Surface Modification of MWCNT and their Reaction with Aniline byOxidative Condensation

Polyaniline composites with multi-walled carbon nanotubes modified by benzene-, amino- and aminobenzene groups were chemically synthesized. FTIR spectroscopy suggests parallel orientation of polyaniline benzene rings to the surface of carbon nanotubes while aminobenzene groups previously grafted to the nanotubes surface participate in oxidative condensation process for aniline and hence cause growth of polymer chain nonparallel in respect to the surface. It is suggested that structural similarity between aminobenzene and aniline facilitates the condensation reaction and results in a higher number of chemical bonds between polyaniline and carbon nanotubes. Surface modification by amino- or aminobenzene groups promotes higher specific electric conductivity and electrochemical capacitance while the modification by benzene groups leads to a steep decrease in the capacitance and one-order of magnitude lower values of electric conductivity.