Fluoroether Double-Chain Phosphate Surfactants: An Exploration of Alternatives to Fluorotelomer Surfactants.

While legacy fluorosurfactants have already been categorized as persistent organic pollutants, there appeared to be many strategies to develop alternatives. In this work, fluoroether double-chain phosphate surfactants (C72 diPAP-Na and C72 diPAP-NH 4 ) were designed and synthesized with the initial intention of exploring the creation of new fluorosurfactants containing oxygen heteroatoms in the fluorocarbon chain segments to provide an alternative to the legacy long-chain fluorosurfactants. Furthermore, it was expected that they would even exceed the existing 6:2 fluorotelomer surfactants (6:2 diPAP-Na and 6:2 diPAP-NH 4 ). Compared with characterizations of surface activity, foam performance, and wettability, the results showed that each of them has its own distinctive performance. Although the C72 series as new fluoroether surfactants cannot fully replace the 6:2 series of fluorosurfactants in terms of performance, there is a possibility of substitution in some aspects, which is of positive significance for further exploration to improve alternatives to legacy fluorosurfactants.