中文摘要：

铺展液膜与预置液膜间的分离压效应是影响铺展或去湿过程的重要因素之一。基于表面活性剂特性对引力和斥力的不同影响,建立了分离压和自由能密度理论模型,导出了最小分离压和最小自由能密度及相应液膜厚度比的理论关系式,分析了斥力与引力比F、分离压和自由能与活性剂浓度、液膜厚度比间的变化关系。研究表明,随表面活性剂浓度的提高,F整体呈增大趋势;分离压和自由能密度在液膜厚度比h/h∞〈1和h/h∞〉1呈单驼峰和倒驼峰型变化;当液膜厚度比不同时,存在分离压和结合压两种情形,最小分离压和自由能密度在h/h∞奇点前后呈现截然不同的变化,奇点位置与（n,m）的取值有关。

英文摘要：

The disjoining pressure between spreading films and precursor films is one of most important factors in dominating the spreading and dewetting of surfaetant solutions. Considering the different impacts of surfactant concentration on repulsive and attractive forces, the models of disjoining pressure and free energy density are established, and the theoretical relations of minimum disjoining pressure, free energy density and corresponding film thickness ratio are formulated. The present paper investigates the trends of the ratio of repulsive to attractive force F, disjoining pressure and free energy density with surfaetant concentration and film thickness ratio h/hm. Investigation shows that the ratio F increases with surfactant concentration, and the disjoining pressure and free energy density present a single hump trend under h/hm 〈 1 and a reverse hump h/hm 〉 1. The disjoining pressure and conjoining pressure will occur under different film thickness ratio. The minimum disjoining pressure and free energy density illustrate totally different trends around singular point of film thickness ratio, which is closely related with the index m and n.