Physicochemical Properties of Short-Chain-Fluorocarbon Surfactant Compounded with an Extended Hydrocarbon Surfactant in Aqueous Solutions

In this study, a short-fluorocarbon zwitterionic surfactant (FC63) was synthesized by amidation and quaternization of perfluorohexane sulfonyl fluoride. A systematic study on the surface activity, aggregation behavior, and foaming performance of mixtures containing FC63 and an extended hydrocarbon surfactant (C12P6E3S) was conducted. The results show that the FC63/C12P6E3S mixtures exhibit a synergistic effect in forming mixed micelles and lowering critical micelle concentration (CMC) (10^-2 mmol/L). And the surface tensions of mixed systems are lower than that of the hydrocarbon surfactant. The average values of micelle interaction parameter β^<i>m</i> and surface interaction parameter β^σ are -8.84 and -9.5, respectively, indicating that the formation of micelles in solution and absorption at the surface are spontaneous, and the adsorption process is easier than micellization. Moreover, there is a synergistic effect in enhancing the foaming capability and foam-stabilizing ability of FC63/C12P6E3S with an appropriate molar ratio. Adding a small amount of FC63 increases the foamability of the mixed solution and decelerates the drainage and coarsening speed of the FC63/C12P6E3S foams. This work presents a surfactant mixture based on short-chain fluorocarbon surfactant with reduced environmental risk and extended hydrocarbon surfactant and provides a deep insight into the interaction at different compounded molar ratios.