METHOD OF MANUFACTURING POLYACRYLONITRILE TYPE PRECURSOR FIBER FOR CARBON FIBER AND POLYACRYLONITRILE TYPE PRECURSOR FIBER MANUFACTURED THEREBY

摘要

The present invention relates to a method for manufacturing polyacrylonitrile-based precursor fiber for carbon fiber. When manufacturing an acrylonitrile-based copolymer into polyacrylonitrile-based precursor fiber for carbon fiber by passing acrylonitrile-based filament through the processes of washing with water, hot water stretching, primary drying, hot-steam stretching, secondary drying and winding, secondarily dried polyacrylonitrile-based filament is irradiated. The polyacrylonitrile-based precursor fiber for carbon fiber manufactured by the method of the present invention has a specific gravity of 1.2-1.4 and is thermally stabilized as the cyclization reaction is conducted in a portion of pyridine in the molecular structure by the irradiation. As a result, the polyacrylonitrile-based precursor fiber for carbon fiber manufactured according to the present invention can shorten the heat stabilization treatment time for the manufacture of carbon fiber, and can perform the oxidation process for the manufacture of carbon fiber only for a short period of time at a relatively lower temperature compared to the past due to a decreased heating value in the oxidation process, thereby simplifying the manufacture process of carbon fiber and enhancing the productivity.