Synthesis And Properties Of Dissymmetry Nonionic-anionic Gemini Surfactants

With the development of science and technology, the traditional surfactants cannot satisfy people’s life and needs, many new surfactants have been emerged, includingGemini surfactant. The dissymmetry Gemini surfactant show many excellentproperties than symmetry Gemini, such as high surface activity, low critical micelleconcentration （cmc）,so many researchers focus on it. In this paper, the three kinds ofnonionic-anionic dissymmetry gemini surfactants （XSOHC_n,n=6,8where n representsthe hydrocarbon chain length of aliphatic amine） were synthesized from cyanuricchloride, three different kinds of fatty amine, taurine and ethanolamine. The structuresof the aimed products were identified by1H NMR, ESI-MS, IR and elementalanalysis.The surface active of the three kinds of dissymmetry Gemini Surfactants weremeasured by Surface tension and steady-state fluorescence methods, the micellesformation thermodynamic processes of the dissymmetry Gemini Surfactants weremeasured by electric conductivity method. The result shows that the properties ofXSOHC_nare superior to those of symmetry Gemini Surfactants XCnand SDS,such asthe γcmc and cmc of XSOHC₈are28.2mN/m and2.1×10^-6mol/L respectively. With thetemperature increases the β decreases, thermodynamic parameters of micellizationderived from electrical conductivity indicate that the micellization of XSOHC_nisentropy-driven.The dynamic surface tension （DST） of dissymmetry Gemini Surfactants weremeasured by the haning drop method, discussed the impact of concentration,adsorption model and the dynamic adsorption mechanism.The adsorption process iscontrolled by diffusion at the start and in the end,the adsorption process of the mid iscontrolled by hybrid dynamics.The micelle aggregation number and the averagehydrodynamic radius of the micelles of the dissymmetry Gemini Surfactants weremeasured by fluorescence quenching method and dynamic light scattering method. The result show that with the growth of the alkyl chain, its micellar aggregation number（N_m） increased,the micelle hydrodynamic radius increased with the concentration（above cmc） increased.The emulsification of the three kinds of dissymmetry Gemini surfactantsits weremeasured by cylinder method，the solubilization ability of its were measured by UVspectrophotometry method,the wetting ability of its wetting ability were measured byhooks method.The emulsification stability of these Gemini surfactants is excellent;XSOHC₈is more superior than others in the efficiency of solubilization of thepolycyclic aromatic hydrocarbons （pyrene and anthracene）.