Effects of network structure on the interfacial adhesion between epoxy composites and copper foil

The relationships between the epoxy conversion, the glass transition temperature, and the peel strength (or failure energy) for three epoxy resin prepregs were investigated. Composites were fabricated by laminating prepreg between two sheets of oxide-treated copper foil. The lamination process was aborted at various time increments, and the laminates were quickly cooled. For each sample, the conversion and the glass transition temperature were measured with differential scanning calorimetry. The failure energies were determined using a 90° peel test. Scanning electron microscopy was used to examine the failure surfaces after the peel test.