Capillary infiltration of porous medium impacts applications across oil recovery, soil science, and hydrology. The infiltration kinetics is typically captured by a range of models that differ in the approximation of pore structures, fluid properties, and filling ratio. Capillary bonding of a porous membrane by a polymer melt is important for membrane device manufacturing. However, both the capillary infiltration kinetics and the resulting bonding strength or mechanical integrity have not been reported. In this work, we measure the kinetics of capillary infiltration of a viscous polypropylene (PP) in polyethersulfone (PES) membranes with a normal pore size of 200 nm and varying degrees of hydrophilicity. The time-dependent infiltration depth was quantified ex situ by imaging the cross-sections of the bonded PP film/PES membranes. The microscopic details of the bonded interface were characterized by high-resolution nanomechanical imaging, while the contact angles of PP on the PES surfaces were measured by the sessile droplet method. The results show that the infiltration kinetics at 180 °C is better described by the Cai model that incorporates membrane pore structures (porosity, tortuosity, pore size), compared with the basic Lucas Washburn model intended for isolated cylindrical pores. The infiltration kinetics at 200 °C appears significantly slower than the predictions of both models, which is hypothesized to be a result of pore deformation/collapse due to the capillary pressure when the PES approaches the rubbery state. Regardless of bonding temperature, the resulting mechanical integrity of the bonded PP film/PES membrane, as quantified by a modified T-peel test, is dictated by the fracture strength of the membranes and weakly decreases with the increase of infiltration depth.

多孔介质的毛细管渗透影响了采油、土壤科学和水文学的应用。渗透动力学通常由一系列模型捕获，这些模型在孔隙结构、流体特性和填充率的近似值方面有所不同。聚合物熔体对多孔膜的毛细管结合对于膜装置的制造很重要。然而，毛细管渗透动力学和由此产生的结合强度或机械完整性都没有报道。在这项工作中，我们测量了粘性聚丙烯 (PP) 在具有 200 nm 正常孔径和不同亲水性程度的聚醚砜 (PES) 膜中的毛细管渗透动力学。随时间变化的渗透深度被非原位量化通过对粘合的 PP 膜/PES 膜的横截面进行成像。结合界面的微观细节通过高分辨率纳米力学成像进行表征，而 PES 表面上 PP 的接触角通过固着液滴法测量。结果表明，与用于孤立圆柱孔的基本 Lucas Washburn 模型相比，结合了膜孔结构（孔隙率、弯曲度、孔径）的 Cai 模型更好地描述了 180 °C 下的渗透动力学。200 °C 下的渗透动力学似乎比两种模型的预测都慢，这被假设是 PES 接近橡胶状态时毛细管压力引起的孔隙变形/坍塌的结果。无论粘合温度如何，