Mettler-Toledo TG-DSC I/1600 HT simultaneous thermal analyzer, coupled with Thermofisher Nicolet 6700 FTIR using a Teflon tube, was used to study the pyrolysis behavior. The experiments were done on the thermo-balance at a linear heating rate of
5 ◦C/min within the temperature range from the room temperature (30 ◦C) to 1200 ◦C, at a steady air flow. A description of the instrumentation and principles of the experiment have been published elsewhere [25,31,32]. The spectrum scope was located in the range of 400–4000 cm−1 and the resolution factor was selected to be 1 cm−1. In order to reduce the influence of sample amount on the intensity of infrared absorption, the mass for the sample was set at (25±0.05) mg.