Table 2. Characteristic FT-IR Peaks for Un-oxidized and Oxidized Natural Rubber.
Sample I.D.
Absorption peak, cm
−1
Chemical structure
Un-oxidized form
3036
=C-H Stretching
2959, 2935, 2854
-CH
3
(Methyl), -CH
2
- (Methylene)
833
cis
-Methine (-CCH
3
=CH wagging)
Oxidized form
1736
-C=O (Aldehyde)
1715
-C=O (Ketone)
1697
-C=O (Interactions with amide of protein)