| Factors | Tag | Symbol | Units | Levels | ||||
|
| −α | −1 | 0 | 1 | +α | |||
| Foaming time | t | X1 | min | 5 | 7.03 | 10 | 12.97 | 15 |
| Mold opening temperature | T | X2 | ˚C | 80 | 88.1 | 100 | 111.9 | 120 |
| ADA blowing agent weight concentration | IC | X3 | Wt% | 4.20 | 4.91 | 5.95 | 6.99 | 7.70 |