Synthesis, Characterization and Properties of N-Alkyl-N,N-di(2-hydroxyethyl) Amine Oxides

摘要

N-Dodecyl-N,N-di(2-hydroxyethyl) amine oxide (C(12)DHEAO) and N-stearyl-N,N-di(2-hydroxyethyl) amine oxide (C(18)DHEAO) were synthesized with N-alkyl-diethanolamine and hydrogen peroxide. Their chemical structures were confirmed using H-1-NMR spectra, mass spectral fragmentation and FTIR spectroscopic analysis. It was found that C(12)DHEAO and C(18)DHEAO reduced the surface tension of water to a minimum value of approximately 28.75 mN m(-1) at concentration of 2.48 x 10(-3) mol L-1 and 32.45 mN m(-1) at concentration of 5.21 x 10(-5) mol L-1, respectively. The minimum interfacial tension (IFTmin) and the dynamic interfacial tension (DIT) of oil-water system were measured. When C(18)DHEAO concentration was in the range of 0.1-0.5%, the IFTmin between liquid paraffin and C(18)DHEAO solutions all reached the ultra-low interfacial tension. Furthermore, their foam properties were investigated by Ross-Miles method, and the height of foam of C(12)DHEAO was 183 mm. It was also found that they showed strong emulsifying power.