Melt processable polyacrylonitrile copolymer precursors for carbon fibers: Rheological, thermal, and mechanical properties

Abstract

Polyacrylonitrile (PAN) copolymers containing varying amounts of methyl acrylate (MA), P(AN-co-MA), were synthesized as a melt-spinnable precursor of carbon fibers. The rheological properties of P(AN-co-MA) with MA content of 15 mol% at 190 degrees C proved to be suitable for melt-spinning and the PAN fiber was spun from an extruder. In order to prevent remelting and fusion of the fibers in the stabilization process, electron-beam irradiation of over 1500 kGy was used and the melt-spun PAN fibers were successfully converted to stabilized PAN fibers by thermal treatment up to 250 degrees C. Finally, carbon fibers (CFs) were produced by pyrolysis of the stabilized PAN fibers. The mechanical properties of the resulting-CFs were evaluated; the tensile strength, tensile modulus, and elongation at break were 1.37 +/- 0.2 GPa, 110 +/- 11.1 GPa, and 1.27 +/- 0.28%, respectively. These results suggest the possibility of utilizing melt spinning as a cost-efficient method for fabrication of carbon fibers. (C) 2018 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.