Dsc 8500

The thermal properties were determined using a differential scanning calorimeter DSC 8500 (Perkin Elmer, Waltham, MA, USA). The tests were carried out at a heating rate of 10 °C/min under a constant flow of nitrogen between 30 °C up to 200 °C. The samples were heated at the beginning of the test from 30 °C to 200 °C to remove their prior thermal history, followed by cooling to room temperature. The heating cycle was repeated again to 200 °C.
The degree of crystallinity was calculated as per (Equation (1))
$Xc=\left(\Delta \mathrm{Hm}/\Delta °\mathrm{Hm}\right)*100$
where $Xc$ is the degree of crystallinity; $\Delta \mathrm{Hm}$ is the melting enthalpy of the polymer, and the reference value ( $\Delta °\mathrm{Hm}$ ) that was assumed in this study for 100% crystalline PE is 293 J/g [20 ].

DSC measurements were accomplished with a DSC 8500 from Perkin Elmer. Analyses were performed under N₂ atmosphere with a flow rate of 20 mL·min⁻¹. About 5 mg of the sample were heated in an aluminum pan from −20 °C to 200 °C (first heating cycle), then cooled again to −20 °C, and afterward heated once more to 200 °C (second heating cycle). The heating/cooling rate was set to 20 and 40 °C·min⁻¹, respectively. Glass transition temperatures (T_g), crystallization temperatures (T_c), melting points (T_m), and the associated enthalpies with crystallization and melting (ΔH_c and ΔH_m, respectively) were calculated from the second heating ramp. The percentage crystallinity was calculated from the cooling step after the second heating, using the following equation [25 (link)]: $$X [\%]=\frac{\Delta H_m}{\Delta H_m^0}\times 100,$$
where $\Delta H_m$ is the enthalpy of fusion in J/g of the experimental peak for each sample, and $\Delta H_m^0$ is the corresponding melting enthalpy of pure crystalline PHBV (146 J/g) [26 (link)].

The obtained compounds were analyzed on Perkin Elmer DSC8500 differential scanning calorimeter (Waltham, MA, USA). Heat flow was measured from −70 °C to 120 °C (upper limit set by anticipated sample decomposition temperature), with heating rate of 10 °C/min under dynamic nitrogen atmosphere with flow of 20 mL/min. The sample was prepared by weighing a small amount (2–5 mg) of compound in an aluminum pan, which was then closed with aluminum lid and crimped. Measured thermograms are presented in Supplementary Materials, Figures S22 and S23.

The glass transition temperature (T_g) of the photocross-linked polymers were estimated by differential scanning calorimetry (DSC). The measurements were performed on a DSC 8500 apparatus (Perkin Elmer, Llantrisant, UK) with a heating-cooling-heating rate of 10 °C·min⁻¹ under a nitrogen atmosphere (nitrogen flow rate 50 mL·min⁻¹). The T_g value was taken as the middle point in the heat capacity step of the glass transition.

Differential scanning calorimetry was recorded by a DSC apparatus (DSC 8500, PerkinElmer, Inc., Waltham, MA, USA) with a heating rate of 10 °C/min and temperature range of 26–120 °C. In each hermetic aluminum pan, a 5 mg gel sample was sealed, and an empty pan was used as reference.