The effect of carbonization temperature of PAN fiber on the properties of activated carbon fiber composites

Abstract

The PAN (polyacrylonitrile) based carbon fiber composites were prepared from mixtures of chopped carbon fibers and phenolic resin. Two different carbon fibers were obtained by carbonization of stabilized PAN fiber precursors in nitrogen at 1073 and 1273 K, respectively. Samples of activated carbon fiber composites (ACFCs) were prepared from the carbon fiber composites by activation in carbon dioxide at 1123 K for 10–90 minutes. The effect of carbonization temperature of a precursor fiber on the specific surface area and the bending strength of ACFCs were studied in this work. As the burn-off of ACFC made of the fiber carbonized at 1073 K was increased from 37 to 75%, the specific surface area increased from 500 to 1100 m 2 g −1, and the bending strength decreased from 3.6 to 1.8 MPa. These values were about two times larger than those made of the fiber carbonized at 1273 K. The effect of carbonization temperature of a precursor fiber on the bending strength of ACFC was ascribed to the bonding strength between the carbonized fiber and phenolic resin binder, and to the density of the ACFC.