Journal of Chemistry / 2019 / Article / Tab 1

Research Article

Enhancement of Hydrophobicity of Fish Skin Gelatin via Molecular Modification with Oxidized Linoleic Acid

Table 1

Functional group assignment on major absorption bands occurring in the infrared spectra of nonoxidized linoleic acid (LA) and oxidized linoleic acid (OLA).

Wavenumber (cm−1)Type of vibration and functional group
LAOLA

3350–3120Stretching of OH in fatty acid
3600–3200Stretching of OH in aldehyde, peroxide coupled with OH of fatty acid
30093009CH stretching of cis-double bond (=CH)
29542954Asymmetric stretching vibration shoulder of the aliphatic CH3 group
2926, 28542926, 2854Asymmetric and symmetric stretching, respectively, of aliphatic CH2 group
1745Stretching vibration of C=O of aldehyde and ester
17151715Stretching of C=O of fatty acid
16541654C=C stretching vibration
1465, 14581465, 1458Bending vibration of aliphatic CH2, CH3, respectively
14201420Rocking vibration of CH bonds of cis-distributed olefins
1238, 1175–1055Stretching vibration of C-O ester groups
1180C-O-O vibration of hydroperoxide
990–980Bending of C-O of ester overlapping with CH bending of trans-double bond
975975Bending of C-O of acid
723723Overlapping of the CH2 rocking vibration and the out-of-plane vibration of cis-distributed olefins
680680CH bending of cis-double bond