The influence of temperature and the kind of the atmosphere on polystyrene thermal degradation

Abstract

The influences of atmosphere and sample heating rate on the degradation temperature were estimated. Thermal degradation of polystyrene (PS) was carried out in a flow tubular furnace under isothermal conditions and in a thermogravimetric analyser under dynamic conditions. The experiments were performed in both a nitrogen and an air atmosphere. The thermal behaviour of tested polymer was determined on the basis of the thermogravimetric curves. The process of polystyrene thermal degradation in the tubular furnace was studied at the temperatures of 300°C, 400°C, 500°C, and 600°C for 30 min. The volatile and less-volatile thermal degradation products were analyzed using gas chromatography - mass spectrometry (GC-MS) and Fourier transform infrared spectroscopy (FT-IR) methods. 64 degradation products were identified. Main of them were styrene and its dimer and trimer. In air atmosphere, the concentration of low molecular weight degradation products increases with the temperature while in nitrogen the maximal concentrations of some of them are reached at temp. 500°C.