2.4. Differential Scanning Calorimetry (DSC) Measurements

Differential scanning calorimetry (DSC) tests, to evaluate the characteristic temperatures and the corresponding phase change enthalpies, were carried out on a DSC Q-20 instrument (TA Instruments, New Castle, De, USA) in a nitrogen atmosphere at a heating rate of 10 °C/min, equipped with a liquid sub-ambient accessory and calibrated with high purity standards. Polymer films were cut into small pieces of about 2 mm² and 10–12 mg in weight and placed in a 50 μL sealed aluminum pan. After an isotherm of 5 min at 20 °C, samples were heated with a scanning rate of 10 °C/min, from 20 to 180 °C (first scan) and then, after a further isotherm of 2 min at 180 °C, were cooled to 20 °C at a rate of 10 °C/min. Finally, after an isotherm of 3 min, samples were reheated from −20 °C/min to 180 °C/min at 10 °C/min (second scan). All the experiments were performed under nitrogen flow (20 cm³/min). The melting temperature (T_m) was determined as the peak value of the endothermic phenomena in the DSC curve. The melting enthalpy (∆Hm) of the crystal phase was calculated from the area of the DSC endothermic peak. T_m and ∆H_m values were collected from the first scan. The average error in thermal effect measurements was approximately ±3%.