Nitrile butoxide (NBR) has relatively good aging resistance, mainly due to its chemical structure and the antioxidant that can be added. The following is a detailed analysis of the aging resistance of nitrile rubber:
First, overview of aging resistance
During the aging process, the properties of nitrile rubber will gradually change. However, compared with some other rubber materials, NBR has better aging resistance. This is mainly reflected in its ability to resist thermal oxygen aging, ozone aging and light aging.
2. Factors affecting aging resistance
Acrylonitrile content: The content of acrylonitrile has a certain effect on the aging resistance of nitrile rubber. With the increase of acrylonitrile content, the heat resistance of nitrile rubber will increase, but the low temperature resistance will decrease. At the same time, the polarity of acrylonitrile increases the bonding strength of nitrile rubber.
Antioxidant addition: nitrile rubber without antioxidant performance is poor in terms of aging resistance. However, by adding antioxidant, the aging resistance and heat resistance of NBR can be significantly improved. These antioxidants can trap free radicals and inhibit oxidation reactions, thereby extending the service life of NBR.
Environmental factors: The aging resistance of NBR is also affected by environmental factors such as temperature, light, ozone and so on. The increase in temperature will accelerate the internal molecular movement of rubber, resulting in the breakdown and recombination of molecular chains, thus accelerating the aging process. Light and ozone will also have a destructive effect on nitrile rubber, resulting in surface cracking, oxidation and other phenomena.
3. Test method of aging resistance
For the aging resistance test of nitrile butadiene rubber, the commonly used methods include thermal oxygen aging test, ultraviolet aging test and ozone aging test. These test methods can simulate the aging process of NBR in the actual use environment, so as to evaluate its aging resistance.
4. Application examples
Nitrile butadiene rubber is widely used in many fields because of its good aging resistance. For example, in the petrochemical industry, nitrile butadiene rubber is used to manufacture components such as seals and gaskets to resist the erosion of high temperature, high pressure and corrosive media. In the power industry, nitrile butadiene rubber is used to manufacture components such as cable sheaths and insulation materials to ensure the normal operation of power equipment.
Nitrile butadiene rubber has relatively good aging resistance. However, in practical applications, it is also necessary to select the appropriate nitrile rubber material according to the specific use environment and requirements, and add an appropriate amount of antioxidant to improve its aging resistance.