Ozone Test
Ozone resistance
Elastomers or Thermoplastic Elastomers - Resistance to Ozone Cracking - Static and Dynamic Testing
The test is for determining the resistance of vulcanized or thermoplastic elastomers against cracking under static or dynamic tensile strain in air with a defined concentration of ozone and at a defined temperature, excluding the influence of direct light.
The specimens are subjected to static or dynamic strain or alternating periods of dynamic and static strain in a closed chamber at a constant temperature of an atmosphere having a fixed constant ozone concentration. The specimens are periodically examined for cracks. Three different evaluation methods are described for the selected ozone concentrations and temperatures:
a) The occurrence or absence of cracks is determined after the test period at a specified static or dynamic elongation or a combination of static and dynamic elongation. If necessary, a description of the crack image is made;
b) The time to first occurrence of cracks is determined for all related strains (static or dynamic strain or a combination of static and dynamic strain);
c) The critical strain is determined for all test periods (applies only to tests with static tensile strain).
Standard: DIN ISO 1431-1 and ISO 7326
