Thermogravimetric analysis, or TGA, is a common technique allowing the characterization of physico-chemical parameters in the field of polymers and materials. The TGA results is a curve of the mass loss of a sample as a function of the temperature. This mass loss often generates evolved gases, or EGA, whose composition can be more or less complex.

When the mass loss is characterized by dehydration, the emission of simple light compounds such as hydrogen, carbon dioxide, etc., coupling with a Micro GC, an FTIR or an online MS is generally sufficient and has the advantage of a short analysis time (< 1 minute). You can see our application note on this topic for illustration.

When the evolved gases are of more complex composition with a large number of molecules, these analysis techniques have limitations. In this case, the alternative choice is coupling with a gas phase chromatograph coupled with a mass spectrometer (GC/MS).

Indeed, the coupling with a GC/MS makes it possible to provide detailed qualitative and quantitative information on all the molecules emitted. Mass spectrometry also allows the formal identification of the molecules detected, which proves to be a remarkable aid when the EGA is very complex or when the information on the sample studied is limited.

However, a GC/MS analysis is long, between 30 minutes and 1 hour! Much too long for a direct coupling with a TGA for the analysis of the evolved gases. The EGABOX developed by CHEMLYS makes it possible to sample up to 16 fractions of gas emitted during interesting mass loss times selected by the user. Thus, you are no longer limited by the analysis time of your GC/MS and you can obtain molecular information of your evolved gases over your entire TGA cycle.