Curing Epoxy Adhesives with Dicyandiamide

This article first offers an introduction to the two main types of epoxy curing mechanisms. It then describes the characteristics and properties of dicyandiamide and how this material achieves crosslinking with epoxy resins. The article then goes further to describe how dicyandiamide is incorporated into epoxy adhesive formulations. Several starting formulations and resulting application and performance properties are also provided. Epoxy technology gives the formulator an almost unlimited number of tools to employ. The type of epoxy polymer backbone, curative, resinous modifiers, and special additives or fillers all serve as degrees of freedom available in developing an adhesive system for a given application. One of the most important parameters and starting-points for formulation development is the selection of the type of epoxy cure mechanism and the specific curing agent that will be used.