Perfluorinated Surfactants in Aqueous Media: Interactions Leading to Association and Dissociation

Perfluorinated surfactants find niche applications because of their high chemical and thermal stability, their incompatibility with both water and hydrocarbons, and their unique ability to render surfaces non-stick. However, several widely used perfluorinated surfactants have been found extremely resistant to degradation, accumulate in the environment, and have long half-lives in humans, consequently causing great concern. In the context of sequestering perfluorinated surfactants from aqueous media, we research solution properties of fluorinated surfactants, with a focus on how such surfactants interact with (bind to) other molecules or particles/surfaces. We report here on ammonium perfluorooctanoate (PFOA) micelle formation and structure in aqueous solutions and micelle dissociation in the presence of various additives, probed with complementary experimental techniques (conductivity, surface tension, small-angle neutron scattering) and atomistic simulations. [Kancharla, S.; Canales, E.; Alexandridis, P., Int. J. Mol. Sci. 2019, 20 (22), 5761. DOI: 10.3390/ijms20225761] The results inform the fate and transport of per- & poly-fluoroalkyl substances (PFAS) in the environment.