Determination of the Moisture Content of PA66 by TGA and DSC

Sample

Ultramid C3ZM6 (pellet), Bergamid A70B30 (molded part) and Ultramid A3K (molded part)

Conditions

Measuring cells: DSC821^e with sample changer, TGA850

Pan: Aluminum standard 40 μl , pierced lid

         Alumina 70 μl for TGA

Sample preparation: Disks were cut and soaked for several hours in water prior to measurement

DSC measurement: Heating from 30 to 300 °C at 10 K/min, quench-cooling to room temperature in the sample changer, followed by a second heating run to 30 to 300 C at 10 K/min

TGA measurement: Heating from 30 to 400 °C at 10 K/min

Atmosphere: Nitrogen, 50 cm³/min

Interpretation

The measurements show that the absorbed moisture evaporates relatively slowly from the approx. 1-mm thick sample. The TGA weight loss step and the endothermic DSC peak are correspondingly broad. The increasing mass loss above 300 °C is due to the onset degradation of the polyamide.

Conclusions

Both TGA and DSC can be used to determine the moisture content. The detection limit with both techniques is about 0.1%

The recrystallization peak indicates that crystallization is incomplete. 

_{Determination of the Moisture Content of PA66 by TGA and DSC | Thermal Analysis Handbook No.HB229 | Application published in METTLER TOLEDO TA Application Handbook Thermoplastics}