fluoroelastomers

Fluoroelastomers are a family of synthetic elastomers in which a substantial portion of the hydrogen in the polymer backbone is replaced by fluorine. This chemistry gives high resistance to heat, fuels, oils, solvents, and many chemicals, along with low permeability. The most widely used member is fluorinated elastomer, commonly referred to as FKM or fluoroelastomer, and it is frequently marketed under trade names such as Viton.

FKMs are typically copolymers based on vinylidene fluoride (VDF) with comonomers such as hexafluoropropylene (HFP), and may also include tetrafluoroethylene (TFE) or perfluoromethyl vinyl ether (PMVE). These variations tailor properties for different service conditions, including temperature range, chemical exposure, and compression set. FEPM is another fluorinated elastomer family that incorporates additional monomers to achieve specialized performance. Collectively these materials are chosen for demanding seals, gaskets, O-rings, and other dynamic interfaces.

Processing and curing of fluoroelastomers generally rely on peroxide-based systems or specialty cure chemistries that promote crosslinking without compromising chemical resistance. Typical service temperatures span roughly from subzero to around 200–250 C, depending on formulation, while providing excellent resistance to hydrocarbons, fuels, many solvents, and ozone.

Applications span automotive engines and fuel systems, aerospace, chemical processing, and general industrial sealing under harsh chemical and thermal conditions. Limitations include higher material cost, reduced low-temperature flexibility relative to some other elastomers, and potential swelling in certain ketones or esters at elevated temperatures.