Difference between Silicone Rubber and PTFE sealing

- Aug 26, 2019-

Silicone rubber and PTFE are used as sealings gaskets on conveying equipment.What is difference between silicone rubber and PTFE?


First, they have different features :

Silicone rubber has some extension tension,flexibility , excellent insulation, pressure resistance, high temperature resistance, low temperature resistance, chemical stability, environmental protection and safety, no odor, food grade .silicone rubber is non-toxic and tasteless, which can not be insoluble in water and any solvent.Thus,silicone rubber is a green product.

For  the characteristics of PTFE gasket: it is acid and alkali resistance, it can endure high temperature resistance and resistance to various organic solvents.

Second, they have different applications:

(1)Silicone gasket is widely used in conveying equipment which are designed to transport materials ,such as  plexiglass, glass crafts, display stands, household appliances, furniture products, hardware accessories, transparent plastic products,etc.

(2) For PTFE gasket which has a wide range of applications in screw conveyors that are used in the petroleum, chemical, pharmaceutical, electric power, and steel industries. PTFE gasket also is a suitable media, including almost all chemical components ,such as water, oil, acid solution, and alkali solution.

Third, they have different roles.

(1)silicone gasket is with beautiful appearance, and has the functions of shockproof, anti-skid, anti-collision and anti-scratch, and has high transparency.

(2)PTFE gasket is with good mechanical toughness; even if the temperature drops to -196 ° C, can maintain 5% elongation. It is inert to most chemicals and solvents, resistant to strong acids and bases, aqua regia and various organic solvents.If screw conveyor is transported milk powder or sauces, there need PTFE with FDA certifications. While silicone rubber gasket do not have FDA certificates.