The reason on silica gel aging

1, the role of heat, increasing the temperature can cause thermal cracking or thermal crosslinking silicone rubber products. But basic function of thermal activation. Improve thediffusion rate of oxygen activation and oxidation reaction, thus speeding up the rubber oxidation reaction speed, which is a kind of aging phenomenon -- hot oxygen aging.

2, the role of oxygen, oxygen free radical chain reaction in rubber with rubber molecules, the molecular chain rupture or excessive crosslinking, properties of silicone rubber products caused by the change of. Oxidation is one of the important reasons for the aging of rubber.

3, light, light energy, the greater the shorter. Damage to the rubber from the high energyultraviolet. In addition to the direct cause of fracture and UV crosslinked rubber chain, rubberdue to absorb light energy and produce free radicals, trigger and accelerate the oxidationprocess of chain reaction. Heating part by outside light. Light the other characteristics (long and thermal effects) is mainly in the rubber surface into students. The gum content of high sample,both sides will appear net cracks, the so-called "light outer crack".

4, the effect of ozone, the chemical activity of oxygen ozone is much higher, more destructive, it is also the molecular chain was broken, but the effect of ozone on the rubber with rubberdeformation and not different. As for the deformation of the rubber (mainly unsaturated rubber),crack and stress direction, the so-called "ozone cracking"; effect on the deformation of the rubber, only surface oxide film without cracking.

5, the role of water, the moisture content has two aspects: silicone rubber products in the humid air or rain soaked in water, easy to damage, this is because the rubber in water soluble substances and water components by water extraction group Tsuen dissolved. Hydrolysis or absorption and other causes. Especially in the effect of alternative water immersion and atmospheric exposure, will accelerate the destruction of rubber. But water is not destructive torubber in certain circumstances, even delay the aging effect.

6, the effect of mechanical stress, the mechanical stress under the repeated action, will make the rubber chain fracture generated free Tsuen, causing oxidative chain reaction, the formation of chemical process. The mechanical fracture of the molecular chain and mechanical activationoxidation process. How can a dominant, depending on the terms and conditions. In addition,under stress due to ozone cracking.

7, there are other reasons for the chemical medium, valence metal ion, high-energy radiation,electrical and biological etc..