2 - Introduction to Surface Preparation and Adhesion

Abstract

This chapter discusses the definitions of surface preparation, adhesives, and adhesives bonding. Surface preparation or treatment is defined as one or a series of operations including cleaning, removal of loose material, and physical and/or chemical modification of a surface to which an adhesive is applied for the purpose of bonding. The main reasons for applying surface treatments prior to bonding are removing or preventing the later formation of a weak layer on the surface of the substrate, optimizing the adhesion forces, and creating specific surface microstructure on the substrate. An adhesive is a material that is applied to the surfaces of articles to permanently join the articles by a bonding process. The material is capable of forming bonds to each of the two or more parts of which the final object consists. Adhesion, on the other hand, refers to the state in which two dissimilar bodies are held together by intimate interfacial contact such that mechanical force or work can be transferred across the interface. There is unifying theory of adhesion that relates the physical-chemical properties of materials to the actual physical strength of an adhesive bond. The interfacial forces holding the two phases together may arise from van der Waals forces, chemical bonding, or electrostatic attraction.