A method for covalent functionalization of multiwalled carbon nanotubes (MWCNTs) was developed using the free radicals generated through Bergman cyclization of enediyne-containing compounds. Four enediyne-bearing Frechet type dendrimers were synthesized in good quantities and characterized. Then, the enediyne-containing molecules were reacted with MWCNTs in N-methyl-2-pyrrolidinone at 206 degrees C under nitrogen. The structure and morphology of the resulting products were characterized by thermogravimetric analysis, ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, and transmission electron microscopy. The dendrimer-functionalized MWCNTs showed good solubility/dispersibility in common organic solvents and polymer solutions. They were used in the formation of polymer composites through electrospinning with polycaprolactone. The results confirmed the surface functionalization of MWCNTs. (C) 2011 Wiley Periodicals, Inc. J Polym Sci Part A: PolymChem 49: 3951-3959, 2011