To describe and interpret a typical TGA measurement.
Uncured KU600 epoxy resin powder.
Measuring cell: TGA/SDTA
Pan: Alumina 30 μL, without lid
Sample preparation: The crucible was filled with 15.931 mg loose powder, i.e. without compacting.
TGA measurement: Heating from 30 to 700 °C at 10 K/min
Atmosphere: Purge gas, 50 mL/min: first nitrogen, then switched automatically to air at 600 °C, as well as 20 mL/min nitrogen as protective.
The TGA curve shows two large mass loss steps: first the decomposition of the polymer through pyrolysis between 320 and 480 °C, and second, after switching to air at 600 °C, the combustion of the carbon that had been mainly produced during pyrolysis. The slight loss of moisture up to 100 °C is hardly noticeable. The two main steps can also be seen as large DTG peaks
The content of polymer and filler can be directly estimated from the percent display of the TGA curve.
The TGA, DTG, and SDTA® curves show the pyrolysis and combustion processes exhibited by thermosets when they are heated in an inert gas atmosphere (pyrolysis) or air (combustion with oxygen). Effects that do not result in a change in mass, can only be observed in the SDTA ® curve.
Mass Changes on Heating a Thermoset | Thermal Analysis Handbook No.HB15 | Application published in METTLER TOLEDO TA Application Handbook Thermosets, Volume 1