The study of the graphitization behavior for polyimide and polyamide films

The structure transformation for the carbonized polyimide and polyamide films during their resistance heat-treatments has been examined. Two polymer precursor films, Kapton (here after Kp) (polyimide polymer) film, and Mk (polyamide polymer) film, were carbonized to 900°C under Ar in furnace. A direct resistance heating approach, a DC current passed through the film via electrodes, was utilized for the further heat-treatment of these carbonized polymer films under inert atmosphere. The heating processes were carried out by step increasing either the supply voltage, or the supply current to their destined values. The processed films have been characterized by X-ray diffraction (XRD), Raman, SEM, and four probes conductivity measurement. The results of XRD seem to suggest an earlier d-spacing dropping for the carbonized Kp films from 1400 to 1600°C under the resistance heating process. The carbonized Mk film gives a different XRD pattern than the Kaptonʹs during its heat-treatment process.