Carbon nanotube yarn and method for making the same

Abstract

A carbon nanotube yarn includes a number of carbon nanotube yarn strings bound together, and each of the carbon nanotube yarn strings includes a number of carbon nanotube bundles that are joined end to end by van der Waals attractive force, and each of the carbon nanotube bundles includes a number of carbon nanotubes substantially parallel to each other. A method for making the carbon nanotube yarn includes soaking the at least one carbon nanotube yarn string drawn out from a carbon nanotube array in an organic solvent to shrink it and then collecting it.

1 . A method for making a carbon nanotube yarn, the method comprising the steps of:
 (1) providing a carbon nanotube array;   (2) drawing out at least one carbon nanotube yarn string from the carbon nanotube array;   (3) treating the at least one carbon nanotube yarn string using an organic solvent in a manner such that the at least one carbon nanotube yarn string is formed into a single strand of carbon nanotube yarn.   
     
     
         2 . The method as claimed in  claim 1 , wherein the carbon nanotube array is manufactured using a chemical vapor deposition method. 
     
     
         3 . The method as claimed in  claim 1 , wherein the carbon nanotube array is a super-aligned carbon nanotube array. 
     
     
         4 . The method as claimed in  claim 1 , wherein the at least one carbon nanotube yarn string is drawn out from the carbon nanotube array using tweezers. 
     
     
         5 . The method as claimed in  claim 1 , wherein the at least one carbon nanotube yarn string comprises a plurality of carbon nanotube bundles which are joined end to end by van der Waals attractive force, and each of the carbon nanotube bundles comprises a plurality of carbon nanotubes substantially parallel to each other. 
     
     
         6 . The method as claimed in  claim 1 , wherein in step (3), the at least one carbon nanotube yarn string is soaked in the organic solvent thereby forming the at least one carbon nanotube yarn string into a single strand of carbon nanotube yarn. 
     
     
         7 . The method as claimed in  claim 1 , wherein the organic solvent is a volatilizable organic solvent. 
     
     
         8 . The method as claimed in  claim 7 , wherein the volatilizable organic solvent is selected from the group consisting of ethanol, methanol, acetone, dichloroethane, chloroform, and any combination thereof. 
     
     
         9 . A carbon nanotube yarn comprising:
 a plurality of carbon nanotube yarn strings juxtaposedly attached to each other, the carbon nanotube yarn strings each comprising a plurality of carbon nanotube bundles which are joined end to end by van der Waals attractive force, and each of the carbon nanotube bundles comprising a plurality of carbon nanotubes substantially parallel to each other.   
     
     
         10 . The carbon nanotube yarn as claimed in  claim 9 , wherein a diameter of the carbon nanotube yarn is in a range from 20 to 30 microns.