Table 4. Central composite design experiments and experimental results.
| Runs | Independent variables in coded form |
Independent variables in their natural form |
Tgel value (°C) | |||||
|---|---|---|---|---|---|---|---|---|
| 407 (%) |
188 (%) |
HPMC (%) | 407 (%) |
188 (%) |
HPMC (%) |
Predicted | Actual | |
| 1 | 1.0 | 1.0 | -1.0 | 22.8 | 6.6 | 0.3 | 30.4 | 29.4±0.1 |
| 2 | -1.0 | 1.0 | -1.0 | 19.2 | 6.6 | 0.3 | 41.8 | 41.9±0.3 |
| 3 | 0.0 | 0.0 | -1.6818 | 21.0 | 4.5 | 0.1 | 31.9 | 31.8±0.2 |
| 4 | 1.0 | -1.0 | 1.0 | 22.8 | 2.4 | 0.8 | 24.4 | 24.3±0.3 |
| 5 | 0.0 | 0.0 | 1.6818 | 21.0 | 4.5 | 1.0 | 30.4 | 30.5±0.2 |
| 6 | 1.0 | -1.0 | -1.0 | 22.8 | 2.4 | 0.3 | 25.4 | 25.2±0.1 |
| 7 | 1.0 | 1.0 | 1.0 | 22.8 | 6.6 | 0.8 | 29.9 | 28.6±0.3 |
| 8 | -1.6818 | 0.0 | 0.0 | 18.0 | 4.5 | 0.6 | 41.5 | 40.0±0.2 |
| 9 | -1.0 | 1.0 | 1.0 | 19.2 | 6.6 | 0.8 | 41.0 | 41.1±0.3 |
| 10 | -1.0 | -1.0 | 1.0 | 19.2 | 2.4 | 0.8 | 33.0 | 34.0±0.2 |
| 11 | 1.6818 | 0.0 | 0.0 | 24.0 | 4.5 | 0.6 | 24.7 | 26.2±0.1 |
| 12 | 0.0 | 1.6818 | 0.0 | 21.0 | 8.0 | 0.6 | 38.5 | 39.7±0.3 |
| 13 | -1.0 | -1.0 | -1.0 | 19.2 | 2.4 | 0.3 | 34.2 | 35.4±0.2 |
| 14 | 0.0 | -1.6818 | 0.0 | 21.0 | 1.0 | 0.6 | 27.5 | 26.3±0.1 |
| 15~20 | 0.0 | 0.0 | 0.0 | 21.0 | 4.5 | 0.6 | 30.6 | 30.6±0.1 |