Perfluorinated compound

A perfluorinated compound (PFC) is an organofluorine compound with all hydrogens replaced by fluorine on a carbon chain—but the molecule also contains at least one different atom or functional group. Thus, PFCs have properties similar to fluorocarbons (a wholly carbon and fluorine containing compound) as they are fluorocarbon derivatives. They have unique properties to make materials stain, oil, and water resistant, and are widely used in diverse applications. PFCs persist in the environment as persistent organic pollutants, but unlike PCBs, they are not known to degrade by any natural processes due to the strength of the carbon–fluorine bond.^[1]

Examples

There are many PFCs, but the two most studied^[2] compounds are:

• PFOA or perfluorooctanoic acid, used to make fluoropolymers such as Teflon, among other applications.
• PFOS or perfluorooctanesulfonic acid, used in the semiconductor industry, 3M's former Scotchgard formulation, and 3M's former fire-fighting foam mixture.

Other PFCs include:

• PFNA or perfluorononanoic acid, used as surfactant in the emulsion polymerization of fluoropolymers, like PFOA.
• PFBS or perfluorobutanesulfonic acid, used as a replacement for PFOS in 3M's reformulated Scotchgard.
• POSF or perfluorooctanesulfonyl fluoride, used to make PFOS-based compounds.
• PFOSA or perfluorooctanesulfonamide, formerly used in 3M's Scotchgard formulation.
• FC-75, a 3M Fluorinert liquid and perfluorinated cyclic ether.

PFOS and POSF are included within Annex B of the Stockholm Convention on Persistent Organic Pollutants.

Polyfluorinated compounds, such as fluorotelomers, can serve as precursors that degrade to form perfluorinated carboxylic acids, such as PFOA and PFNA.

See also

• Fluorosurfactants
• Fluorocarbons

References