Modified carbon nanotubes and their compatibility

Abstract

Modified carbon nanotubes are provided having carbon nanotube core covalently bound through C—C bonds to a polymer shell surrounding the carbon nanotube core. The polymer shell is a polymer having functional groups pointing outwardly from the shell. The functional groups are compatible with or able to covalently connect to another polymer. Such modified carbon nanotubes are more readily dispersed in a homogeneous manner in another polymer and may be used as a reinforcing filler in a polymer matrix. The modified carbon nanotubes with a core-shell structure in which the core has a substantially unidirectional orientation within the shell are produced by reacting neutral carbon nanotubes with 4-vinylaniline through a diazonium reaction in presence of one or more types of multifunctional monomers carrying a vinyl moiety and one or more functional groups for compatibilization with or connection to another polymer. The reaction is conducted at an elevated temperature without isolation of intermediates and without addition of any extra initiator or catalyst to form a polymer shell in situ around the carbon nanotube. The polymer shell is covalently bound to CNT sidewall through C—C bonds and has functional groups outwardly pointing from the shell for compatibilization with or connection to another polymer.