DSC was conducted using a DSC Q2000 (TA Instruments, Newcastle, DE, USA). Samples of about 5 mg were prepared in sealed aluminium pans and heated from +5 °C to +200 °C and subsequently cooled to -50 °C at a linear rate of 10 °C min -1 in a nitrogen atmosphere. This cycle was repeated three times, with a final cooling to room temperature. The glass transition temperature (Tg) was obtained from the inflection point of the second heating cycle and the melt temperature (Tm) is the peak maximum of the endothermic curve in the first heating. For modulated DSC measurements the samples were equilibrated at +5 °C for 5 min followed by a temperature ramp from +5 °C to +200 °C with a modulated heating rate of 3 °C min -1 with a frequency of ±1 °C every 60 s. The data was evaluated using Origin software.