Chromatographie

As nearly all polymers cured adhesives also contain some low-molecular-weight substances. On the one hand there are unchanged components of the adhesive mixture such as curing agents, accelerators, plasticizers or resins. On the other hand there are also a lot of unknown byproducts of the curing reaction. Because of their possibility to diffuse these substances can have an effect on the adhesive joint, especially after influence of humidity. In order to characterize the low-molecular-weight compounds it is necessary to separate the different substances from each other. Gaschromatography (GC), High-Performance-Liquid-Chromatography (HPLC) and Size-Exclusion-Chromatography (SEC) are successfully used for this problem of separation. A short survey is given to show some applications of the different chromatographic methods and investigations with well defined adhesives and epoxy-resins are presented which describe the curing behaviour of epoxy-adhesives on alumina