Grafting organic polymer films on surfaces of carbon nanotubes by surface electroinitiated emulsion polymerization

Diazonium salts coupled with vinylic monomers were able to functionalize carpets of carbon nanotubes by electro‐activation in aqueous media. Hence, nano‐sized carbon surfaces were shown to react with active radical species in solution through a new covalent grafting process called Surface Electroinitiated Emulsion Polymerization (SEEP), where diazonium salts are used both to initiate the polymerization of vinylic monomers in solution and to form a primer grafted polyphenylene‐like layer on the carbon surface. SEM and TEM analyses revealed that ultrathin polymer films are grafted on the sidewalls of carbon nanotubes. XPS spectroscopy further confirmed the functionalization of multi‐walled carbon nanotubes. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)