CARBOXYMETHYLATION OF POLYSACCHARIDES – A COMPARATIVE STUDY

The present study describes the heterogeneous carboxymethylation of xylan,α-1,3-glucan, glucomannan, pullulan, curdlan, galactoglucomannan, and agarose with sodium monochloracetate (SMCA) using iso-propanol as slurry medium in the presence of caustic soda. Using heteropolysaccharides for the carboxymethylation, higher DS values are obtained compared to the DS of homopolysaccharides. The influence of the amount caustic soda in the reaction medium is studied. The characterization of the products obtained is performed by means of 13C-NMR spectroscopy. Carboxymethylation transforms the investigated polysaccharides into water-soluble products.