Method of manufacturing carbon fiber and carbon fiber manufactured thereby

Abstract

A method of manufacturing carbon fiber includes (a) preparing a solution by mixing a raw material containing at least one chlorine group in the side chain of a repeat unit with a solvent, (b) forming a fibrous material by spinning the solution, (c) forming a ladder-like chemical ring structure in the fibrous material by hydrothermally treating the fibrous material with a hydrochloric acid solution at a predetermined temperature for a predetermined time, and (d) carbonizing the result of step (c).

1 . A method of manufacturing carbon fiber, comprising:
 (a) preparing a solution by mixing a raw material containing at least one chlorine group in a side chain of a repeat unit with a solvent;   (b) forming a fibrous material by spinning the solution;   (c) forming a ladder-like chemical ring structure in the fibrous material by hydrothermally treating the fibrous material with a hydrochloric acid solution at a predetermined temperature for a predetermined time; and   (d) carbonizing a result of step (c).   
     
     
         2 . The method of  claim 1 , wherein the raw material comprises any one selected from the group consisting of polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), copolymers of vinyl chloride with other monomers, and combinations thereof. 
     
     
         3 . The method of  claim 1 , wherein the raw material has a concentration of 1 wt % to 25 wt %. 
     
     
         4 . The method of  claim 1 , wherein spinning the solution is performed so that a spinning material is discharged into a medium. 
     
     
         5 . The method of  claim 1 , wherein spinning the solution is performed so that a temperature of the solution is 35° C. to 45° C. 
     
     
         6 . The method of  claim 1 , wherein spinning the solution is performed at a discharge rate of 0.5 ml/h to 8 ml/h. 
     
     
         7 . The method of  claim 1 , wherein hydrothermally treating the fibrous material is performed at a hydrochloric acid concentration of 0.1 wt % to 40 wt % in a closed container. 
     
     
         8 . The method of  claim 1 , wherein hydrothermally treating the fibrous material is performed at a temperature of 200° C. to 300° C. 
     
     
         9 . The method of  claim 1 , wherein hydrothermally treating the fibrous material is performed for 20 hours or more. 
     
     
         10 . The method of  claim 1 , wherein carbonizing the result is performed at a temperature of 800° C. to 2,000° C. in an inert gas atmosphere. 
     
     
         11 . The method of  claim 10 , wherein carbonizing the result is performed to reach the temperature at a heating rate of 5.5° C./min or less. 
     
     
         12 . The method of  claim 10 , wherein carbonizing the result is performed by maintaining the temperature for 0.5 to 3 hours. 
     
     
         13 . A carbon fiber obtained by carbonizing a fibrous material having a ladder-like chemical structure, wherein the fibrous material is prepared by spinning of a raw material containing at least one chlorine group in a side chain of a repeat unit and hydrothermal treatment with a hydrochloric acid solution. 
     
     
         14 . The carbon fiber of  claim 13 , having a longitudinal tensile strength of 600 MPa to 1,500 MPa. 
     
     
         15 . The carbon fiber of  claim 13 , having a thickness of 20 μm to 70 μm.