In order to explore alternative substances for traditional fluorocarbon surfactants while maintaining high surface activity, this study successfully designed and synthesized an organosilicon surfactant (SiCH) containing a hydroxyl quaternary ammonium salt. Its molecular structure was confirmed by Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR), and mass spectrometry (MS). This surfactant exhibits excellent thermal stability, with an initial decomposition temperature of 167 °C and minimal residue at high temperatures. The critical micelle concentration (CMC) and the surface tension (γ CMC) at the CMC of SiCH are 9.10 mmol/L and 22.81 mN/m, respectively. The organosilicon surfactant-sodium hexanesulfonate (SiCH-SHS) exhibits significant synergistic effect, reducing the CMC and γ CMC to 6.88 mmol/L and 21.03 mN/m respectively. The area occupied by a single surfactant molecule at the air/water interface (A S) of the SiCH-SHS is 1.24 nm2, and the pC20 is 2.91. The size distribution of SiCH is unimodal, and they can self-assemble into non-uniform sized spheroidal aggregates (122-295 nm). Moreover, the thermodynamic process of micelle formation of the surfactant was studied through conductivity tests conducted at different temperatures (298.15 - 303.15 K). Thermodynamic analysis indicates that micellization is a spontaneous ( Δ G m 0 <0), entropy-driven process.
Zhu et al. (Fri,) studied this question.