Synthesis And The Physical Chemistry Properties Of Taurine Ionic Liquids

Ionic liquid is a new environmental protection solvent because of its wide liquid temperature range,good stability,low vapor pressure and non-flammability.It has received wide attention.In this paper,1-ethyl-3-methylimidazole taurine（[C₂mim][Tau]）and1-（4-methoxybutyl）-3-methylimidazoletaurine（[COC₄mim][Tau]）were synthesized by a two-step synthesis method.In order to determine the samples as the target products,thus samples were characterized and analyzed by ¹H NMR and ¹³C NMR spectrum.Firstly,according to the standard addition method,in this paper,the physicochemical properties of the density,surface tension and refractive index for[C₂mim][Tau]and[COC₄mim][Tau]were measured at different temperatures.The volume and surface properties of taurine ionic liquids were systematically studied.According to Glasser‘s classic theory,surface entropy and lattice energy of[C₂mim][Tau]and[COC₄mim][Tau]were calculated,and the surface entropy and surface energy of taurine ionic liquids were obtained.Secondly,using Rebelo and Kabo theoretical models,the vaporization enthalpies of[C₂mim][Tau]and[COC₄mim][Tau]were estimated,and the reasons for the difference in the estimated vaporization enthalpies of two theoretical models were analyzed in detail.In addition,combining the definition of the molar surface Gibbs energy with Lorentz-Lorenz empirical equation,the surface tensions of two taurine ionic liquids were predicted,and their predicted values were in good agreement with the corresponding experimental values.