Analysis of 9 commonly used materials for rubber seals

The application of universal rubber seal products in national defense, chemical, coal, petroleum, metallurgy, transportation, and machinery manufacturing industries is becoming increasingly widespread, and has become a basic component and accessory in various industries. So what are the commonly used materials for rubber seal products?

Analysis of 9 commonly used materials for rubber seals

1. Nitrile rubber

Nitrile rubber has excellent resistance to fuel oil and aromatic solvents, but is not resistant to media such as ketones, esters, and hydrogen chloride. Therefore, nitrile rubber is mainly used in oil resistant sealing products.

2. Chloroprene rubber

Chloroprene rubber has good oil and solvent resistance properties. It has good resistance to gear oil and transformer oil, but is not resistant to aromatic oils. Chloroprene rubber also has excellent resistance to weather aging and ozone aging. The crosslinking fracture temperature of chloroprene rubber is above 200 ℃, and chloroprene rubber is usually used to make door and window sealing strips. Chloroprene rubber also has good corrosion resistance to inorganic acids. In addition, due to its good flexibility and impermeability, chloroprene rubber can be used to make film sheets and vacuum sealing products.

3. Natural rubber

Compared with most synthetic rubbers, natural rubber has good comprehensive mechanical properties, cold resistance, high resilience, and wear resistance. Natural rubber is not resistant to mineral oil, but is more stable in vegetable oils and alcohols. In the hydraulic brake system composed of a mixture of n-butanol and refined castor oil, the rubber bowl and rubber ring used as the sealing element are made of natural rubber, and natural rubber is commonly used as the sealing agent.

4. Fluororubber

Fluororubber has outstanding heat resistance (200-250 ℃) and oil resistance, and can be used to manufacture cylinder liner seals, rubber bowls, and rotating lip seals, significantly improving their service life.

5. Silicone rubber

Silicone rubber has outstanding resistance to high and low temperatures, ozone, and weather aging. It can maintain its unique elasticity, ozone resistance, weather resistance, and other advantages within the working temperature range of -70 to 260 ℃. It is suitable for making sealing gaskets required in thermal mechanisms, such as strong light source lampshade sealing gaskets, valve gaskets, etc. Due to the lack of oil resistance, low mechanical strength, and high price of silicone rubber, it is not suitable for producing oil resistant sealing products.

6. EPDM rubber

The main chain of EPDM rubber is a fully saturated straight chain structure without double bonds, and there are dienes on its side chains, which can be vulcanized with sulfur. EPDM rubber has excellent aging resistance, ozone resistance, weather resistance, heat resistance (can be used for a long time in an environment of 120 ℃), chemical resistance (such as alcohols, acids, strong bases, oxidants), but is not resistant to corrosion by aliphatic and aromatic solvents. EPDM rubber has the lowest density among rubbers and high filling properties, but lacks self adhesiveness and mutual adhesiveness. In addition, EPDM rubber has outstanding steam resistance and can be used to produce sealing products such as steam resistant membranes. EPDM rubber has been widely used in the production of accessories for washing machines, televisions, door and window sealing products, or various composite profiles of rubber strips.

7. Polyurethane rubber

Polyurethane rubber has excellent abrasion resistance and good impermeability, and is generally used within a temperature range of -20 to 80 ℃. In addition, it also has moderate resistance to oil, oxygen, and ozone aging, but is not resistant to acid, alkali, water, steam, and ketones. Suitable for manufacturing various rubber sealing products, such as oil seals, O-rings, and diaphragms.

8. Chloroether rubber

Chloroether rubber combines the advantages of nitrile rubber, chloroprene rubber, and acrylic rubber. It has good oil resistance, heat resistance, ozone resistance, flame resistance, alkali resistance, water resistance, and organic solvent resistance, as well as good processability. However, its cold resistance is poor. Chloroether rubber is still a good material for manufacturing sealing products such as oil seals, various sealing rings, gaskets, diaphragms, and dust covers even when the temperature is not too low.

9. Acrylic rubber

Acrylic rubber has heat-resistant oil properties (mineral oil, lubricating oil, and fuel oil), especially oil stability at high temperatures, generally up to 175 ℃, and can withstand temperatures of 200 ℃ during intermittent use or short periods of time. Its disadvantage is poor cold resistance. Therefore, in non cold regions, it is suitable to make oil seals that are resistant to high temperature oil, but not suitable for sealing products that are subjected to tensile or compressive stress at high temperatures.