Surfactants are mainly used as mixtures to obtain the foam properties which are suitable for use and purpose. In this study, it was found that a mixture of glycinate- and glutamate-based surfactants produced a relatively rigid foam compared to that of single component only when the mixture was diluted with tap water and not deionized water. When the surfactant mixtures were diluted with deionized water, the foam hardness was linearly dependent on the weight fraction of the glycinate based surfactant. Meanwhile, the mixtures diluted with tap water produced foam which could withstand vertical loads. We observed the rheological behavior of the air-water interface to understand the ideal and nonideal mixing effect of amino acid-based surfactants. It was confirmed that the synergistic effect on the interfacial modulus and the foam texture was due to the divalent ions of tap water. However, the interaction by the divalent ions did not affect the foam stability. It is worth to noting that the existence of divalent ions is one of the important factors that should be considered to control the foam quality as well as interfacial rheology.

表面活性剂主要作为混合物使用，以获得适合用途和目的的泡沫特性。在这项研究中，发现甘氨酸盐和谷氨酸盐基表面活性剂的混合物仅在混合物用自来水而不是去离子水稀释时，与单一组分的混合物相比，会产生相对坚硬的泡沫。当表面活性剂混合物用去离子水稀释时，泡沫硬度线性依赖于基于甘氨酸盐的表面活性剂的重量分数。同时，用自来水稀释的混合物会产生可以承受垂直载荷的泡沫。我们观察了空气-水界面的流变行为，以了解基于氨基酸的表面活性剂的理想和非理想混合效果。证实对界面模量和泡沫质地的协同作用是由于自来水的二价离子。然而，二价离子的相互作用不影响泡沫稳定性。值得注意的是，二价离子的存在是控制泡沫质量以及界面流变学的重要因素之一。