Covalent Functionalization of Multiwalled Carbon Nanotubes with Polybutadiene

Covalent functionalization of multiwalled carbon nanotubes (MWNTs) with polybutadiene was accomplished by coupling of isocyanate-decorated MWNTs with hydroxyl-terminated polybutadiene (HTPB) in dry toluene. The MWNT precursor, isocyanate-functionalized MWNTs, was prepared by directly reacting commercial hydroxyl functionalized MWNTs with excess toluene 2,4-diisocyanate (TDI). HTPBs with different molecular weights (M-n = 1900, 2600, and 3600 g/mol) were subjected to this coupling reaction, resulting in the formation of polymer functionalized MWNTs. FTIR spectroscopy was utilized to follow the introduction and consumption of isocyanate groups on the MWNTs. Thermogravimetric analysis (TGA) indicated that HTPB was successfully grafted onto MWNT surface, with the final products having a polymer weight percentage of around 30 wt %. Transmission electron microscopy (TEM) was utilized to image the polymer functionalized MWNTs, showing relatively uniform polymer coatings presented on the surface of MWNTs. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 116: 1272-1277, 2010