Method for preparing carbon fiber precursor

Abstract

Disclosed is a method for preparing a precursor fiber for a carbon fiber. The precursor fiber of fine denier according to the present invention is used to prepare a carbon fiber having excellent tensile strength and compressive strength by a conventional single component spinneret using a superdrawing process to prepare a high strength and high elastic carbon fiber with a reduction in stabilization time.

What is claimed is: 
     
         1 . A method for preparing a precursor fiber for a carbon fiber, the method comprising:
 spinning an acrylonitrile fiber from a spinning dope containing an acrylonitrile polymer;   in response to spinning, controlling the fiber diameter by superdrawing the fiber spun in the first step; and   in response, preparing a precursor fiber by drawing the controlled.   
     
     
         2 . The method of  claim 1 , wherein the acrylonitrile polymer is prepared by copolymerization with at least one monomer selected from the group consisting of acrylic acid (AA), methacrylic acid (MA), itaconic acid (IA), methacrylate (MA), and acrylamide (AM). 
     
     
         3 . The method of  claim 1 , wherein the polyacrylonitrile comprises 90 to 99 wt % of acrylonitrile. 
     
     
         4 . The method of  claim 1 , wherein the spinning dope comprises 5 to 25 wt % of acrylonitrile polymer is mixed with a solvent selected from the group consisting of dimethylsulfoxide (DMSO), N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), and nitric acid. 
     
     
         5 . The method of  claim 1 , wherein the superdrawing is performed at a temperature above the glass transition temperature of the acrylonitrile. 
     
     
         6 . The method of  claim 5 , wherein the superdrawing is performed at a temperature of 100 to 180° C. 
     
     
         7 . The method of  claim 5 , wherein the superdrawing is performed at a strain rate of 0.4 to 400 l/sec 
     
     
         8 . A precursor fiber for a carbon fiber prepared by the method of  claim 1 . 
     
     
         9 . The precursor fiber of  claim 8 , wherein the precursor fiber has a diameter of 0.05 to 0.5 denier. 
     
     
         10 . A carbon fiber prepared using the precursor fiber of  claim 8 .