Oxidation induction time

The Oxidation Induction Time (OIT) and Temperature (OOT) are measured in a Differential Scanning Calorimeter (DSC).

This simple standard test method characterizes the oxidation stability of oils, fats, fuels or polymers. The information is important because external influences such as light, chemical or biological substances as well as radiation and temperature can greatly alter the physical properties of a material.

There are two standard OIT methods: On the one hand, the dynamic procedure, in which the sample is heated steadily in an oxygen-containing atmosphere and the oxidation can be observed as a change in the course of the curve. For this purpose, both the temperature and the duration are measured from the beginning of the oxidation.

On the other hand, there is the static method of heating the sample in a protective atmosphere, typically nitrogen, to 190-220° C. After reaching a constant temperature, oxygen or air is introduced into the chamber. Subsequently, the duration between oxygen / air inlet and the beginning of the oxidation (exothermic effect) is measured.