Preparation and characterization of isotropic pitch-based carbon fiber

Abstract

Isotropic pitch fibers were stabilized and carbonized for preparing carbon fibers. To optimize the duration and temperature during the stabilization process, a thermogravimetric analysis was conducted. Stabilized fibers were carbonized at 1000, 1500, and <TEX>$2000^{\circ}C$</TEX> in a furnace under a nitrogen atmosphere. An elemental analysis confirmed that the carbon content increased with an increase in the carbonization temperature. Although short graphitic-like layers were observed with carbon fibers heat-treated at 1500 and <TEX>$2000^{\circ}C$</TEX>, Raman spectroscopy and X-ray diffraction revealed no significant effect of the carbonization temperature on the crystalline structure of the carbon fibers, indicating the limit of developing an ordered structure of isotropic pitch-based carbon fibers. The electrical conductivity of the carbonized fiber reached <TEX>$3.9{\times}10^4$</TEX> S/m with the carbonization temperature increasing to <TEX>$2000^{\circ}C$</TEX> using a four-point method.