US Patent 7357906 - Single walled CNT separation

http://www.freepatentsonline.com/7357906.html

This patent originating from research by Richard Smalley's group at Rice University has priority going back to Aug. 8, 1996 and seems fairly basic to single walled carbon nanotube separation by type. Claim 1 reads:

1. A method comprising: a) providing a mixture of single-wall carbon nanotubes; b) derivatizing the single-wall carbon nanotubes; c) dispersing the single-wall carbon nanotubes; and d) fractionating the mixture by a characteristic selected from the group consisting of lengths, diameters, helicities and combinations thereof.