Lebron-colon, mar Isabel B.S. University of Puerto Rico- humacao campus, 1998, 2005
Lebon-Colon, Marisabel
2005-05-01
2000-2009
An improved procedure for the purification of single wall carbon nanotubes produced by the HiPCO process has been developed. This improved procedure has the advantage of allowing successful purification of gram quantities of HiPCO SWNTs, in contrast to the literature procedure that report the purifications of less than 100 mg batches. Large amounts of purified carbon nanotubes are essential for their further use in the preparation of novel materials and components. Another advantage of this improved procedure is that it substantially reduced the amount of synthesis impurities, catalyst, and non-nanotube forms of carbon within the carbon nanotubes resulting in significant increases in their stability. A design of experiment (DOE) based optimization was utilized in the development of this improved purification method. A method was developed to produce stable suspensions of purified HiPCO SWNTs in DMF/NMP using ultra-sonication. The chemical reactivity of the purified HiPCO SWNTs in the presence of benzyne generated in situ by different approaches was studied. Functionalization of the SWNTs was successful when benzyne was generated in low concentration in situ from benzyene precursors. Thermal and spectroscopic analysis of the functionalized nanotubes confirm that Diels-Alder addition of benzyne to nanotubes had occurred. The extent of functionalization of the surface of the nanotubes was determined to range from 9 to 16 % based upon TGA. It was possible to form stable suspensions of the purified nanotubes treated with polycyclic aromatic hydrocarbon derivatives. These complexes nanotubes can be readily dispersed in organic solvents to provide colloidal suspensions that are stable for days at room temperature. It was shown that noncovalent functionalization allows more efficient dispersion of the purified single wall carbon nanotubes throughout a thermoplastic polyimide resulting in a substantially greater enhancement in the tensile strength and conductivity properties of the polymeric film than those realized with the incorporation of purified single carbon nanotubes which had not been functionalized.
text
application/pdf
dissertation
Doctor of Philosophy (PhD)
Clark Atlanta University
Department of Chemistry
Mintz, Eric A.
Georgia--Atlanta
http://hdl.handle.net/20.500.12322/cau.td:2005_lebon_colon_marisabel
https://rightsstatements.org/page/InC-EDU/1.0/
