Structural Characterization of Thermally Stabilized Poly(acrylonitrile) Fibers by Means of X-ray Diffraction, FT-IR Spectroscopy, and TGA Analysis


  • TUBA DEMIREL Erciyes University
  • Md. Mahbubor Rahman Bangladesh University of Textiles, Tejgaon, Dhaka, Bangladesh
  • Ismail KARACAN Erciyes University



Stabilized PAN Fibers, Thermal Stabilization, Ammonium Bromide (NH4Br) salts, XRD, FT-IR, TGA.


The structure and effects of thermally stabilized PAN original fibers were characterized utilizing a mixture of volume density, color change observations, flame tests, X-ray diffraction (XRD), infrared spectroscopy (FT-IR), and thermogravimetric analysis (TGA) measurements. The results obtained from the analysis of XRD work showed the conversion of the original molecular structure from a highly laterally ordered condition to a disordered amorphous structure. The experimental results acquired from FT-IR analysis indicated rapid and concurrent aromatization and dehydrogenation reactions assisted by the formation of oxygen-containing functional groups. TGA analysis showed a carbon yield of 72% at 1000 °C. The application and use of NH4Br pretreatment are expected to increase the productivity of carbon fiber processing at lowered cost by significantly reducing the processing time necessary for the successful completion of thermal stabilization reactions.


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How to Cite

DEMIREL, T., Rahman, M. M., & KARACAN, I. (2021). Structural Characterization of Thermally Stabilized Poly(acrylonitrile) Fibers by Means of X-ray Diffraction, FT-IR Spectroscopy, and TGA Analysis. ICONTECH INTERNATIONAL JOURNAL, 5(2), 1–9.