Wrapping of single-walled carbon nanotubes with A-B-A block telomers

Single-walled carbon nanotubes (SWNTs) mechanically dispersed in HEPES buffer were incubated with a dispersion of A-B-A block telomers, composed of 2-methacryloyloxyethyl-D-glucopyranoside telomers (A block) and a styrene telomer (B block), which had been prepared by the macroinitiator technique. After the incubation, the polymer-wrapped SWNT could be stably dispersed in the buffer without any precipitation for several months. The glucose residue above the SWNT was definitely recognized by lectin (Concanavalin A) as proven by the increase in turbidity. Using a similar procedure, a block telomer composed of N-isopropylacrylamide telomers (A block) and a styrene telomer (B block) could easily be deposited onto the SWNT. A temperature-responsive aggregation and the subsequent precipitation of the modified SWNT could clearly be observed. The usage of the block-telomer examined here would be promising for the preparation of stable dispersions of SWNTs with various functions.