Adhesive

A substance (like glue) that is used to join two substances. An adhesive must bond both mating surfaces through specific adhesion (molecular attraction), through mechanical anchoring (by flowing into holes in porous surfaces), or through fusion (partial solution of both surfaces in the adhesive or its solvent vehicle). Various descriptive adjectives are used with the term adhesive to indicate types, such as a. physical form Liquid adhesive, film adhesive, etc. b. composition Resin adhesive, rubber adhesive, silicone based, mastic, etc. c. end use Metal-to-metal adhesive, plastic adhesive, rubber adhesive d. application Sprayable adhesive, hot melt adhesive, etc. Agent for joining materials by adhesion, usually polymeric material. May be based on thermoplastic resin (e.g., polystyrene cement) or thermoset (e.g., epoxy resin). Viscosity is important for gap filling (high, as in epoxies) or surface penetration (low, as in cyano-acrylates). Also called binder, cement, or glue