XPS Investigation into Thermal Degradation and Stabilization of Polyacrylonitrile Fibers

摘要

PAN copolymer fibers have been heated in air to different HTT from 190 to 270℃. The functionalities of the C, O and N in the precursors were determined by X-ray photoelectron spectroscopy (XPS). The intensity of Cls spectra line 286.8ev which is identified as C-O and C=N functionalities has been found to initially increase, and suddenly decrease above 230℃. Additionally, the significant broadening of Nls spectra line has also been observed at the same HTT. It is suggested that some oxygen has been incorporated to the six-member heterocyclic structures that formed by cyclization of nitrile groups, and transformed into pyridone structures by elimination of carbon monoxide.