Synthesis of Polyoxyethylene (n) Stearyl Ether Sodium Sulfosuccinate by Ultrasonic-Microwave Co-Irradiation Technology

The objective of this study was to develop an efficient technique for enhancing the synthesis of sulfosuccinic acid diester sodium salt, required for industrial purposes. A series of gemini surfactants containing two symmetrical nonionic groups and an anionic moieties (polyoxyethylene stearyl ether sodium sulfosuccinate: PSSE-n) are synthesized via additive reaction of the double bond with sodium hydrogen sulfite under ultrasonic-microwave co-irradiation in solvent-free process. The structure of products is confirmed by FT-IR and 1H NMR. Sulfonation reaction conditions are discussed by single factor method. The optimal sulfonation reaction conditions are as follows: (i) n (maleic acid diester): n (sodium hydrogen sulfite) =1:1, (ii) microwave / ultrasonic power of 300 W / 360 W, (iii) reaction temperature 70°C, reaction time 60 min. Under the optimal conditions, series of products have reached up to a sulfonation rate of 75%-80%. The sulfonation reaction temperature drops by 22°C-25°C and the reaction time reduces for 35 hours comparing to the conventional approach.