Effects of carbon black and graphene nano-platelet fillers on the mechanical properties of syntactic foam

Mechanical properties of an epoxy based syntactic foams are discussed in this study. Basic syntactic foam, composed of 30% of hollow glass spheres by volume, was modified with a 1% volume fraction addition of graphene nano-platelets (GnP), treated GnPs and carbon black (CB). In treated GnPs the hollow glass spheres and the GnPs were treated with 1-Pyrenecarboxaldehyde in xylene. The flexural, tensile, compressive and Izod properties of the five different combinations of these syntactic foams, both reinforced and not reinforced, were measured and compared with the pristine epoxy. The tests show that the reinforced foams had a higher modulus in all cases. The maximum tensile load decreased with the addition of the GnPs, while it increased when CBs were used. Scanning electron micrographs were used to evaluate the dispersion of the filler in the epoxy matrix and the interaction between matrix and fillers.