Carbonization performance of pre-oxidized PAN fibers prepared by microwave heating

We have carbonized the modified PAN fibers which coated with a hybrid microwave absorbent and pre-oxidized by microwave heating for 50 min. The carbonization process of pre-oxidized CB/S-PAN fibers process was performed under nitrogen atmosphere at different temperatures. The carbonized fibers were characterized by mean of Raman spectroscopy, elemental analyzer, X-ray diffraction (XRD), thermogravimetric analyzer (TGA), mechanical tester, and scanning electron microscopy (SEM). The results indicated that more ordered crystal structure and highly graphitic content was obtained at 950ºC, arise from the formation of aromatic structures. The fibers’ surface appeared roughly without defects suggesting a strong graphitic structure. This rough nature which results from the deposition of nanoparticles at an earlier stage before the pre-oxidation and the microwave penetration can strongly improve the interlocking between the fibers and matrix in the carbon fibers’ composites.