2.3. Differential scanning calorimetric (DSC) analysis
The DSC analyses were carried out on a CSC 4100 Multi-cell Differential Scanning Calorimeter (Calorimetry Sciences Corp., Utah, USA). Sup-samples of the samples used for NMR measurements (0.3–0.5 g) were placed into the DSC sample cells and placed in the DSC together with an empty reference cell. DSC scans were recorded from 3 to 90 C with a heating rate of 1 C/min.