Table 2.
Melting point temperature (Tm) and degree of crystallinity (XC) of the PP cups in the first and second DSC heating cycle.
| Heat treatment |
Tm (°C) |
XC (%) |
|||
|---|---|---|---|---|---|
| Temperature (°C) | Duration (min) | 1st heating | 2nd heating | 1st heating | 2nd heating |
| 40 | 10 | 146.6 | 145.8 | 31.3 | 34.4 |
| 30 | 145.3 | 144.9 | 31.5 | 35.7 | |
| 60 | 144.4 | 144.2 | 30.6 | 34.3 | |
| 120 | 145.2 | 145.6 | 29.6 | 34.0 | |
| 180 | 146.9 | 147.1 | 29.0 | 33.5 | |
| 1440 (1 day) | 144.7 | 144.7 | 28.0 | 34.2 | |
| 7200 (5 days) | 146.4 | 146.1 | 28.9 | 31.1 | |
| 90 | 10 | 144.9 | 146.4 | 29.8 | 32.9 |
| 30 | 146.4 | 147.5 | 29.6 | 32.8 | |
| 60 | 146.0 | 147.2 | 26.6 | 30.1 | |
| 120 | 145.0 | 146.2 | 32.0 | 34.9 | |
| 180 | 145.6 | 146.6 | 30.6 | 34.5 | |
| 1440 (1 day) | 145.2 | 146.4 | 29.4 | 31.5 | |
| 7200 (5 days) | 145.1 | 146.2 | 29.3 | 31.3 | |
| Non-preheated cups | Average (n = 5) | 145.1 | 145.8 | 31.5 | 34.5 |
| SD | 0.6 | 0.3 | 0.2 | 0.3 | |