Crosslinking and carbonization processes in PAN films and nanofibers

In all thermal treatments a new IR signal around 800 cm−1appeared, which was attributed to substituted triazine rings formed in the trimerization of nitrile groups of different chains. The data supports the hypothesis of crosslink of the fibers at the beginning of the thermal conversion. The infrared and Raman spectra at 800 °C confirm the carbonization process on the nanofibers.