Synthesis and performance of novel quaternary ammonium surfactants containing multifunctional group and organic counterions

Four novel quaternary ammonium surfactants containing ethoxy, amide and organic counterions were synthesized using glycolic acid ethoxylate oleylether, N , N -dimethylethylenediamine, dimethyl carbonate and carboxylic acids as raw materials and characterized with the aid of 1 H NMR, 13 C NMR and FTIR spectroscopy. The results indicated that their Krafft temperature was below 0 °C. Thermogravimetric analysis revealed that all four surfactants were highly thermally stable with T start of 323.65–359.65 °C and T onset of 390.29–394.65 °C. The results also showed that the surfactants had excellent surface activity with the critical micelle concentration of 2.70 × 10 −6 ∼ 4.61 × 10 −5 mol·L −1 and the corresponding surface tension of 31.03–34.09 mN·m −1 , and self-assemble spontaneously into the rod-like micelles at lower concentrations. Furthermore, according to the relationship between the relative growth rate of cells and the grade of cytotoxicity in the XXII Pharmacopoeia of the United States, the cytotoxicity grade of the four surfactants on L929 cells was 0 or 1, suggesting noncytotoxicity.