Carbon Based Nanostructures Hybrids for Composites Materials: The Graphene—Carbon Nanotubes Interaction Investigation

Abstract

Two different carbon based nanostructures, multiwall carbon nanotubes and multilayeredgraphene, were incorporated to carbon epoxy laminates. X-ray diffractometryindicates an average particle size of 22 nm for the multi-layer graphene (MLG) nanostructures.TEM observations revealed a thickness of 10 graphene layers, and a hybridnanostructure where MWNT interpenetrated the MLG nanostructure. To be ableto disperse more efficiently the carbon based nanostructures two different surfactantswere employed, i.e. Sodium dodecylbenzenesulfonate (SDBS) and Polyoxyethylenenonylphenyl ether (IGEPAL CO890). The dispersion of surfactants associated to grapheneled to increase on stiffness and strength, for both tensile and bending loads.If on the top of these surfactants/graphene additions, CNTs are added, the improvementis even better. For tensile tests, the average peak stress increase from 542.76MPa (blank specimen) to 667.51 MPa (CO 890 and graphene/CNT), while for bendingthe peak stress improved from 369.40 MPa (blank specimen) to 584.15 MPa (CO 890and graphene/CNT). The association of carbon based nanostructures (graphene andCNT) associated to surfactants seems to be a promising route to improve carbon/epoxycomposites. Finally, the addition of carbon based nanostructures increased the hybridcomposites toughness between 39.59% (from 4.712 to 6. 578 J/m3 x 104) and 180.65%(from 4.712 to 13. 225 J/m3 x 104).