The water content was predictable

A customer called us as they had problems interpreting the results from Karl Fischer experiments with a certain product: Large variations were observed between measurements performed on different days, showing water content between 1 and 4%. We suggested a TGA measurement (where the sample is heated under controlled conditions) and a DVS measurement (where the extent of water binding as a function of temperature is examined).

These results showed that the product was able to take up around 8% of water at room temperature (=quite hygroscopic), and the uptake was highly dependent on the relative humidity and temperature. Thus, the large variations they observed in their results were caused by differences in the starting conditions of the experiment.

 

vandhane