CARBON FIBER, PROCESS FOR PRODUCTION OF POLYACRYLONITRILE-BASE PRECURSOR FIBER FOR CARBON FIBER PRODUCTION, AND PROCESS FOR PRODUCTION OF CARBON FIBER

摘要

A process for the production of polyacrylonitrile-base precursor fiber for carbon fiber production which comprises spinning a spinning dope containing a polyacrylonitrile-base polymer having a limiting viscosity of 2.0 to 10.0 in a concentration of 10 to 25% by weight by a wet spinning method or a dry-wet spinning method, subjecting the obtained fiber to dry and heat treatment, and then steam-stretching the resulting fiber, wherein the extrusion linear speed of the polyacrylonitrile-base polymer from spinnerets is 2 to 15 m/min; and a carbon fiber which is produced by firing the polyacrylonitrile-base precursor fiber obtained by the process and which has a strand tensile modulus of 320 to 380 GPa and a conduction electron density of 3.0 x 10 19 to 7.0 x 10 19 spins/g as determined by electron spin resonance.