*3.3. Analysis*

The 1H-NMR spectra were measured on a Bruker AV II-400 MHz spectrometer (USA) using DMSO-d6 as a solvent at 25 ◦C. The FTIR spectra were recorded on a Nicolet is 50 FTIR spectrometer within the 4000–400 cm<sup>−</sup><sup>1</sup> region with KBr matrix.

The morphology of the fractured surfaces of specimens was observed with a ZEISS Sigma 300 FESEM (Schnelldorf, Germany) with an accelerating voltage of 10 kV.

TGA and DTG analyses were carried out with a PerkinElmer TGA 4000 thermogravimetric analyzer (Waltham, MA, USA) at a heating rate of 10 ◦C/min from 30 to 650 ◦C under a nitrogen atmosphere.

LOI values were recorded on a Jiangning JF-3 oxygen index analyser (Nanjing, China) with sample dimensions of 130 mm × 6.5 mm × 3 mm according to ASTMD 2863-97. UL-94 vertical burning tests were performed using a Jiangning CZF-3 horizontal and vertical combustion tester (Najing, China) with sample dimensions of 130 mm × 13 mm × 3.0 mm in accordance with ASTMD 3801-2010.

CONE tests were carried out with a FTT cone calorimeter (East Grinstead, England) under an external heat flux of 50 kW/m2. Sample dimensions were 100 mm × 100 mm × 3 mm according to ISO 5660.

Tensile properties were determined using a CMT4202 universal testing machine (Shenzhen, China) according to ASTM D638, at a test speed of 10 mm/min. Specimens were dumbbell-shaped with dimensions of 75 mm × 4 mm ×1 mm.
