Modified carbon nanotubes using controlled polymer crystallization

Abstract

A process for the modification of carbon fibers and/or carbon nanotubes, including 1-dimensional nanowire and nanofiber structures. In the process, certain polymeric materials are crystallized on a surface of the carbon fibers and/or carbon nanotubes. The crystallization process may be carried out under controlled conditions to produce a variety of useful modifications, including modifications at discrete intervals, as well as functional modifications. Also disclosed are carbon fibers, carbon nanotubes and nano-hybrid structures made by the modification process of the present invention.

1 . A method for the modification of carbon fibers or carbon nanotubes comprising the step of: 
 crystallizing a polymeric material on a surface of the carbon fibers or carbon nanotubes.    
   
   
       2 . A method as claimed in  claim 1 , wherein the carbon fibers or carbon nanotubes are modified at substantially periodic intervals on a surface of the carbon fibers or carbon nanotubes.  
   
   
       3 . A method as claimed in  claim 1 , wherein functional groups are attached to said polymeric material prior to, during or subsequent to said crystallization step.  
   
   
       4 . A method as claimed in  claim 1 , wherein said carbon fibers or carbon nanotubes comprise 1-dimensional nanowire structures and 1-dimensional nanofiber structures.  
   
   
       5 . A method as claimed in  claim 1 , wherein said carbon nanotubes are selected from the group consisting of single-walled carbon nanotubes and multi-walled carbon nanotubes.  
   
   
       6 . A method as claimed in  claim 1 , wherein the crystallization step comprises solution crystallization.  
   
   
       7 . A method as claimed in  claim 6 , wherein, prior to the crystallization step, said carbon nanotubes are unbundled.  
   
   
       8 . A method as claimed in  claim 1 , wherein said polymeric material is selected from the group consisting of polyolefins, nylons, polyethylene oxide and poly(phenylene sulfide).  
   
   
       9 . A method as claimed in  claim 1 , wherein said polymeric material is selected from the group consisting of polyethylene, polypropylene and nylon 6,6.  
   
   
       10 . A method as claimed in  claim 6 , wherein the carbon fibers or carbon nanotubes are present at a concentration of 0.001%-1% by weight, based on a total weight of a solution employed in the solution crystallization step.  
   
   
       11 . A method as claimed in  claim 10 , wherein the polymeric material is present at a concentration of 0.01% to about 1% by weight, based on a total weight of a solution employed in the solution crystallization step.  
   
   
       12 . A method as claimed in  claim 1 , wherein a crystallization time for the crystallization step is from about 0.1 hours to about 10 hours.  
   
   
       13 . A method as claimed in  claim 1 , further comprising the step of removing a portion of the polymeric material from a surface of the carbon fiber or carbon nanotube, subsequent to said crystallization step.  
   
   
       14 . A method as claimed in  claim 13 , further comprising the step of applying a second polymeric material to said carbon fiber or carbon nanotube, subsequent to said step of removing a portion of said first polymeric material from a surface of said carbon fiber or carbon nanotube.  
   
   
       15 . Carbon fibers and carbon nanotubes made by the process of  claim 1 .  
   
   
       16 . Carbon fibers and carbon nanotubes as claimed in  claim 15 , having a periodicity of functionalization by said polymeric material of about 20 to about 120 nm.  
   
   
       17 . Carbon fibers and carbon nanotubes made by the process of  claim 3 .  
   
   
       18 . Carbon fibers and carbon nanotubes made by the process of  claim 14.