Soluble dendron-functionalized carbon nanotubes: Preparation, characterization, and properties

Lipophilic and hydrophilic dendra which are terminated with long alkyl chains and oligomeric poly(ethylene glycol) moieties, respectively, were synthesized, and these dendron species were used to functionalize single-wall (SWNT) and multiple-wall (MWNT) carbon nanotubes via amidation and esterification reactions. The functionalized carbon nanotube samples are, depending on the functionalities, soluble in common organic solvents, such as hexane and chloroform, and water to form colored homogeneous solutions. Characterizations using NMR, electron microscopy, and optical spectroscopic techniques show that the homogeneous solutions contain carbon nanotubes. A preliminary understanding of the structural features and properties of these soluble dendron-functionalized SWNTs and MWNTs is discussed in terms of results from the characterizations, the defunctionalization reactions, and the trapping of metal nanoparticles by the functionalized nanotubes in solution.