Research On The Synthesis And Charateristics Of Sodium Di-Linear Alkyl Diphenyl Ether Disulfonate

The choice of reaction conditions, the purificated procedure of the products, the characterization and the surface chemistry property of sodium di-linear alkyl diphenyl ether disulfonate (DLADS) have been studied in this paper.Sodium di-linear alkyl diphenyl ether disulfonate have been firstly synthesized from lauric acid, myristic acid and cetylic acid as raw materials after five-step reactions such as acidation, Friedel-Crafts acylation, Clemmensen reduction, sulfonation and neutralization reaction. The structures of Gemini surfactants were characterized by IR spectrometry, UV spectrometry, MS, 1H-NMR and elemental analysis and so on. After optimization, the best reaction conditions of Friedel-Crafts acylation were showed as follows: molar ratio of diphenyl ether to lauryl chloride is 1:2.5, molar ratio of lauryl chloride to alchlor is1:1.35, reaction time is 16h and reaction temperature is 20℃. The transesterification yield can be up to 98%. After the monofactorial experiment, the reaction conditions of Clemmensen reduction are showed as follows: the molar ratio of mercuric chloride to zinc dust is 1:60, reaction time is 8h, the molar ratio of hydrochloric acid to zinc dust is 6:1 and the total hydrochloric acid was added in five different lots. The yields of Clemmensen reduction is 70.2%, and the yield of the C12-DLADS is 49%.Air-Liquid sueface tension of DLADS were measured by using Du Nouy method at the tremperature of 318K. It implied that the values of cmc increased from 0.19×10^-4mol/L to 6.03×10^-4mol/L, andγcmc increased from36.04 mN·m^-1 to 42.98 mN·m^-1. It showed perfect surface chemical properties, dissolution, solubilization and emulsification and other application performance.The electric conductivity of the C12-DLADS solutions was measured at 298.0±0.1, 308.0±0.1 and 318.0±0.1K respectively. The results showed that with increasing temperature, the conductivity of C12-DLADS was increased, while the antiparticle binding K0 was decreased. The theoretical derivation of ionic strength showed that DLADS solutions is triple ionic intensity of anionic surfactants solutions. The thermodynamic data showed that the micellization process for the surfactant C12-DLADS is entropy driven.