Magnesium oxide, with its high purity, high activity and good dispersibility, is widely used in the rubber industry as a reinforcing agent, acidity regulator, accelerator and flame retardant, which greatly enriches the types and application fields of rubber products.
1. Application in natural rubber (NR)
Natural rubber, with its excellent elasticity, sealing and insulation, occupies an important position in the fields of tires, hoses, tapes, etc. However, natural rubber is easily affected by heat and oxygen aging during processing, resulting in performance degradation. At this time, magnesium oxide is introduced as an important auxiliary agent. By absorbing the acidic substances produced during the rubber processing, the pH value of the rubber is adjusted to prevent rubber aging, and it can also be used as a filler to improve the hardness and wear resistance of the rubber.
2. Application in styrene-butadiene rubber (SBR)
Styrene-butadiene rubber is one of the most produced and widely used synthetic rubbers in the world, and is widely used in tires, shoes, hoses, tapes and other fields. In the processing of styrene-butadiene rubber, magnesium oxide is mainly used as a vulcanization accelerator. It can work synergistically with other components in the vulcanization system to accelerate the vulcanization reaction, improve the vulcanization efficiency, and enable rubber products to achieve the best physical and mechanical properties. In addition, magnesium oxide can also enhance the adhesion between rubber and skeleton materials, and improve the durability and safety of products. Especially in the production of high-performance tires, adding an appropriate amount of magnesium oxide can effectively improve the tire’s resistance to flex cracking and aging, and extend its service life.
3. Application in chloroprene rubber (CR)
Chloroprene rubber is known for its excellent oil resistance, solvent resistance, weather resistance and flame resistance. It is widely used in wires and cables, hoses, conveyor belts and other fields that require special properties. In the formula of chloroprene rubber, magnesium oxide, as an acidity acceptor and cross-linking aid, can effectively neutralize the hydrogen chloride generated during the rubber processing process to prevent its damage to the rubber molecules, while promoting the cross-linking reaction of the rubber and improving the cross-linking density and physical properties of the vulcanized rubber. In addition, magnesium oxide can also improve the processing performance of chloroprene rubber, reduce the viscosity of the rubber, improve fluidity, and facilitate molding processing.
4. Application in EPDM
EPDM is widely used in automotive parts, building sealing materials, wire and cable sheathing and other fields due to its excellent heat resistance, ozone resistance, aging resistance and chemical resistance. In the formulation design of EPDM rubber, magnesium oxide, as an inorganic filler and flame retardant, can significantly improve the rigidity and hardness of rubber, while giving rubber products good flame retardant properties. In addition, magnesium oxide can also synergize with other additives in rubber such as carbon black and diatomaceous earth to further improve the comprehensive performance of rubber. Especially in the production of automotive sealing strips, the addition of magnesium oxide can significantly improve the high temperature resistance and sealing effect of the sealing strips and extend the service life.
5. Application in silicone rubber (SiR)
Silicone rubber is widely used in medical, food, electronic and electrical fields due to its unique characteristics of high temperature resistance, cold resistance, aging resistance and physiological inertness. In the processing of silicone rubber, although magnesium oxide is not as commonly used as in other rubbers, it still plays an important role in certain specific applications. For example, in situations where the flame retardancy of silicone rubber needs to be improved, magnesium oxide can be used in combination with other flame retardants to form a synergistic flame retardant effect, significantly improving the flame retardancy level of silicone rubber. At the same time, magnesium oxide can also improve the processing performance of silicone rubber, reduce the viscosity of the rubber, and improve production efficiency.
6. Application in butyl rubber
Butyl rubber is widely used in tires, seals, and seismic isolation materials due to its excellent air tightness, aging resistance, and heat resistance. Active magnesium oxide, as a vulcanization accelerator and reinforcing agent for butyl rubber, not only improves the vulcanization speed and degree of vulcanization of rubber, but also significantly enhances the physical properties and heat resistance of rubber.
7. Application in fluororubber
Fluororubber has excellent oil resistance, solvent resistance, and high temperature resistance. In the production process of fluororubber, active magnesium oxide acts as a catalyst and hydrogen fluoride acceptor to promote the vulcanization reaction and improve the scorch performance. At the same time, magnesium oxide also improves the thermal stability of vulcanized rubber and extends the service life of rubber products in high temperature environments.
In summary, magnesium oxide, as an important additive in the rubber industry, not only improves the physical and mechanical properties of rubber products, but also broadens the application fields of rubber materials through organic combination with different types of rubber.