A)Oxygen: Oxygen occurs in therubber with a free-radical chain reaction with the rubber molecules, themolecular chains are broken or cross-linked, causing changes in rubberproperties. Oxidation is one of the important reasons for rubber aging.
B)Ozone: Oxygen is a much morereactive and destructive chemical oxygen species that destroys molecularchains. However, the effect of ozone on rubber varies depending on whetherrubber is deformed or not. When acting on the deformed rubber (mainlyunsaturated rubber), a crack that is in a direction perpendicular to thedirection of the stress occurs, that is, the so-called "ozone crack".When acting on the deformed rubber, only an oxide film is formed on the surfacewithout cracking.
C)Heat: Raising the temperaturecan cause thermal cracking or thermal crosslinking of the rubber. But the basicrole of heat or activation. Improve the rate of oxygen diffusion and activationof oxidation reactions, thereby accelerating the rate of rubber oxidationreaction, which is a common phenomenon of aging
D)Light: The shorter the light,the greater the energy. Destructive effect on the rubber is the higher energyUV. In addition to ultraviolet light can directly cause the fracture of therubber molecular chain and crosslinking, the rubber due to the absorption oflight energy and generate free radicals, trigger and accelerate the oxidationchain reaction process. The outside light plays a role in heating. Light Anotherfeature of its director (with different heat) is that it is mainly in therubber surface into the students. High gel content of the sample, there will bemesh cracks on both sides, the so-called "light outer split