离子Gemini表面活性剂在固-液 界面吸附的Monte Carlo 模拟

利用Monte Carlo方法对非离子Gemini表面活性剂在固-液界面的吸附进行了模拟，得到了吸附层厚度、吸附量和链节密度分布，并用两阶段吸附模型拟合了吸附等温线。同时，对Gemini表面活性剂和传统表面活性剂在界面的竞争吸附进行了模拟。结果表明：随着对比温度的升高，单一非离子Gemini表面活性剂在疏水性界面的吸附层厚度减小，吸附量降低，吸附等温线符合两阶段吸附模型。在相同能量参数下，Gemini表面活性剂在界面吸附的能力远比传统表面活性剂在界面吸附的能力强，它可将表面上已吸附的传统表面活性剂解吸下来，从而影响界面性质。

Monte Carlo Simulation on Adsorption of Nonionic Gemini Surfactant at Solid-Liquid Interfaces

The adsorption of nonionic Gemini surfactant at solid-liquid interfaces was studied by Monte Carlo simulation. The thickness of adsorption layer, the amount of adsorption, and the segment density distribution were obtained, and adsorption isotherms were fitted using two step adsorption model. In addition, simulation of competitive adsorption was studied using Gemini surfactant and traditional surfactant. Results show that at hydrophobic interfaces the thickness of adsorption layer decreases, adsorption amount declines with the increase of temperature, and the adsorption isotherm fits two-step adsorption model well. The adsorption ability of Gemini is better than that of traditional surfactant at the same energy parameters, and Gemini can replace traditional surfactant from the surface and thus influences the property of interface.