Ultrasonic-microwave synthesis of polyoxyethylenated stearyl ether maleic acid diester gemini surfactants

摘要

Polyoxyethylenated stearyl ether maleic acid diesters (PSME-n) have been synthesized through esterification of maleic anhydride and polyoxyethylenated stearyl ether (n) (PSE-n) using an ultrasonic-microwave technique. The resulting products were characterized by FTIR and H-1-NMR. Inference of the reaction conditions, such as microwave power, ultrasonic power, temperature and reaction time, were evaluated. The optimal conditions are as follows: n (PSE): n (MA) = 2:1, catalyst p-toluene sulphonic acid (TsOH) 3 %, reaction temperature 130 A degrees C, microwave power 400 W, ultrasonic power 180 W and reaction time 60 min. Under the optimal conditions, the esterification rates of the series of products have reached up to 89-92 %. The results showed that the ultrasonic-microwave technique is able to greatly shorten the time and reduce the temperature of this esterification reaction. The surface properties, particle size and morphology of the micelles of PSE-15 and PSME-15 were investigated by surface tensiometer and FESEM.