Influence of Surface-Active Component on the Interfacial Dilational Properties of Asymmetrical Anionic Gemini Surfactant C_(12)CO_2Na-p-C_9SO_3Na

摘要

The influence of two surface-active components, oleic acid and octadecanol, on the interfacial dilational viscoelasticity of an oil-water interfacial layer containing asymmetrical anionic gemini surfac_tant C_(12)COONa-p-C_9SO_3Na has been investigated. The results show that surface-active component concentration is an important factor in controlling the dilational properties of mixed-adsorption layer. A small quantity of surface-active component may enhance the dilational modulus by forming densely packed mixed-adsorption layer through hydrophobic interaction, while the superfluous addition of surface-active components could sharply decrease the dilational modulus mainly due to the weakening of the crosslink and entanglement among long alkyl chains in surfactant molecules.