Surface Tension and Its Measurement

Surface sciencestudies the behavior and characteristics of molecules at or near a surface or interface. The interface can be between solids, liquids, gases, or combinations of these states. Complex apparatus is used to identify and quantify surfaces and interfaces. Polymer surfaces are of special interest in industrial and biological applications, e.g., dental implants and body part prosthetic devices. Modification of the surfaces of these devices allows formation of controlled interfaces to achieve characteristics such as bondability and compatibility.Adhesion is an interfacial phenomenon that occurs at the interfaces of adherends and adhesives. Thisfact underlies the macroscopic process of joining parts using adhesives. An understanding of the forces that develop at interfaces is helpful in selecting the right adhesive, proper surface treatment of adherends, and effective and economical processes to form bonds. Surface preparation techniques are partly aimed at changing the surface energy of materials. This chapterdiscusses the thermodynamic principles and work of adhesion that characterize material surfaces.