The Synthesis Of Alkyl Imidazole Gemini Surfactant And Phase Behavior Study

The thesis contains four parts. Chapter I. Introduction. Chapter II. The phasebehavior and solubilization of microemulsion systems containing Geminiimidazoliums and their monomeric analogues. Chapter III. Comparison of thecomposition and structural parameters of W/O microemulsions containing Geminiimidazoliums with those containing Monomeric Analogues. Chapter IV. The phasebehavior and the solubilization of microemulsion systems containingCn（Bim）₂-2Br-SDS mixed surfactants.Chapter I. IntroductionThe chemical structures, properties and applications of Gemini surfactants wereintroduced. The research progress of this kind of surfactants were reviewed.Chapter II. Phase behavior and solubilization of microemulsionsystems containing Gemini imidazoliums and their monomericanaloguesIn this paper, an ε-β phase diagram method and an optimum microemulsiondilution method were used to investigate and compare the phase behavior ofmicroemulsion systems containing Gemini surfactants Cn（Bim）₂-2Br （n=12,14,16）/butan-1-ol/n-octane/brine, with that of the systems containing monomeric surfactantsCnmimBr, n=12,14,16)/butan-1-ol/n-octane/brine.1, A novel optimum Winsor III type microemulsion dilution method was used tocalculate the composition of the interfacial layer and both the solubilities of alcohol inaqueous and oleic phases, respectively.2, Cn（Bim）₂-2Br based microemulsion systems have smaller ASvalues （the massfraction of the alcohol in the interfacial layer） and greater solubilization ability thanthat of the corresponding mono surfactants CnmimBr based systems. Thesolubilization ability （SP*） increases as the carbon chain lengths of Cn（Bim）₂-2Brmolecules increase.3, The effect of NaCl concentrations on the composition of the interfacial layer （AS） and the solubilization ability （SP*） are similar in C12（Bim）₂-2Br based andC12mimBr based microemulsion systems. With the increase in NaCl concentrations inaqueous phase, a Winsor III type microemulsion would be formed and thesolubilization ability （SP*） would increase.4, The maximum solubilization ability （SP*） of both microemulsion systems wasattained when the values of α approach0.5.5, The solubility of the alcohol in aqueous phase in Cn（Bim）₂-2Br basedmicroemulsion systems is significantly greater than that in the oleic phase, and thealcohol is more soluble in Cn（Bim）₂-2Br based systems than that in CnmimBr basedsystems both in aqueous and oleic phases.Chapter â…¢.Comparison of the composition and structuralparameters of W/O microemulsions containing Geminiimidazoliums with those containing Monomeric AnaloguesThe composition and structural parameters of W/O microemulsions containingGemini surfactant Cn（Bim）₂-2Br （CnmimBr）/pentan-1-ol/n-octane/brine werestudied and compared.1, As the carbon chain length of the n-alkyl alcohol increases,bothX oaandX iawould decrease, whereas Δ Gooâ†'iwould increase. As the carbon chainlength of alkane molecules increases, bothX iaandX oawould increase,while Δ Gooâ†'ivalues would decrease.2, As NaCl concentration increases,X oaandX iawould decrease, whereas ΔGooâ†'iwould increase. This phenomenon can be explained by the salting-out effect.3, As temperature increases, the values ofX iafor both microemulsion systemswould increase, whereasX oawould decrease, resulting in an increase in ΔGooâ†'ivalues. Chapter IV. The phase behavior and solubilization ofmicroemulsion systems containing Cn（Bim）₂-2Br-SDS mixedsurfactants.The phase behavior and solubilization of microemulsion systemsC12（Bim）₂-2Br-SDS/butan-1-ol/n-octane/5%NaCl aqueous solution wereinvestigated systematically.1, The middle-phase microemulsions would form at theX Cn（Bim）₂-2Brrange of0-0.1and0.7-1.0. Cn（Bim）₂-2Br-SDS based microemulsion systems show superiorsynergetic solubilization ability （SP*） than those of individual Cn（Bim）₂-2Br and SDSbased microemulsion system.2, Temperature has a significant influence on C12（Bim）₂-2Br-SDS （molar ratio7:3）/butan-1-ol/n-octane/5%NaCl aqueous solution microemulsion systems.3, As NaCl concentrations in aqueous phase increase, the solubilization ability（SP*） of the microemulsion systems increases.