On the top is the image of a car stuck to a billboard. The words next to it describe the types of adhesion. Types of adhesion Adhesion can work in three ways. Molecules of the polymer may fill crevices in the surfaces being connected. The molecules may also be attracted to one another by intermolecular forces, or they may react by forming covalent bonds. Permanent adhesion: An epoxy resin was used to attach the automobile to the billboard. Epoxy resins are often stored in two parts that are mixed just before the epoxy is used. Strong binding forces in these adhesives make them heat- and water-resistant. Temporary adhesion: The sticky strip on a reusable note is an adhesive containing tiny spheres. The spheres limit the amount of surface area that makes contact, so the note sticks lightly and repositions easily. Below it is a diagram that describes how liquid adhesives work.

1. Liquid adhesive: In a typical adhesive, monomer molecules and a stabilizer are in a solvent. The stabilizer stops the monomers from forming a solid polymer.
2. Applying the adhesive: Some of the liquid is squeezed onto one of the surfaces to be joined.
3. The adhesive sets: Contact with water in the air and on the surfaces being joined makes the stabilizer inactive. The monomers then begin to join together to form a polymer. As the chain lengthens, the adhesive changes from a liquid to a solid.