Thermal decomposition characteristics of poly(phenylene sulfide) by stepwise Py-GC/MS and TG/MS techniques

The mechanism and kinetic model for thermal decomposition behavior of poly (phenylene sulfide) (PPS) was studied by stepwise pyrolysis/gas chromatography/mass spectrometry (stepwise Py-GC/MS) and thermogravimetry analysis/mass spectrometry (TG/ MS) techniques. The composition of evolved gases was determined by Py-GC/MS analysis. The mechanism and kinetic model of the pyrolytic behavior of PPS was investigated by TG/MS from room temperature to 900 degrees C. The mechanism indicated apparently one-stage pyrolysis, mainly by depolymerization, main chain random scission and carbonization. The initial scission of PPS was depolymerization and main chain random scission to evolve benzenethiol and hydrogen sulfide, respectively, as major products; while depolymerization dominated in lower temperature pyrolysis and main chain random scission dominated in higher temperature pyrolysis. The chain transfer of carbonization also produced in initial pyrolysis and gradually dominated at the higher pyrolysis temperature to form the high char yield of solid residue. Based on the analytical result, the kinetic model of pyrolysis was proposed and calculated. The calculated kinetics was compared with the experimental result, which was quite good consistence. (C) 2000 Elsevier Science Ltd. All rights reserved.