Molecular interaction and foaming property of the mixtures of hydrocarbon, fluorocarbon and silicone surfactants

Abstract

Fluorocarbon surfactants are inevitably involved in industrial applications in combination with hydrocarbon and silicone surfactants, but properties of the ternary mixed system of hydrocarbon, fluorocarbon and silicone surfactants have received little attention, especially foaming ability. In this study, surface activity and aggregation behavior of the ternary mixed system of anionic hydrocarbon (SDS), cationic fluorocarbon (FC-134) and nonionic silicone surfactants (OFX-5211) are studied systematically in order to investigate molecular interaction. Foaming ability of the ternary mixed system is evaluated by Ross-Miles method. Surface activity is characterized by surface tension. Aggregation behavior is obtained by using cryo-transmission electron microscopy (Cryo-TEM). The results show that intense interaction among molecules exists in the ternary surfactant mixture. FC-134 molecules show the interaction with other two surfactant molecules at air/liquid interface and strongest ability to absorb into air/liquid interface. Large vesicles of binary mixture of SDS/OFX-5211 are transformed into irregular micelles upon addition of FC-134. And wormlike micelles of binary mixture of SDS/FC-134 disappeared upon addition of OFX-5211. The foaming ability of the ternary mixtures is higher than that of any of individual surfactant or binary mixtures of surfactants. The intense interaction among molecules promotes the synergistic effect of foaming ability of the ternary mixtures. This study can provide a guidance for the scientific application of hydrocarbon, fluorocarbon and silicone surfactants.