Encapsulation of multi-walled carbon nanotubes by poly(4-vinylpyridine) and its dispersion stability in various solvent media

MWNTs were effectively functionalized with KMnO4 in the presence of a phase transfer catalyst at room temperature. The hydroxyl functionalized MWNTs were reacted with a vinyl group-carrying silane-coupling agent and the terminal vinyl groups were used to fabricate poly(4-vinylpyridine) brushes by solution polymerization. Finally, P4VP-encapsulated MWNTs were obtained. The resulting materials were analyzed using TEM, TGA and their dispersion stability in various solvents was characterized by Turbiscan. It was found that the dispersion stability of P4VP-encapsulated MWNTs is dramatically improved in alcoholic medium due to the chemical affinity of P4VP with alcohol. This functionalization technique would provide a facile route to prepare various polymer brushes on the surface of MWNTs in order to improve the dispersion of MWNTs for potential applications.