Construction Of Ionic Liquid Surfactant Micelles

The ionic liquid surfactant micelles have not only inherent micelle properties itself but also some special unique properties of ionic liquid. The ionic liquid surfactant micelles were constructed through two methods: synthesis ionic liquid and micellizated it directly; complex micelle was constructed with surfactant and ionic liquids.From hydroxyl type ionic liquid [C2OHmim][PF6], adding propylene oxide to the hydroxyl to get [C2OHmim][PF6] propylene oxide product, and the characterization has been done by MS. Surface tensions of [C2OHmim][PF6] and [C2OHmim][PF6] propylene oxide product were determinated by drop volume method to assess the surface activity of alkoxylation products.Long-chain alkyl imidazole ionic liquid chloride 1-(2-hydroxyethyl)-3-dodecyl midazolam was synthesized and characterized by infrared Spectrum. Its critical micelle concentration was determinated by surface tension method, conductivity method and steady fluorescence method. The micellar aggregation number(Nagg) was and its change law with concentration change by The steady-state fluorescence quenching method.Two kinds of ionic liquids [C2OHmim][PF6],[C2OHmim][Cl] and typical anionic surfactant LAS,SDS were chosen respectively as working object, the mixed micelle was constructed by ionic liquid-surfactant micelle binary complex. On the basis of investigation possibility of ionic liquid and surfactant micelle forming mixed micelle, the possible change of structure and application properties of ionic liquid-surfactant micelle mixed micelle was also studied.All the experiment results and conclusions of this paper were summarized as follow: (1) The possibility of preparing surfactant type ionic liquid was attempted successfully: the epoxy propane derivative reaction of hydroxyl type ionic liquid [C2OHmim][PF6] and its intermediate [C2OHmim][Cl] was realized successfully; the hydrophobic group chain length of [C2OHmim][PF6] was changed to synthesis long-chain alkyl hydroxyl type imidazole ionic liquid [C2OHC12im][Cl].(2) Theγ-lgc curve of [C2OHC12im][Cl] aqueous solution has similar phenomenon that platform after inflexion as typical surfactant micelles, indicating that [C2OHC12im][Cl] has significant surfactant micelles characteristics; the cmc andγcmc of [C2OHC12im][Cl] solution were determinate by surface tension method, conductivity method and steady fluorescence method.(3) A experimental method was constructed using steady-state fluorescence quenching to determinate the average micellar aggregation number of [C2OHC12im][Cl] by pyrene fluorescence probe and benzophenone as quencher. The aggregation number of micelle is linear with the concentration for [C2OHC12im][Cl] in the concentration range of 9.55-13.20 mmol/L: Nagg = 1.67c + 20.25 (R2=0.9609). Ncmc was calculated and was 24.4.(4) Construct the complex micelle for [bmim][PF6] and SDS ,and prove the existence of it through UV absorption spectroscopy and fluorescence spectroscopy;The the [bmim][PF6] in composite micelles of [bmim][PF6]–SDS should be located in the micelle fence layer of SDS; The solubilization amount of n-octanol for the SDS-[bmim][PF6] composite micelles increases obviousely.(5) The variation of cmc for the binary mixed systems of [C2OHmim][Cl]-LAS and [C2OHmim][Cl]-SDS versus the proportion of [C2OHmim][Cl] in LAS,SDS aqueous solutions have been investigated, and found that the cmc andγcmc values achieve maximum at the same time when the proportion of [C2OHmim][Cl] in aqueous solutions was 0.5.(6) A experimental method was constructed using steady-state fluorescence quenching to determinate the average micellar aggregation number of binary mixed systems of [C2OHmim][Cl]-traditional anionic surfactant by pyrene fluorescence probe, benzophenone as quencher. The aggregation number of micelle is linear with the concentration for the system of [C2OHmim][Cl]-LAS when the molar ratio was 1:1 in the concentration range of 4.15×10-4~6.0×10-4mol/L: Nagg = 2.1029c + 30.877(R2=0.9975);The aggregation number of micelle for the composite system of [C2OHmim][Cl]-LAS (the molar ratio was 1:1) was 31, and larger than LAS, this is correlative with that the [C2OHmim]+ reduce the electrostatic exclusion of LAS.(7) The possible ways of interaction for water soluble ion liquid of [C2OHmim][Cl] and typical anionic surfactants LAS and SDS have been investigated:...