5. Characteristics of glues and adhesives

5.1 Pick-up mode

In all cases, an adhesive or glue is a product :

• which is initially pasty or liquid, enabling it to be spread over the materials to be joined. The adhesive must then bond to these materials (adhesion phenomenon (figure 6 ), requiring the substrates to be properly wetted);

• then, at some point, hardens to ensure a solid, mechanically resistant bond between the two materials (glue setting, or hardening, or drying, as the case may be). The glue is said to develop cohesion.

The way glues and adhesives set depends on their chemical and physical nature. Several systems...