Oxidation kinetics describes how the rate of oxidation changes with time under defined test conditions. Oxygen uptake can be one measure of this process, but it is not a direct measurement of a grommet's remaining service life.
Interpreting test results
Some rubber compounds show an initial period of relatively slow oxidation followed by a faster reaction. The shape of the curve depends on the polymer, additives, specimen dimensions and test conditions. It should not be assumed to follow the same stages for every compound.
A meaningful comparison requires the same temperature, oxygen exposure and measurement method. Report the units on both axes and identify the specimens. Changes in tensile properties, hardness or sealing performance should be assessed separately against the application requirements.
Applying the data
Use oxidation data alongside heat-aging and application tests when selecting a compound. A curve without a traceable test method or specimen description cannot substantiate a product lifetime or temperature rating.
