For the selection of anti-aging agent, due to the different types of rubber and vulcanization mode can choose different anti-aging agent, the following is a variety of rubber in the routine use of anti-aging agent introduced one by one.
1. NR, SBR for the aging agent!
The selection of anti-aging agent should be considered from the aspects of improving the heat resistance, ozone resistance and flexibility of rubber.There is a greater demand for anti-aging agents with good persistence and stability.
2. Used as an anti-aging agent in NBR
For NBR, the effect of anti-ozone cracking aging agent is small.This is because the antioxidant is well soluble in NBR, making it difficult to migrate to the rubber surface.Ozone resistance can be achieved if used with paraffin.For NBR, the paraffin with low molecular weight works better.
3. Anti-aging agents used in CR
Compared with NR and SBR, CR has very good ozone resistance. However, ozone cracking may occur in long-term use.In CR, a small amount of 810-na (IPPD), 6C, DP and other anti-ozone cracking aging agents can significantly improve the ozone resistance.Also, as a continuous heat-resistant and anti-aging agent, CD(carbon diimine) is effective.
4. Anti-aging agent used in ECO
Chloro-ether rubber (ECO) is prone to softening and aging, and anti-aging agents that can effectively inhibit softening and aging include NBC(nickel dibutyl dithiocarbamate), MB(mercapto benzimidazole), 224(TMDQ).In chloroether rubber, if excessive with amine antiaging agent, the ozone resistance will be reduced.
5. Anti-aging agent used in ACM(acrylate rubber)
Acrylate rubber aging has both hardening aging and softening aging.Therefore, it is necessary to choose suitable anti - aging agent.For hardened and aging acrylate rubber, it is more effective to choose anti-aging agent CD, while for softening and aging acrylate rubber, it can choose 224 and 6C anti-aging agents.
6. Anti-aging agent used in peroxide vulcanized EPDM rubber
Peroxide vulcanized rubber for aging, imidazole MB, MBZ(sulfhydrazole zinc salt) in general, in addition, in the amine of aging, but also choose to use less impact on the cross-linking of 224, CD aging.In EPDM, MB and 224 or CD can be used together, so that the adhesive has excellent heat resistance.They are not used because they are not effective in sulfurated rubber.