The addition of surfactants to modify the surface property of nanoparticles (NPs) from hydrophilic to hydrophobic also enhances their interfacial properties. Several approaches were previously proposed to calculate the surface tension/interfacial tension (IFT) for different systems in the presence of NPs, surfactants, and electrolytes. However, most of these approaches are indirect and require several measured parameters. Therefore, a mathematical model is developed here to calculate the surface tension/IFT for these systems. The developed model takes into account the cohesive energy due to the interaction of the surfactant CH₂ groups, the electric double layer effect due to the interaction among the ions of NPs, surfactants, and electrolytes, and the dipole–dipole interaction of NPs and electrolytes. The developed model is compared and validated with the laboratory experimental data in literature. The results reveal further understanding of the mechanisms involved in stabilization of oil/water emulsion in the presence of NPs, surfactants, and electrolytes.

中文翻译：

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纳米粒子，表面活性剂和电解质溶液的界面能

添加表面活性剂以将纳米颗粒（NPs）的表面性能从亲水性改变为疏水性也可以增强其界面性能。先前提出了几种方法来计算在存在NP，表面活性剂和电解质的情况下不同系统的表面张力/界面张力（IFT）。但是，这些方法大多数都是间接的，需要几个测量的参数。因此，这里开发了一个数学模型来计算这些系统的表面张力/ IFT。所开发的模型考虑了由于表面活性剂CH ₂相互作用而产生的内聚能在基团中，由于NP离子，表面活性剂和电解质之间的相互作用以及NP和电解质的偶极-偶极相互作用而引起的双电层效应。将开发的模型与文献中的实验室实验数据进行比较和验证。结果揭示了对在NP，表面活性剂和电解质存在下油/水乳液稳定化机理的进一步理解。