Carbon nanotube fiber and method for producing the same

Abstract

The present invention relates to carbon nanotube fiber and a producing method thereof. The carbon nanotube fiber has a tensile strength which exceeds 5 GPa, and the producing method includes: producing a carbon nanotube fiber precursor consisting of carbon nanotubes; evenly dispersing a cross-linking agent on the carbon nanotube fiber precursor; and acquiring carbon nanotube fiber by thermally treating the carbon nanotube fiber precursor wherein the cross-linking agent is evenly dispersed, wherein the acquired carbon nanotube fiber has cross-linking between wall surfaces of the carbon nanotubes each other.

1 . A carbon nanotube fiber of which a tensile strength exceeds 5 GPa. 
     
     
         2 . The carbon nanotube fiber of  claim 1 , wherein wall surfaces of carbon nanotubes that compose of the carbon nanotube fiber are cross-linked each other. 
     
     
         3 . The carbon nanotube fiber of  claim 2 , wherein the cross-linking results from an acylation reaction between the wall surfaces of the carbon nanotubes. 
     
     
         4 . The carbon nanotube fiber of  claim 3 , wherein the acylation reaction is a one step reaction. 
     
     
         5 . The carbon nanotube fiber of  claim 1 , wherein a diameter of a carbon nanotube is 1 μm to 150 μm. 
     
     
         6 . A method for producing a high-strength carbon nanotube fiber, comprising:
 producing a carbon nanotube fiber precursor consisting of carbon nanotube;   evenly dispersing a cross-linking agent on the carbon nanotube fiber precursor; and   acquiring carbon nanotube fiber by thermally treating the carbon nanotube fiber precursor on which the cross-linking agent is evenly dispersed,   wherein the acquired carbon nanotube fiber has cross-linking between wall surfaces of the carbon nanotubes each other.   
     
     
         7 . The method of  claim 6 , wherein the producing a carbon nanotube fiber precursor consisting of carbon nanotube is performed by one of methods of forest spinning, direct spinning, and solution spinning. 
     
     
         8 . The method of  claim 6 , wherein the producing a carbon nanotube fiber precursor consisting of carbon nanotube is performed by forest spinning. 
     
     
         9 . The method of  claim 6 , wherein producing a carbon nanotube fiber precursor consisting of carbon nanotube comprises:
 preparing a substrate;   growing carbon nanotubes on the substrate; and   drawing out carbon nanotube fiber from the substrate where the carbon nanotubes have been grown.   
     
     
         10 . The method of  claim 9 , wherein the substrate comprises silicon. 
     
     
         11 . The method of  claim 9 , wherein the drawing out of the carbon nanotube fiber precursor from the substrate where the carbon nanotubes have been grown is performed by stretching the carbon nanotubes grown on the substrate in one direction, and pulling out the stretched carbon nanotubes in the form of a noddle. 
     
     
         12 . The method of  claim 9 , wherein the carbon nanotube fiber precursor is formed in the shape of a carbon nanotube ribbon. 
     
     
         13 . The method of  claim 6 , wherein the producing a carbon nanotube fiber precursor consisting of carbon nanotube is performed in a temperature range of 600° C. to 1000° C. 
     
     
         14 . The method of  claim 6 , wherein, in the producing a carbon nanotube fiber precursor consisting of carbon nanotube, at least one selected from a group of C1 to C20 hydrocarbons is used as a carbon source. 
     
     
         15 . The method of  claim 6 , wherein the evenly dispersing of the cross-linking agent on the carbon nanotube fiber precursor is performed by using one of an air gun, a nebulizer, heating, and vacuuming. 
     
     
         16 . The method of  claim 6 , wherein the evenly dispersing of the cross-linking agent on the carbon nanotube fiber precursor is performed by soaking one end of the carbon nanotube fiber precursor in the cross-linking agent in a liquid state. 
     
     
         17 . The method of  claim 6 , wherein the cross-linking agent comprises two or more acyl groups. 
     
     
         18 . The method of  claim 6 , wherein the cross-linking agent is one or more selected from a group including a halogenated acyl compound and a carboxylic acid compound. 
     
     
         19 . The method of  claim 6 , wherein the cross-linking agent is one or more selected from a group including azelaic acid dichloride, poly(acryloyl chloride), azelaic acid, and polyacryl acid, 
     
     
         20 . The method of  claim 6 , wherein the acquiring of the carbon nanotube fiber by thermally treating the carbon nanotube fiber precursor on which the cross-linking agent is evenly dispersed is performed through a one step reaction. 
     
     
         21 . The method of  claim 6 , wherein the acquiring of the carbon nanotube is fiber by thermally treating the carbon nanotube fiber precursor on which the cross-linking agent is evenly dispersed is performed through an acylation reaction. 
     
     
         22 . The method of  claim 6 , wherein the acquiring of the carbon nanotube fiber by thermally treating the carbon nanotube fiber precursor on which the cross-linking agent is evenly dispersed is performed under a nitrogen or inert atmosphere. 
     
     
         23 . The method of  claim 6 , wherein, in the acquiring of the carbon nanotube fiber by thermally treating the carbon nanotube fiber precursor on which the cross-linking agent is evenly dispersed, the thermal treatment is performed in a temperature range of 160° C. to 250° C. 
     
     
         24 . The method of  claim 6 , wherein a diameter of the acquired carbon is nanotube fiber is 1 μm to 150 μm. 
     
     
         25 . The method of  claim 6 , wherein tensile strength of the acquired carbon nanotube fiber is 5 GPa to 40 GPa. 
     
     
         26 . The method of  claim 6 , wherein tensile strength of the acquired carbon nanotube fiber is 30 GPa to 40 GPa.