Table 3.
Contributions of the different carbonyl species of the PUU films made with different amino-alcohol chain extenders. Curve fitting of the carbonyl region of the ATR-IR spectra.
| Wavenumber (cm−1) | Percentages of Species (%) | ||
|---|---|---|---|
| PUU-1OH | PUU-2OH | PUU-3OH | |
| 1745 (Free carbonyl-SS) | 30 | 25 | 24 |
| 1738 (Carbonyl-carbonyl interactions-SS) | 11 | 10 | 9 |
| 1726 (Free urethane –SS ether) | 5 | 2 | 5 |
| 1719 (Free urethane-HS) | 11 | 9 | 12 |
| 1706 H-bonded urethane (SS-ether+ SS-HS) | 17 | 11 | 22 |
| 1692 Free urea-HS + H-bonded urethane (SS-HS) | 12 | 10 | 10 |
| 1655 or 1625 (H-bonded urea) | 14 (1655) | 32 (1625) | 18 (1655) |