• hyperbranched;
  • epoxy;
  • blends;
  • morphology;
  • thermomechanical properties


The thermomechanical and morphological properties of some epoxy blends modified with hyperbranched polymers are reported. The effects of pseudo-generation numbers, from the second to the fourth, were studied. All the hyperbranched polymers used had [BOND]OH end groups. The blends were thoroughly characterized in both the unreacted and cured states. The unreacted blends, characterized by parallel plate rheometry and hot stage microscopy, revealed that pseudo-generation number can have a profound effect both on the reactivity and the phase separation behavior. Analysis of the cured samples was carried out through scanning electron microscopy, dynamic mechanical tests, and fracture mechanics. The results supported some findings obtained from the analysis of the unreacted blends; and dynamic mechanical analysis helped shed more light on the phase separation behavior. Pseudo-generation number also influenced the glass transitions of the blends. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010