Isothermal microcalorimetry as a tool for studying oxidation stability of insulating liquids

The application of an isothermal microcalorimeter for the investigation of the oxidation stability of insulating liquids has been studied. We propose that the total integral heat signal (area below the calorimeter curves) is a good indicator of the degree of oxidation taking place in the sample during the experiment. Known and unknown insulating liquids have been used in this study, and the amount of available oxygen in the samples has been varied. The results show that isothermal microcalorimetry is well suited for characterizing the oxidation stability of insulating liquids.