The silicone material and the viton material can work in temperatuer 200℃, if you need high temperatuer
Silicone O-Ring, the silicone or viton o rings are suggested. but there are difference between these two rubber material.
Silicones exhibit many useful characteristics, including:
Low thermal conductivity
Low chemical reactivity
Low toxicity
Thermal stability (constancy of properties over a wide temperature range of −100 to 250 °C).
The ability to repel water and form watertight seals.
Does not stick to many substrates, but adheres very well to others, e.g. glass.
Does not support microbiological growth.
Resistance to oxygen, ozone, and ultraviolet (UV) light. This property has led to widespread use of silicones in the construction industry (e.g. coatings, fire protection, glazing seals) and the automotive industry (external gaskets, external trim).
Electrical insulation properties. Because silicone can be formulated to be electrically insulative or conductive, it is suitable for a wide range of electrical applications.
High gas permeability: at room temperature (25 °C), the permeability of silicone rubber for such gases as oxygen is approximately 400 times[citation needed] that of butyl rubber, making silicone useful for medical applications in which increased aeration is desired. Consequently, silicone rubbers cannot be used where gas-tight seals are necessary.
Viton properties:
FKM's are serviceable in continuous heat of up to 250º C and intermittent heat of up to 300º C.
Satisfactory resistance to low temperatures of typically -20º C and - 40º C by use of special grades.
FKM's exhibit good flame resistance and are usually self extinguishing upon removal of flame source.
All FKM's have excellent resistance to oxygen, ozone and natural weathering.
FKM compounds have outstanding resistance to compression, especially at elevated temperatures.
Resistance to chemicals; amongst all synthetic rubbers FKM's are the most resistant to many of the solvents and chemicals, giving long service where other materials do not.
Excellent resistance against hydrocarbons, aliphatics, aromatic and chlorinated chemicals.
Good resistance to acids and alkali's including oxidants. Poor performance against ethers, ketones, and bases.
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