ACRYLONITRILE COPOLYMER AND METHOD FOR MANUFACTURING THE SAME, AND ACRYLONITRILE COPOLYMER SOLUTION AND POLYACRYLONITRILE PRECURSOR FIBER FOR CARBON FIBER AND METHOD FOR MANUFACTURING THE SAME

摘要

Provided are an acrylonitrile copolymer that is excellent in thermal stability as a solution (spinning dope) when dissolved in an amide solvent and can form dense polyacrylonitrile fiber suitable for manufacturing carbon fiber, an acrylonitrile copolymer solution obtained by dissolving the acrylonitrile copolymer in an amide solvent, and a method for manufacturing polyacrylonitrile precursor fiber for carbon fiber, the polyacrylonitrile precursor fiber using the acrylonitrile copolymer solution.  An acrylonitrile copolymer contains 1.0 × 10-5 equivalent/g or more of sulfonic acid groups derived from a polymerization initiator and the value (equivalent ratio) of (the content of sulfuric acid groups derived from the polymerization initiator/the total content of the sulfonic acid groups and the sulfuric acid groups) is 0.4 or less.  An acrylonitrile copolymer solution contains the acrylonitrile copolymer and an amide solvent.