Figure 6. (a) DSC heating trace of i-PS melt-crystallized at 170°C for 300 min and heated at 10°C/min to 212°C. Sample then held isothermally for 60 min at 212°C and quenched back to 170°C (not shown). (b) Reheat of (a) at 10°/min. Scale is same as in Figure 1, Figure 2, and Figure 3. Initial bump in (b) is not sample related.

From

Experiment to Teach Multiple Melting Phenomena in Semicrystalline Polymers Using Differential Scanning Calorimetry

Kathy L. Singfield, Ashley J. Rowe

World Journal of Chemical Education. 2021, 9(3), 68-76 doi:10.12691/wjce-9-3-1