Ozone Resistance
Posted on 31/12/2018 Category:
The ability of rubber to withstand exposure to ozone without cracking or breaking. Ozone can be naturally present, or produced by adjacent processes. Test pieces are usually placed under a small degree of tension e.g. by bending round a mandrel or stretching by 5%. The sample is exposed under static conditions to a controlled atmosphere containing ozone (typically 50 pphm). The cracks are graded by standard photographs, by measurement or by description, e.g. ‘visible under 10 x magnification’ ‘visible to the unaided eye’ etc. Results may be recorded as the time taken to reach a particular grade of cracking, or by the grade of cracking apparent after a fixed period of time.
