Sdt 2960 thermal analyzer

Calorimetric measurements were carried out using a Q2000 differential scanning calorimeter (DSC, TA Instruments, New Castle, DE, USA). Thermal analysis was carried out at a scanning rate of 20 °C/min. Samples (~3 mg) were heated to 200 °C and maintained for 5 min to erase previous thermal history before being cooled to −40 °C at a cooling rate of 20 °C/min. Samples were then reheated to 200 °C at a scanning rate of 20 °C/min (2nd heating) under nitrogen atmosphere using a nitrogen flow rate of 40 mL/min. Percentage crystallinity (X_c) of the synthesized polymer samples was determined using the following Equation (1): ${\mathrm{X}}_{\mathrm{c}}=\frac{∆{\mathrm{H}}_{\mathrm{m}}}{\mathrm{w}∆{\mathrm{H}}_{\mathrm{m}}^0}$
where $∆{\mathrm{H}}_{\mathrm{m}}$ is the melting enthalpy (J/g) of sample, w is the weight fraction of PHB in PU, and $∆{\mathrm{H}}_{\mathrm{m}}^0$ is the melting enthalpy of 100% crystalline PHB (146 J/g) [13 (link)].
Thermal degradation studies were carried out using TA Instruments D-TGA, SDT 2960 thermal analyzer. Experiments were conducted in air atmosphere at heating scans from 30 to 600 °C under dynamic heating rate of 10 °C/min (sample amount: 3–5 mg).

Elemental analyses (C, H, N) were performed on a Leco CHNS-932 microanalyzer. IR spectra were acquired on diluted KBr pellets in a ThermoNicolet IR 200 spectrometer in the 4000–400 cm⁻¹ spectral region. Thermal analyses (TG/DTA) were performed on a TA Instruments SDT 2960 thermal analyzer in a synthetic air atmosphere (79% N₂/21% O₂) with a heating rate of 5 °C·min⁻¹.

Elemental analyses (C, H, N) were carried out on a Euro EA Elemental Analyser. The content of zinc in the samples was estimated by means of ICP-AES measurements with a Horiba Yobin Yvon Activa spectrometer. An IR spectrum was collected on an FTIR 8400S Shimadzu spectrometer in the 4000–400 cm⁻¹ spectral region using KBr pellets. Thermal analyses (TG/DTA) were performed on a TA Instruments SDT 2960 thermal analyzer under a synthetic air atmosphere (79% N₂, 21% O₂) with a heating rate of 5 °C/min.