title: Sidewall carboxylic acid functionalization of single-walled carbon nanotubes.
abstract: The reactions of single-walled carbon nanotubes (SWNTs) with succinic or glutaric acid acyl peroxides in o-dichlorobenzene at 80-90 degrees C resulted in the addition of 2-carboxyethyl or 3-carboxypropyl groups, respectively, to the sidewalls of the SWNT. These acid-functionalized SWNTs were converted to acid chlorides by derivatization with SOCl(2) and then to amides with terminal diamines such as ethylenediamine, 4,4'-methylenebis(cyclohexylamine), and diethyltoluenediamine. The acid-functionalized SWNTs and the amide derivatives were characterized by a set of materials characterization methods including attenuated total reflectance (ATR) FTIR, Raman and solid state (13)C NMR spectroscopy, transmission electron microscopy (TEM), and thermal gravimetry-mass spectrometry (TG-MS). The degree of SWNT sidewall functionalization with the acid-terminated groups was estimated as 1 in 24 carbons on the basis of TG-MS data. In comparison with the pristine SWNTs, the acid-functionalized SWNTs show an improved solubility in polar solvents, for example, alcohols and water, which enables their processing for incorporation into polymer composite structures as well as for a variety of biomedical applications.
authors.affiliation: Department of Chemistry and the Center for Nanoscale Science and Technology, Rice University, 6100 Main Street, Houston, Texas 77005-1892, USA.
authors.forename: Haiqing
authors.initials: H
authors.lastname: Peng
authors.forename: Lawrence B
authors.initials: LB
authors.lastname: Alemany
authors.forename: John L
authors.initials: JL
authors.lastname: Margrave
authors.forename: Valery N
authors.initials: VN
authors.lastname: Khabashesku