Table I.
Formulations and Process Parameters Applied During HME
| Formulation | Matrix material | Active ingredient (wt%) | Process parameters | Knife rotational speed (rpm) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Torque (%) | Barrel zone temperatures (°C) | |||||||||||||
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | |||||
| 1 | Cornstarch | Without (20% H2O) | 18 | 65 | 85 | 85 | 85 | 85 | 85 | 85 | 85 | 85 | 85 | 1300 |
| 2 | Cornstarch | Antipyrine 20% (aqueous solution) | 7 | 65 | 85 | 85 | 85 | 85 | 85 | 85 | 85 | 85 | 85 | 1500 |
| 3 | Cornstarch | Codeine phosphate 10% (aqueous solution) | 22 | 65 | 85 | 85 | 85 | 85 | 85 | 88 | 88 | 88 | 87 | 1500 |
| 4a | Cornstarch | Codeine phosphate 20% (aqueous solution) | – | – | – | – | – | – | – | – | – | – | – | – |
| 5 | Xanthan | Without (20% H2O) | 16 | 70 | 85 | 85 | 85 | 85 | 85 | 85 | 85 | 85 | 85 | 1600 |
| 6 | Xanthan | Antipyrine 20% (aqueous solution) | 2 | 50 | 50 | 63 | 85 | 85 | 85 | 85 | 85 | 85 | 83 | 2000 |
| 7 | Gum arabic | Without (20% H2O) | 25 | 60 | 65 | 75 | 75 | 75 | 75 | 75 | 75 | 74 | 74 | 1600 |
| 8 | Gum arabic | Antipyrine 20% (aqueous solution) | 11 | 60 | 60 | 65 | 65 | 65 | 65 | 65 | 65 | 60 | 65 | 1600 |
aAdding 20% codeine phosphate resulted in highly viscous strands that were not suitable for hot die face pelletizing