Water-redispersible isolated single-walled carbon nanotubes fabricated by in situ polymerization of micelles

A new type of noncovalently functionalized isolated single walled carbon nanotubes (SWNT) powder that is easily dispersible in water by only ten minutes of mild vortex mixing was investigated. The mixture of SWNT and CTVB was sonicated for one hour to exfoliate bundled SWNT and produce individually isolated SWNT with an adsorbed layer of CTVB. NMR measurements of the polymerized mixture showed that peaks corresponding to vinyl groups were almost completely absent, indicating nearly 100% polymerization of the counterions. The polymerized mixture was ultracentrifuged to separate the isolated SWNT from the bundled ones. The decanted mixture was filtered through a membrane with pores of 0.22 μm. The p-SWNT powder was easily dissolved in water at the same concentration as before freeze-drying with only ten minutes of mild vortex mixing. It was observed that the p-SWNT do not form any aggregates or networks at the concentrations.