All FTIR spectra showed quite similar general features, with most of the peaks characteristic of CH films as reported by SilvaWeiss et al.The peaks at 894, 1022, 1060 (C O stretching) and 1149 cm−1 (asymmetric stretching of C O C bridge, glycosidic linkage) were associated with the structure of pure CH, and were
common to all films. The band located at 1378 cm−1 is assigned to the acetamide groups, indicating that CH is not completely deacetylated [51]. The absorption peak at 1647 cm−1 was attributed to C O stretching (amide I), and the one at 1554 cm−1 corresponded to N H bending (amide II)