Effects of mixing di- and tri-functional epoxy monomers on epoxy/thermoplastic blends

Two different epoxy monomers, based on the diglycidylether of bisphenol A (DGEBA) and triglycidyl-p-aminophenol (TGAP), which are di- and tri-functional, respectively, were mixed in varying proportions and cured with bis(2,6-diethylaniline) (MDEA). Toughened epoxy resins were prepared by adding a coPolyethersulfone (coPES) to the resin mixture. The dynamic mechanical and morphological properties of the cured materials were measured. It was found that the blends based on TGAP presented different viscoelastic and morphological behavior compared to DGEBA-based formulations. Mixing TGAP with DGEBA resulted in increased glass transition temperature and homogeneous phase morphology distribution.