Polyfluoroalkyl

Polyfluoroalkyl refers to chemical groups and compounds in which hydrogen atoms on an alkyl chain have been partially replaced by fluorine atoms, yielding multiple carbon–fluorine bonds. The term is commonly used within the broader category of PFAS, or poly- and perfluoroalkyl substances. Polyfluoroalkyl denotes chains that are not fully fluorinated, whereas perfluoroalkyl describes fully fluorinated chains. Together, PFAS encompasses thousands of individual substances with related structures and properties.

These compounds exhibit high chemical and thermal stability, strong resistance to water and oil, and very low surface energy. Such characteristics enable a wide range of industrial and consumer applications, including water- and stain-repellent coatings for textiles and leather, nonstick surfaces in cookware, fire-fighting foams, paper and packaging coatings, electronics, and various industrial lubricants.

Environmental and health considerations arise from the persistence and mobility of polyfluoroalkyl compounds. The strong C–F bonds resist natural degradation, allowing them to persist in soils, sediments, and aquatic systems and to spread over long distances. Some polyfluoroalkyl substances can accumulate in living organisms and have been associated, in studies, with various health effects, though risk varies by compound and exposure level. Public and regulatory attention has grown to better manage risks, improve monitoring, and reduce releases.

Regulatory approaches vary by country but commonly involve limits on emissions and drinking-water concentrations, phaseouts or restrictions of specific substances, and the promotion of safer alternatives. Remediation strategies for contaminated media include activated carbon adsorption, ion-exchange processes, advanced membrane technologies, and, in some cases, controlled high-temperature destruction to break persistent bonds.