Ternary blends in the toughening of epoxy resins

Abstract
The fracture properties of two types of ternary blends (amine terminated rubber/Bisphenol‐A/DGEBA resin) have been studied. In the first type, B, setting was obtained by using piperidine as the hardener. In the second type, C, the rubber was used as both the hardener and the toughener. Both types showed an increased fracture resistance over the binary rubber/resin formulations. The drawback of the too high reaction rate shown by type B blends can be eliminated by using type C blends which can be easily B‐staged.