Dust ring manufacturers tell the performance of silicone sealing ring

Performance of silicone seal ring

The silicone rubber seal ring has excellent heat resistance, low temperature elasticity, excellent oxidation resistance and ozone resistance. Silicone rubber seals are highly breathable and selective. Good electrical insulation properties (volume resistance greater than 10. Ω). Cm, breakdown field strength exceeds 30KV/mm), corona resistance, arc resistance. But adding conductive carbon black, nickel powder, aluminum powder, silver powder (volume resistance up to 5-0.02. Ω) can obtain moderate conductivity. cm). The surface of the silicon seal ring can be low water absorption and can be used as an isolation material.

Waterproof, but poor water vapor resistance, pressure higher than 50psi is not recommended. Suitable for most oils, chemicals and solvents. Generally speaking, silicone rubber has good acid and alkali resistance, and has good resistance to polar solvents, but it has no resistance to alkane hydrogen and aromatic oil. Not recommended for most concentrated solvents, petroleum products, concentrated acids and dilute aqueous caustic soda. The special silicone rubber also has the characteristics of radiation resistance, fire resistance and oil resistance. Silicone rubber sealing ring has low compressive strength and poor wear resistance, and is generally not used for dynamic sealing.

The polymer molecule of the silicone seal ring is a chain structure composed of silicon oxygen bonds, and its main component is high molar linear polysiloxane. Since the Si-O-Si bond is a basic bond, the silicon atom is mainly bonded to the hydroxyl group, and a small amount of unsaturated group is introduced in the side chain. The intermolecular force is small, and the molecule is a helical structure. The hydroxyl groups are arranged on the outside and can rotate freely, so that the silicone rubber sealing ring has better heat resistance, insulation and chemical properties than other ordinary rubbers. Typical silicone seals are polydimethoxymethylene

Siloxane has a spiral molecular formula, small intermolecular force, good toughness. At the same time, the formaldehyde free radicals outside the screw can rotate freely. As a result, silicone seal rings have unique surface properties such as hydrophobicity and surface resistance

The main component of the silicone seal ring is silicone. The main molecular chain of silica gel is replaced by silicon atoms and oxygen atoms. It is a polymer elastic material, both inorganic and organic properties. At present, hydroxyl vinyl silicone rubber is widely used, consisting of dimethyl siloxane and a small amount of vinyl siloxane.