An in-depth study of the adsorption and micellization behavior of a series of fatty amide ethoxylates is presented. The effect of the amide bond is studied as well as variations in unsaturations in the hydrocarbon chain and in the length of the oxyethylene headgroup. Ellipsometry is used to determine adsorption on a hydrophobic silica plate while 1H-NMR self-diffusion is used to study micelle size and structure. The amide bond was found to increase the hydrophilicity of the surfactant leading to less-favorable packing at the interface. The micelles formed by these surfactants were more compact, compared to alcohol ethoxylates with the same hydrophobe. Effects of unsaturations on the interfacial packing were not observed. The micelle structure was somewhat affected by the unsaturations due to increased bulkiness of the surfactant hydrophobe.
- H-NMR self-diffusion
- Double bonds
- Fatty acid monoethanolamide ethoxylate
- Interfacial adsorption