Fillers Segregation on the Surface of Epoxy Resin Composites

Glass microfillers shallow segregation in epoxy resins composities was investigated. The presence of such fillers at the interface of epoxy resins has important consequences on the surface properties of these materials as in the case of conductive resins, fiberglass hulls, screens ablative, non-slip surfaces, floorings, adhesives and coatings in general. The effects of two microfillers parametres were investigated: the density, comparing the distribution in the cured resin of hollow microspheres with that of filled spheres, and the wettability, by treating the beads with 3-aminopropyl-trimethoxy-silane to ensure good adhesion to the matrix and octadecyl-trimethoxy-silane, which, instead, makes them incompatible with it. The morphology of these specimens was investigated by scanning electron microscopy (SEM). The chemical characterization of the microparticles, and the loaded resin was performed by FT-IR / ATR and by X-ray spectroscopy (EDS), the latter has been especially useful for surface mapping. It was found that the combined effects of a low density with a poor adhesion to the matrix help beads to segregate at the surface