Phase separation in anhydride-cured epoxy resin containing phenolphthalein poly(ether ether ketone)

Dynamic mechanical analysis and scanning electron microscopy were used to study phase separation of three blends of anhydride-cure bisphenol-A-type epoxy resin with phenolphthalein poly(ether ether ketone). Phase separation was observed for all the blends. The overall compatibility and the resulting morphology of the cured blends are dependent on the choice of cure agent. The phenomena have been discussed from the points of view of both thermodynamics and kinetics. The effects of the choice of hardener on phase separation are considered to be primarily due to differences between the chemical natures of the hardeners.