Patent ID: 7578941

Claim:
A method for separating SWNTs on a basis of length, said method comprising the steps of: a) preparing functionalized SWNTs; wherein the functionalized SWNTs are functionalized with ionizable functional moieties; b) dissolving said functionalized SWNTs in a polar solvent to form a polar phase; c) dissolving an amount of a phase transfer agent in a non-polar solvent to form a non-polar phase; wherein said amount is substoichiometric in relation to the ionizable functional moieties; d) combining the polar phase and the non-polar phase to form a bi-phase mixture; e) adding a cationic donor species to the bi-phase mixture; and f) agitating the bi-phase mixture; wherein the phase transfer agent is electrostatically coupled with at least a portion of the ionizable functional moieties within the bi-phase mixture; and wherein said agitating effects a preferential transport of short SWNTs into the non-polar phase to produce a non-polar phase enriched in short SWNTs and a polar phase enriched in longer SWNTs.