It can be seen from Fig. 8 that crystallinity of CMC decreases with the increase of the degree of substitution from 0.21 to 2.41.This phenomenon may be due to broadening or cleavage of hydro-gen bonds by carboxymethyl substitution at the hydroxyl groups ofcellulose [21]. According to Lin et al. [41] higher DS of CMC resultsin decrease in crystallinity up to 1.1 values of DS. After that, thecrystallinity almost disappears. The same trend was observed withour samples.