Fig. 13. Field emission scanning electron microscope images of the cross-sectional fracture of multi-walled carbon nanotube–nylon 6 composites: panel (a) PRC10-II, panel (b) PRC10-I, panel (c) PRCS10 and panel (d) PAC10. For more detailed information about the definitions of these composites, the reader is referred to the relevant literature.²²⁶ It was clearly observed from panel (b) that the carbon nanotubes were broken, as indicated by arrow, which is of great importance to research and develop methods for the preparation of multi-walled carbon nanotube–reinforced polymer composites. It is interesting to note that a belt like carbon nanotube was observed which interconnected polymer lumps, as indicated by arrow in panel (d). This typical phenomenon also indicated that there was a strong interfacial adhesion between the carbon nanotube and the polymer matrix, and a sufficient load transfer from the polymer matrix to the carbon nanotubes. The figure is adapted with permission from ref. 226. Copyright 2009, Elsevier B.V.