Interfacial free energies high-energy surfaces

In the systems we have used for 3D MESA, the capillary forces act through thin liquid films that coat the faces of the objects [refs. 6, 15]. These films possess a high interfacial free energy in contact with water. When two surfaces... 

In dishwashing, one must consider soil and surfactant adsorption to both polar and nonpolar surfaces. Metals (aluminum, stainless steel, carbon steel, cast iron, silver, and tin), siliceous surfaces (china, glass, and pottery), and organics (polyethylene, polypropylene, polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), and wood) present a wide variety of surface characteristics. They span the range of high interfacial free energy (metals and many ceramics) to low interfacial free energy (hydrocarbon polymers) surfaces [27,28],... 

Equation (645) shows that contact angle is a thermodynamic quantity, which can be related to the work of adhesion and interfacial free energy terms. When 6 values are small, the work of adhesion is high and considerable energy must be spent to separate the solid from the liquid. If 0 = 0°, then W L = 2yv if 0 = 90°, then W L = yLV, and if 0 = 180°, then W1L = 0, which means that no work needs to be done to separate a completely spherical mercury drop from a solid surface (or a water drop from a superhydrophobic polymer surface), and indeed these drops roll down very easily even with a 1° inclination angle of the flat substrate. 

Surfaces adsorbing a minimal amount of protein are important in many applications such as blood-contacting devices, membrane separators, sensors, and contact lenses. Therefore, much effort has been expended on minimizing or eliminating protein adsorption. To prevent protein adsorption, the utilization of water-solnble polymers such as polyacrylamide, poly(A -vinyl-2-pyrrohdone), and PEO has been considered. In particular, PEO has a low interfacial free energy with water, unique solution properties, molecular conformation in aqueous solution, high surface mobility, and steric stabilization effects [38,39] (Figure 11.5). 

Previous attempts to measure the interfacial free energy at the cell surface have also used the contact angle technique. Harvey placed oil droplets inside cells, but found the contact angle to be very high and had to place the cells in a centrifugal field to obtain meaningful measurements. He concluded that the cell-medium interfacial free energy was less than 1 erg/cm but could not obtain a precise value. Van Oss, measured... 

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