Peak (cm-1) Possible assignment Starch Starch-PVA Starch-CS Starch-CS-GA
3274-3420
O-H stretching (Henao, 2018) N-H stretching (Brugnerotto, 2001)
yes
yes
yes (increased)
yes (increased)
2359 -CH2- symmetric stretching (Ghabboun, 2012) no yes no yes (reduced)
1079-1082
C-O-C stretching (Henao, 2018)
yes
yes
yes
yes
1639 C=O bond of amides (Henao, 2018) no no no yes
1551-1556 C=O bond of amides (Henao, 2018) no no yes yes
1409-1410 C-H bonds (Henao, 2018) no no yes yes
1017-1022 C-O stretching (Henao, 2018) yes yes yes yes