Compression-induced graphite nanoplatelets orientation in fibre-reinforced plastic composites

We demonstrate a facile and general technique for the orientation of nanoplatelet fillers dispersed in adhesives for tensile strength enhancement of compressed fibre-reinforced plastic (FRP) composites. Polyurethane adhesives filled with a selected exfoliated graphite nanoplatelet (MexGnP-8) powder at concentration range of 0-0.75 wt% were prepared. The same adhesives were used to fabricate compressed FRP composites in which the mechanical properties were assessed and found to be inconsistent with the findings from the tests conducted on uncompressed FRP composites and the filled adhesives. Only the polyurethane adhesive filled with 0.25 wt% MexGnP-8 had tensile strength higher than that of the neat adhesive, and the uncompressed FRP composites have similar results. However, all the compressed FRP composites fabricated with the polyurethane adhesive filled with MexGnP-8 between the concentration range of 0-0.75 wt% had greater tensile strengths than the compressed FRP fabricated with the neat adhesive. Compression has been found to induce orientation of MexGnP-8 and resulted in tensile strength enhancement in the FRP.