pros and cons of fluorine rubber
Thanks to their physical and chemical properties, technical gaskets made using fluorine rubber (FKM, FPM) have found applications in a series of industries, including aviation, automotive, food and petrochemical.
Below, we would like to describe the main pros and cons of gaskets made using the elastomer based on fluorine rubber colloquially referred to as Viton®.
Advantages of fluorine rubber:
Fluorine rubber gaskets are characterized by high temperature resistance.
The temperature range within which such gaskets can work ranges from -20°C up to as much as +250°C, which mainly depends on fluorine content in the mixture from which gaskets are made.
Another significant advantage of FKM is its swelling resistance. Resistance to swelling, similarly as in the case of temperature resistance, increases as fluorine content in the mix increases. Rubber swelling is a very undesirable phenomenon in the case of technical gaskets, which is associated with a sudden loss of the gasket’s mechanical properties due to solvent absorption in the polymer’s structure, by which the chain’s volume increases, causing swelling of the material.
Fluorine rubber (FKM/FPM) has a completely closed, stable main chain, thanks to which this material works perfectly in the production of o-rings, simmerings, sheets and other types of seals resistant to the action of mineral oils, aliphatic hydrocarbons (propane, butane, gasoline, natural gas), aromatic hydrocarbons (toluene, benzene), water, aqueous solutions, fats, sulfated oils, animal oils and fats, fuels, fuels containing methanol, non-organic acids (including sulphuric, hydrochloric, phosphoric acid) and many others.
Low gas permeability is another characteristic of Viton gaskets. It is small and comparable to the permeability of butyl rubber.
Other significant advantages of fluorine rubber are:
– resistance to oxidation
– resistance to atmospheric conditions
– resistance to ozone
– high resistance to aging
Cons of fluorine rubber gaskets
One of the biggest drawbacks of fluorine rubber (FKM/FPM) gaskets is their lack of resistance to polar solvents, which include acetone, ethyl acetate, dioxane, among others.
– Fluorine rubber also exhibits poor resistance to certain bases, including sodium hydroxide and potassium hydroxide, among others.
– Fluorine rubber displays poor resistance to water vapor.
Detailed data concerning the chemical resistance of fluorine rubber (FKM) can be found on our website in the resistances table. There, you can also compare the chemical resistances of Viton® (FKM/FPM) on the background of other materials such as: EPDM, NBR, SBR, Silicone, Teflon.