Fatigue ozone effects

In an atmosphere containing ozone, stretched samples of unsaturated elastomers develop surface cracks that grow in length and depth until they eventually sever the test piece. Even when they are quite small, they can cause a serious reduction in strength and fatigue life. Quite small concentrations of ozone will induce cracking, given sufficient time. The effect is so sensitive, in fact, that it is the basis for an ozone detection system (Mott and Roland, 1999). 

Antioxidants/ antiozonants 0-7 Inhibit attack by oxygen and ozone. Improve flex fatigue and inhibit the degradation effects of metal impurities... 

Ralox TMQ is a highly effective agent that prevents heat-induced aging and also provides minor protection against ozone and fatigue crack failure. Its major field of application is with black elastomers based on SBR, NR, IR, BR and NBR, as well as latices. A highly effective agent, Ralox TMQ is also added to polyethylene that has been cross-linked with peroxide. 

Synergistic degradation effects can also lead to early joint failure. Fatigue causes faster crack growth than do steady-state stresses. Mechanical stress in combination with environmental stresses like standing water, heat, ultraviolet light, acid rain, ozone or solvents can reduce service life many fold. 

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