Table 3.
Summary of functional groups present in FTIR spectra of CS, TPP, CNP°, CGA, and CNP°-GCA.
| Functional Group | Samples | Wavenumber (cm−1) | Transmittance Percentage (%) | Figure 9 Label |
|---|---|---|---|---|
| -OH/-NH2 stretching vibration | CS | 3353.91 | 35.26 | A |
| TPP | 3253.92 | 57.22 | B | |
| CNP° | 3364.97 | 34.74 | C | |
| CNP°-CGA | 3398.61 | 44.97 | D | |
| N-H bending, amide | CS | 1587.00 | 52.24 | E |
| CNP° | 1527.82 | 72.08 | F | |
| CNP°-CGA | 1520.64 | 70.60 | G | |
| Stretching of C=O, amide | CS | 1641.06 | 51.11 | H |
| CNP° | 1630.94 | 52.27 | I | |
| Stretching of P=O | TPP | 1126.89 | 20.92 | J |
| CNP° | 1073.91 | 32.03 | K | |
| CNP°-CGA | 1014.92 | 15.61 | L | |
| Asymmetrical stretching vibration of P-O-P | TPP | 883.70 | 22.73 | M |
| CNP° | 948.77 | 49.86 | N | |
| CNP°-CGA | 949.14 | 41.68 | O | |
| C=O stretching vibration of carboxyl and ester group | CGA | 1687.62 | 17.02 | P |
| CNP°-CGA | 1700.27 | 16.99 | Q | |
| Aromatic ring C=C stretching vibration | CGA | 1439.88 | 49.94 | R |
| CNP°-CGA | 1428.52 | 52.90 | S | |
| Stretching vibration of C-O-C and C-O of carboxyl and ester group | CGA | 1279.45, 1185.17 | 13.86, 10.39 | T |
| CNP°-CGA | 1265.04, 1228.71 | 30.34, 30.00 | U | |
| Bending of C-H and COH | CGA | 1119.50 | 12.37 | V |
| CNP°-CGA | 1163.43 | 31.83 | W | |
| CH aromatic bending | CGA | 810.46 | 53.71 | X |
| CNP°-CGA | 812.13 | 70.81 | Y |