Study of the Photo Initiated Curing Process of Transparent Adhesives

Clear, transparent adhesives are of special interest for load-bearing joints in façade technology and glass construction. Glass-metal joints and fully transparent glass frame corners are exemplarily fields of application. Single-component photo initiated curing systems were used to make the production process more efficiently. Until now, there is an apparent lack of knowledge regarding the influence of ambient conditions on the curing process of these adhesives. This paper presents the results of an experimental study performed on several single-component and radical curing acrylate systems as well as on several single-component and cationic curing epoxy resin systems. The analysis comprises the influence of the light source intensity and of the layer thickness on the curing and on the thermo-mechanical properties of these adhesives. Furthermore, a selection of results of various analysis methods to evaluate these effects, including calorimetric, thermo- mechanical and spectroscopic methods is presented.