Investigation of the Microstructure of Epoxy Resin/MWNTs Nanocomposite by the Positron Annihilation Technique

Diethylenetriamine (DETA) was non-covalently wrapped onto the surface of multi-walled carbon nanotubes (MWNTs). The surface properties of MWNTs were investigated by Fourier transform-infrared spectra (FTIR) and X-ray diffraction (XRD). Influence of MWNTs content on the free volume of epoxy/MWNTs nanocomposites was investigated by positron annihilation lifetime spectroscopy (PALS). As a result, the amine group was successfully wrapped onto the surface of MWNTs. For the nanocomposites, the free volume concentration decreased, while its size increased with the increasing MWNT content. And the impact strength was enhanced up to 100% when MWNTs-20%NH(2) content was 0.6 wt%.