Influence of Curing Catalyst on the Properties of Reactive Hot Melt Adhesive

Abstract

We have been developing reactive hot melt adhesives (PUR) for fine parts such as displays in smartphones and tablets. The cure time of PUR is important because it needs to be adjusted for each product. In this report, the influences of the type and amount of curing catalyst on the curing time and properties of PUR were investigated. As a result, the elastic modulus of PUR became higher as the amount of catalyst increased. And, it was found that the size of dispersed-phase droplets in the continuous phase was different, depending on the amount of catalyst. PUR tended to be compatibilized as the amount of catalyst increased. We revealed that the difference in microscopic properties between the dispersed phase and the continuous phase made the difference in the macroscopic properties of PUR with different morphology.