Influence of Substituent Distribution Along a Cellulose Chain on Enzymatic Degradation of Methylcellulose

Abstract

A commercially available methylcellulose (DS 1.9) was treated with cellulase, and the reaction mixture was subjected to gel-filtration. The eluate was divided into four fractions, and each fraction was subjected to a sugar analysis to see compositions of partially methylated sugars and its degree of substitution. Methylcellulose synthesized with methyl iodide in a nonaqueous cellulose solvent (DS 1.6) was also subjected to the same analysis. As a result of the sugar analysis, a higher molecular weight fraction gave a higher DS value, indicating that higher DS regions in methylcellulose are less degraded by cellulase than lower DS regions. Comparison of these two methylcellulose samples revealed that the substituent distribution along a cellulose chain of synthesized methylcellulose is more heterogeneous than that of commercial methylcellulose.