Thermal Degradation of PBO Fiber Investigated by TGA-DTA/FTIR and Py-GC/MS

摘要

PBO fiber is so far the most high-temperature resistant polymer fiber, In this paper, the thermal degradation of PBO fiber under inert gas and air were studied using pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and thermogravimetric analysis coupled with Fourier transform infrared spectroscopy (TGA-DTA/FTIR). From room temperature to 1000°C, the residue rate of PBO fiber was 76.5% in nitrogen. The results of Py-GC/MS showed that the repeating unit of molecular chain was the most pyrolysis fragment, and CO2 and benzene also kept great yields in all pyrolysates. After 650 °C, the volatiles, including HCN, NH3, NO2, NO, CO, CO2, H2O and aromatic compositions can be found by TGA-DTA/FTIR in nitrogen. But in air, PBO almost lost mass all when the temperature reached 1000°C, Only several little molecular volatiles, such as CO2, NO2, HCN, H2O, etc were searched during degradation by the means of TGA-DTA/FTIR, especially after 650 °C, thermal degradation happened intensively and CO2 was produced importantly.