Study on the properties of amide Gemini surfactants

Abstract In this study, the properties of amide Gemini surfactants (DLP-12, DLP-14 and DLP-16) were investigated. The results showed that these surfactants have good wettability and solubility, but these properties deteriorate with increasing hydrophobic chain length. The critical micelle concentrations (CMC) measured by the Wilhelmy method and by the steady-state fluorescence spectroscopy were similar and showed the same trend: The CMC values decreased with increasing hydrophobic chain length. The solubilization capacities in toluene were (6320, 6440 and 6680) mL/mol for DLP-12, DLP-14 and DLP-16, respectively, indicating an improvement in solubilization ability. Thermal stability experiments showed that the initial decomposition temperatures of the three surfactants were (301, 320 and 331) °C, respectively, indicating good thermal stability of these surfactants.