Study on the deterioration of an epoxy-type adhesive containing nitrile rubber

Abstract

The mechanism of the deterioration process of an adhesive composed of nitrile rubber(NBR) and epoxy resin is discussed based on the techniques of differential scanning calorimetry (DSC), transmission electron microscope (TEM), FT-IR and GC. An accelerated test of the adhesive was carried out at 120 °C and 100% relative humidity. It was found that the deterioration of the adhesive was mainly due to degradation of the NBR domain. The glass transition temperature of the adhesive became lower and the staining ability of OsO1 for the NBR decreased with time. The degradation of the NBR was accelerated by decrease in the antioxidant content during curing step of the adhesive.