Epoxy resins as one of the most important thermoset materials have shown various
applications in production of composites, adhesives and surface coatings. Due to
formation of the network structure, the cured epoxy resin shows brittleness and low impact
resistance. The mechanical properties in the epoxy resin (especially the fracture toughness)
can be modified by adding a softer phase preferably the rubber phase, thermoplastic fillers
and even rigid particles. In comparison with other methods, the inclusion of rigid particles
into epoxy resin improved the fracture toughness of epoxy resin without sacrificing the
other main properties of epoxy resin such as the modulus (E) and glass transmission
temperature (Tg). In recent years, the introduction of nanotechnology has shown some
possibilities in toughening improvement of nanomaterials. Due to the special properties
and different types of nanoparticles, a review study on effective nanoparticles would be
useful in utilizing nanomaterials in toughening of the epoxy resin