¦¥-beta Fish-shaped Phase Diagram Research Yin, Cationic Surfactants And Its Complex System Of Middle Phase Microemulsion,

This thesis contains five parts. Part I. Progress in the research of the phase behaviour of microemulsion; Part II. Studies on the middle phase microemulsion formed by anionic surfactant withε-βfishlike phase diagram; Part III. Studies on the middle phase microemulsion formed by cationic surfactant withε-βfishlike phase diagram; PartⅣ. Studies on the phase behaviour of the microemulsion formed by anionic and cationic composite surfactants; PartⅤ. Studies on the microemulsion formed by the composite surfactants of nonionic surfactant and ionic surfactant.Part I. Progress in the research of the microemulsion phase behaviourThe formation, classification and the phase inversion of microemulsion systems were introduced. Three phase diagrams: Winsor phase diagram,δ-γfishlike andε-βfishlike phase diagrams were introduced and evaluated. From Winsor phase diagram, the phase inversion, the volume of each phase, and the salt width or alcohol width of the microemulsion system can be observed visually. But the composition of the interfacial layer and related chem-physical parameters can not be obtained .δ-γfishlike phase diagram is often used to calculate the composition of the interfacial layer and related chem-physical parameters. However, it can't offer the accurate values and it is inconvenient to discuss the solubilization power of the system.The composition of the interfacial layer and related chem-physical parameters can be precisely calculated fromε-βfishlike phase diagram, and this phase diagram can be used to evaluate the solubilization power of the microemulsion conveniently.Part II. Studies on the middle phase microemulsion formed by anionic surfactant withε-βfishlike phase diagram The phase behavior and the influencing factors of quaternary AS (SDS, SDBS) / alkane / alcohol / NaCl solution microemulsion system were studied withε-βfishlike phase diagram.(1) For quaternary microemulsion systems of AS (SDS, SDBS) / n-octane / n-butanol / 5.0% NaCl solution, the order of the solubilization power is SDBS >> SDS > AS. The molecule of SDBS contains phenyl group, which increases the solubilization power of its microemulsion system.(2) NaCl concentration has great influence on the solubilization power of the quaternary microemulsion system. With the increases in the mass fraction of NaCl in aqueous phase, the solubilization power of the microemulsion system increases and the amount of alcohol needed to form single phase microemulsion decreases.(3) The main factor influencingε-βfishlike phase diagram of inorganic salts is the anti-ions (such as K+). Fix K+ concentration and change anion ions, theε-βfishlike phase diagram changes a little.(4) The alkane order of the solubilization power is n-hexane > n-octane >n-dodecane. That is, the oils with short carbon chain lengths are of high solubilization power of their microemulsions.(5) The longer the carbon chain length of the alcohol is, the larger the solubilization power of their microemulsion is.Part III. Studies on the middle phase microemulsion formed by cationic surfactant withε-βfishlike phase diagramThe phase behaviors of CTAB (CPB) / alcohol / alkane / aqueous solution were studied byε-βfishlike phase diagram.(1) For quaternary microemulsion systems of CTAB(CPB) / alcohol / alkane / aqueous solution, The solubilization power order is CTAB > CPB.(2) With the increase in the mass fraction of NaCl in aqueous phase, the amount of alcohol (εE) used to form single phase microemulsion decreases, and the solubilization power of the microemulsion system increases.(3) The longer the carbon chain length of alkane is, the more the alcohol needed to form middle phase microemulsion is. The solubilization power order is n-hexane > n-octane > n-dodecane.(4) The hydrophobicity of the alcohol increases with its carbon chain length increases, and the ability to form middle phase microemulsion and the solubilization power increase.Part IV. Studies on the phase behaviour of the microemulsion formed by anionic and cationic composite surfactantsThe phase behaviour of the microemulsion formed by anionic and cationic composite surfactants was studied byε-βfishlike phase diagram.(1) Synergistic effect was found between anionic and cationic surfactants in the formation of microemulsion. If anionic and cationic surfactants were mixed at non-equal mole ratio, the solubilization power of their microemulsion increases and no deposit appears.(2) The charge at the surface of the O/W microemulsion droplets is mainly determined by the excessive surfactant in the mixed system. The higher the concentration of the anti-ions is, the stronger the ability for the anti-ions to compel the double electric layer is, and the larger the solubilization power of the microemulsion system is.(3) The smaller the alkane molecule is, the easier for it to penetrate the interfacial layer is, so the larger the solubilization power of the microemulsion system is.PartⅤ. Studies on the microemulsion formed by the composite surfactants of nonionic surfactant and ionic surfactantThe phase behaviour of the microemulsion formed by the composite surfactants of nonionic surfactant and ionic surfactant was studied withε-βfishlike phase diagram. (1) Nonionic surfactant alkyl polyglucoside (APG) is mixed with ionic surfactant SDS or CTAB at different mole ratios, getting the composite surfactants. The solubilization power of the microemulsion formed by the composite surfactants is larger than that of the single surfactant microemulsion system.(2) Fixing the mole ratio of APG/SDS=7:3, the influences of salt concentrations, oils and alcohols on theε-βfishlike phase diagram were examined. It was found that the influence is the same as that in the single surfactant microemulsion system.