Thermal and Thermo-Oxidative Degradation of Polystyrene with Ammonium Polyphosphate

The effect of ammonium polyphosphate (APP) on thermal and thermo-oxidative degradation of polystyrene (PS) was studied with methods of Thermogravimetry (TG), Gas Chromatography/Mass Spectrometry (GC/MS), Thermochromatography (ThGC), Size Exclusion Chromatography (SEC), and Fourier Transform Infrared Spectra (IR). APP slightly accelerated thermal degradation of PS in nitrogen due to its acidity. However, whether APP accel erated or retarded thermo-oxidative degradation of PS much depended on addi tion levels in air. At the low addition levels, APP seemed to retard thermal degradation of PS via formation of a glassy layer; at the high addition levels, APP seemed to accelerate thermal degradation of PS due to its acidity.