Synthesis, characterization and surface-activity of a polyoxyethylene ether trimeric quaternary ammonium surfactant

A trimeric quaternary ammonium salt surfactant containing polyoxyethylene chains was synthesized from fatty alcohol polyoxyethylene ether, pentamethyldiethylenetriamine and thionyl chloride by a twostep process. Its chemical structure was characterized, and the surface activity in aqueous solution was studied at different temperatures. The results showed that when the concentration attains the CMC (1.0 mmol/L), the surface tension is 38.9 mN m^-1 and the conductivity is 105.3μS cm¹-at 25 °C. These show that the trimeric quaternary ammonium salt surfactant containing polyoxyethylene chains exhibits high surface activity and effectively reduces the surface tension of water.