Self-Organized Assemblies of Surfactants Derived from Ethanolamines

Abstract

The aggregation behavior of some novel functional surfactants (synthesized from ethanolamines and alkyl bromides) in aqueous medium and on water-air interface has been investigated. Single-tailed surfactants derived from quaternization of triethanol amine and tetradecyl and hexadecyl bromide form micelles with CMC values around 0.07–0.5 mM while the gemini surfactants derived from diethanol amine, hexadecyl bromide and dibromoalkanes are found to aggregate in the range of 0.3 to 0.56 mM. The surface pressure-area isotherms of the water insoluble N-alkyldiethanolamine and the corresponding double tailed surfactants and gemini surfactants were obtained on water surface. The effect of alkali, acid and salts in the water subphae on the area/molecule was investigated. The different values of area/molecule on the water surface have been attributed to different structures of the head group on water and in presence of additives.

Keywords:

• Area/molecule
• CMC
• ethanolamine
• gemini surfactant
• monolayer

Acknowledgments

B. K. Mishra thanks Board of Researchers in Nuclear Sciences, BARC, Mumbai, for financial assistance through a research project.