Capillary Bonding of Membranes by Viscous Polymers: Infiltration Kinetics and Mechanical Integrity of the Bonded Polymer/Membrane Structures

Capillary infiltration of porous medium impacts applications across oil recovery 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 talk, we present capillary infiltration study of a viscous polypropylene (PP) within polyethersulfone (PES) membranes. The infiltration kinetics was determined under varying infiltration temperature, membrane chemistry and pore structure (pore size and degree of asymmetry). The experimental data was better described by models such as the Cai model that incorporates membrane pore structures, compared with the basic Lucas Washburn model commonly used for isolated cylindrical pores. The mechanical integrity of the bonded PP/membrane structures was further evaluated with a modified T-peel test, displaying a range of debonding or failure behaviors that are dependent on the pore size and infiltration depth.