Synthesis and characterization of pyrene bearing amphiphilic miktoarm star polymer and its noncovalent interactions with multiwalled carbon nanotubes

A novel amphiphilic miktoarm star polymer, polystyrene-poly(ethylene glycol)-poly(methyl methacrylate), bearing a pyrene group at the end of PS arm (Pyrene-PS-PEG-PMMA) was successfully synthesized via combination of atom transfer radical polymerization and click chemistry. The structure and composition of the amphiphilic miktoarm star polymer were characterized by gel permeation chromatography and 1H NMR. The functionalization of multiwalled carbon nanotubes (MWCNTs) via pp stacking interactions with pyrene-PS-PEG-PMMA miktoarm star polymer was accomplished and the resulting polymer-MWCNTs hybrid was analyzed by using 1H NMR, UVvis, fluorescence spectroscopy, and thermal gravimetric analysis. The high-resolution transmission electron microscopy and analytical techniques aforementioned confirmed that the noncovalent functionalization of MWCNT's with the amphiphilic miktoarm star polymer was successfully achieved. The MWCNT/pyrene-PS-PEG-PMMA exhibited significant dispersion stability in common organic solvents such as dimethyl formamide, chloroform, and tetrahydrofuran. (c) 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012