Aqueous film forming foam (AFFF) is the state-of-the-art technology available today to fight against liquid fuel pool fires. AFFFs traditionally contain perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS). These chemicals have the strongest chemical (carbon-fluorine) bonds and are considered persistent, bio-accumulative, and toxic (PBT) substances. PFOA/PFOS chemicals have leached into groundwater and were detected around the world in the food chain, drinking water, animals, and even in human blood. Due to their ubiquitous presence in the environment and the increasing concern of their toxicological effects, efforts have been focused on reducing exposure to these “Forever” chemicals. Recently, the Environmental Protection Agency, EPA has regulated the chemical industry for the complete elimination of PFOA and PFOS chemicals. The regulation on PFOA/PFOS chemicals is directly affected by the AFFF industry. Therefore, we are working on environmentally acceptable alternatives for use on militarily relevant fuels, to meet the performance requirements of the MIL-F-24385F standard.
The new materials systems to reduce the surface energy and the ability to form a stable water film over the flammable fluids were synthesized, and their foam foaming abilities were measured. The resulting fluorine-free surfactants formed a stable foam layer on top of liquid fuels (Heptane, Jet A, and Gasoline) and acted as a barrier for combustible liquids from supplying fuel vapor to the fire.