis and differential scanning calor imetry. All the succinylated lignin preparations showed an increased therma l stability compared to the corresponding unmodified lignins. (C) 2001 Else vier Science Ltd. All rights reserved.