Rubber o-rings and other rubber products in the processing, storage and use process, due to the internal and external factors caused by a combination of physical and chemical properties and mechanical properties of rubber gradually deteriorate, loss of use value, this change is called rubber aging.
Show the crack on the surface, sticky, hardening and softening, pulverization, discoloration, long mildew, etc.
Causes of rubber aging are: oxygen, oxygen in the rubber with rubber molecules from the chain reaction, molecular chain rupture or excessive crosslinking, a change of rubber performance.
Oxidation is one of the important reasons for the aging rubber o-rings.
Hot: raise the temperature could lead to thermal cracking of rubber or thermal crosslinking.
But still hot the fundamental role of the activation.
Improve the oxygen diffusion velocity and activated oxidation reaction, so as to accelerate the oxidation reaction of rubber speed, this is the prevalence of an aging phenomenon -
The hot oxygen aging.
Moisture, moisture has two aspects: the effect of rubber in moist air in the rain, or soak in the water, and easy to damage, this is because the rubber composition such as clumps of water-soluble substances, tsuen wan, and water in the extraction dissolved by water.
Hydrolysis or absorption causes.
Especially in the soaking water and atmospheric exposure under the action of alternating, will accelerate the destruction of the rubber.
But in some cases the moisture on the rubber is not damage, even has the effect of delaying aging.
Mechanical stress: under the effect of mechanical stress again and again, can make the rubber chain fracture generates free tsuen, cause oxidation chain reaction, formation of chemical process.
Mechanical fault chain and mechanical activation oxidation process.
Which can dominate, depending on their conditions.
Other: the effect factors of rubber o-rings and chemical medium, intending to metal ion, high-energy radiation, electricity and biology etc.