Study on Oil Resistance of Fluorine‐Free Foam Stabilized by the Mixture of Hydrocarbon and Silicone Surfactants

ABSTRACT It is urgently necessary to develop a highly stable fluorine‐free foam system. Optimizing the mixture of surfactants is the key to improving the stability and oil resistance of the foam. This paper systematically studied the application of a binary mixed system composed of non‐ionic hydrocarbon surfactants (alkyl glucoside, APG‐0810) and two non‐ionic organic silicon surfactants (CoatOsil‐77 and UF‐5811) in the oil resistance of fluorine‐free foams. Under both oil‐free and oil‐containing conditions, the surface tension, conductivity, viscosity, foaming ability and oil resistance were evaluated. Adding n‐heptane through micro emulsification increased the surface tension; the conductivity increased in AC# and AU#, while it decreased in CU#. The foaming ability of AC#, AU#, and CU# decreased by 50%, 36.1%, and 75% respectively, and the foam half‐life decreased by 40.5%, 50%, and 82.6% respectively. Among them, the AC# system exhibited the best oil resistance, and the liquid film stability persisted for 150 s under oil‐containing conditions. The mixture of APG‐0810/CoatOsil‐77 showed excellent performance, providing a theoretical basis for the design of stable fluorine‐free oil‐resistant foams.