Characterization of an ABS‐modified epoxy system

In this work an epoxy system containing a diglycidyl ether of bisphenol A (DGEBA) and 1,3‐bis(aminomethyl)cyclohexane (1,3‐BAC) is modified with poly(acrylonitrile‐co‐butadiene‐co‐styrene) (ABS). Using dynamic mechanical analysis the glass transition temperatures and the associated activation energies are determined in the neat epoxy and some blends. The presence of ABS produces a constant diminution of the glass transition temperatures and increases the activation energies. The brittle character of the neat epoxy and the blends, compared with the ductile character of ABS, is studied using an instrumented impact pendulum. The shape of force–time curves and energies and data dispersion of each composition are analyzed. By using scanning electron microscopy it is possible to see various zones of different roughness and to distinguish the regions of tension and compression of Charpy impact fractured surfaces. The presence of a two phase‐morphology in the epoxy‐ABS blends is also shown.