Pepin X, Rossetti D, Simons SJ
Colloid and Surface Engineering Group, Department of Chemical Engineering, University College London, Torrington Place, London, WC1 7JE, UK
J Colloid Interface Sci. 2000 Dec 15;232(2):298-302. doi: 10.1006/jcis.2000.7183.
Liquid bridges formed between particles of dissimilar surface properties are important in many processes involving the handling of powders in mixtures. For instance, growth kinetic models for wet granulation frequently incorporate the evolution and resistance to breakage of individual liquid bridges between particles in a statistical form. These models generally propose a confusing definition of liquid-to-solid contact angles. Taken as a single thermodynamic value, they typically neglect the influence of wetting hysteresis on the liquid bridge. In this paper, a simple model based on the interfacial energies is proposed for the evolution of liquid bridges when one solid-liquid interface reduces. This receding process is well described by a balance between the adhesion energy of the bridge liquid on the particle surface and the capillary energy stored by the liquid free surface. The extent of solid-liquid interfacial area reduction can hence be predicted from the initial liquid bridge configuration. The liquid bridge shape is approximated by a parabolic curve, which is validated from the good agreement between measured and calculated contact angles or liquid-vapor interfacial area. Copyright 2000 Academic Press.
在许多涉及混合粉末处理的过程中，具有不同表面性质的颗粒之间形成的液桥非常重要。例如，湿法制粒的生长动力学模型通常以统计形式纳入颗粒间单个液桥的演变和抗破裂性。这些模型通常对液 - 固接触角给出令人困惑的定义。作为单一的热力学值，它们通常忽略了润湿滞后对液桥的影响。本文针对一个固 - 液界面减少时液桥的演变提出了一个基于界面能的简单模型。这个后退过程可以通过桥接液体在颗粒表面的粘附能与液体自由表面储存的毛细管能之间的平衡很好地描述。因此，可以根据初始液桥构型预测固 - 液界面面积减少的程度。液桥形状用抛物线曲线近似，这通过测量和计算的接触角或液 - 气界面面积之间的良好一致性得到验证。版权所有2000年学术出版社。
