Castellanos Aly J, Toro-Mendoza Jhoan, Garcia-Sucre Maximo
Laboratorio de Fisicoquimica de Coloides, Centro de Fisica, Instituto Venezolano de Investigaciones Cientificas (IVIC), Carretera Panamericana, Km. 11, Altos de Pipe, Caracas 1020A, Venezuela.
J Phys Chem B. 2009 Apr 30;113(17):5891-6. doi: 10.1021/jp808906p.
In this work we analyze the behavior of the interfacial tension with the curvature radius of the disperse phase. Following the Young-Laplace deduction of the equation relating the internal pressure with the curvature radius for a fluid confined by a spherical interface, we restate the Tolman approach [J. Chem. Phys. 1949, 108, 333] to obtain an analytical expression relating the interfacial tension with the radius. We have found small differences between our results and those of Tolman for the liquid/gas (droplets) case. However, important differences between liquid/gas (droplets) and gas/liquid (bubbles) dispersions were found. In particular, the decrease in the interfacial tension of bubbles may be expected to occur for much larger curvature radii than for the case of droplets when the curvature radius decreases. A simple relation between the Tolman's delta parameter and the interfacial width is also discussed. In our calculations we have considered dispersions of droplet of water in methane and bubbles of methane in water at T = 273.15 K.
在这项工作中，我们分析了界面张力随分散相曲率半径的变化行为。遵循杨氏-拉普拉斯推导的关于由球形界面限制的流体的内压与曲率半径之间关系的方程，我们重新阐述了托尔曼方法[《化学物理杂志》1949年，第108卷，第333页]，以获得一个将界面张力与半径相关联的解析表达式。我们发现，在液/气（液滴）情况下，我们的结果与托尔曼的结果存在细微差异。然而，发现液/气（液滴）和气/液（气泡）分散体系之间存在重要差异。特别是，当曲率半径减小时，气泡界面张力的降低预计会在比液滴情况大得多的曲率半径下发生。还讨论了托尔曼δ参数与界面宽度之间的简单关系。在我们的计算中，我们考虑了在T = 273.15 K时，甲烷中水滴的分散体系和水中甲烷气泡的分散体系。
