Modification of hydroxylated multi-walled carbon nanotubes with a block copolymer

A novel approach was used to improve the dispersibility of multi-walled carbon nanotubes(MWCNTs) in a solvent.Vinyl-functionalized MWCNTs were prepared by the esterification of acrylic acid with hydroxylated MWCNTs.The block copolymer,polystyrene-b-hydroxyethyl methacrylate was synthesized by means of atom transfer radical polymerization.Then the block copolymer was attached to the surface of the MWCNTs through an addition reaction.The products were characterized by FTIR,TGA and TEM.Results indicated that the copolymer was attached to the surface of the MWCNTs by covalent bonds with a content of 42.9%,i.e.every 277 carbon atoms were grafted with a block copolymer chain.The resulting products had a good dispersibility in ethanol.