Evolved gas analysis from polystyrene in an oxygen atmosphere using a filament for low vacuum
MSTips No. 320
The thermogravimetry (TG)/differential thermal analysis (DTA)-mass spectrometry (MS) system can measure the weight change and heat input/output during sample heating with TG/DTA, and simultaneously measure the evolved gas with MS. In TG/DTA, it is possible to use not only inert gases such as helium and nitrogen, but also oxygen-containing auxiliary gases such as air to observe the thermal behavior of different atmospheric gases. Electron ionization (EI), which is widely used in MS, is an ionization method that utilizes thermal electrons from a filament. In an atmosphere with a large amount of oxygen, such as air, it is difficult to perform stable measurements over a long time because the filament wire tends to break due to thermal oxidation reactions.
JEOL has developed a filament for low-vacuum that utilizes a new wire with enhanced oxidation resistance to enable stable measurement by the EI method in an oxygen atmosphere.
In this study, the gases evolved from polystyrene at various oxygen concentrations were measured by TG/DTA-MS using a filament for low-vacuum.