Fracture mechanisms of epoxy filled with ozone functionalized multi-wall carbon nanotubes

This work focused on the fracture mechanisms and reinforcing effects of ozone-treated multi-walled carbon nanotubes (MWCNTs) in epoxy matrix. Ozone functionalization of MWCNTs was found to be of help for a better dispersion and stronger interfacial bonding with epoxy matrix, which in turn improve the strength and fracture toughness of the resin. The MWCNT/epoxy composites showed complicated failure modes than the conventional fibrous composites, which have been quantitatively investigated and correlated with the fracture toughness of the nanocomposites studied.

► We focused on the reinforcing effects of ozone-treated carbon nanotubes in epoxy.
► Nanotubes perform better dispersion and stronger interfacial bonding with matrix.
► The mechanical properties of nanocomposites were significantly improved.
► The nanotube failure modes transferred from pullout to sliding-fracture.
► This failure mode favors the energy absorption and contributes to improved toughness.