Effect Of The Interaction Between A Partially Fluorinated Gemini Surfactant And Polymer

Gemini surfactants are a new class of surfactants which possess two amphipilic moieties connected by a spacer group, presenting lower critical micelle concentration (CMC) and surface tension than the conventional single-chain surfactants. Fluorinated surfactants are receiving much attention due to their special properties, such as a remarkably low critical micelle concentration, a high efficiency in reducing the surface tension, outstanding chemical inertness and thermal stability. However, reports on the fluorinated Gemini surfactants are much less in number compared to hydrocarbon Gemini surfactants. Much attention should be devoted to this study.Mixtures of surfactants and polymers in aqueous solutions are widely used in industrial applications such as oil recovery, cosmetics, and detergency. There has been more than 60 years since people first did the research on the interaction between surfactant and polymer. However the studies mainly focus on the interaction between hydrocarbon surfactant and polymer, but there are few studies involve fluorinated surfactants. There must be much significance on the study of interaction between fluorinated Gemini surfactant and polymer.The properties of partially fluorinated Gemini surfactants named N,N-bis(3-perfluorohexyl-2-hydroxypropyl)-N,N-dipropanesulfonylhexylenediamine (N-6-Sul) in aqueous solution, were investigated through surface tension and RLS measurements. The results show that:the CMC of N-6-Sul is 2-3 orders of magnitude is lower than the traditional single-chain surfactants; the value of the surface tension at CMC is also lower than traditional surfactants; N-6-Sul presents good salt tolerance, temperature resistance, alkali-resisting but not acid-resisting. The CMC value determined by fluorescence method is consistent with that measured by surface tension. In addition an unusual response of pyrene fluorescence is observed in the steady-state fluorescence measurements. TGA measurement shows that N-6-Sul began to decompose above 300 ℃, presenting excellent thermal stability.The interaction between partially fluorinated Gemini surfactant N,N ’-bis(3-perfluorohexyl-2-hydroxypropyl)-N,N’-dipropanesulfonylhexylenediamine (N-6-Sul) and partially hydrolyzed polyacrylamide (HPAM) was investigated using surface tension, resonance light scattering method, fluorescence and viscosity measurements. The interaction between N-6-Sul and HPAM shows synergistic effect because of the unique nature of the partially fluorinated Gemini surfactant. Due to the interaction in the N-6-Sul/HPAM system, the mixed solutions show many advantages such as high surface activity, great salt tolerance, viscosity enhancement and lower costs than the pure fluorinated Gemini surfactant. The study of the N-6-Sul/HPAM mixture provides the opportunity for realizing the interaction between surfactant and polymer, and will broaden our vision on developing surfactant system with high performances and processability in the future.