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Dispersion and exfoliation of single wall carbon nanotubes (SWNTs) have been studied in poly(acrylonitrile) (PAN), poly(p-phenylene benzobisoxazole) (PBO) solutions, and composite fibers using transmission electron microscopy. As a result of polymer assisted dispersion and exfoliation, the average SWNT bundle diameter in SWNT/ PAN (5/95) was 11 nm, while the average diameter for the pristine SWNT bundles was about 30 nm. High resolution TEM of SWNT/PBO (10/90) composite fibers did not reveal the presence of SWNT aggregates or bundles, suggesting SWNT exfoliation as individuals. On the other hand, both oriented and unoriented nanotube bundles have been observed in SWNT/PBO samples containing 15 wt % nanotubes. Carbon nanotubes are 10 5 times more radiation resistant than flexible polymers such as polyethylene, and 10 3 times more resistant than highly radiation resistant polymers such as PBO. Therefore in the high resolution TEM study of nanotube/polymer composites, nanotubes can be observed long after the polymer has been damaged by electron radiation.

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Single-walled carbon nanotubes (SWNTs) were well dispersed in both water and organic solvent by the use of fullerodendron as a dispersant. A C60 moiety at the focal point of dendron plays a crucial role in the dispersing process, because dendron having an anthracene unit at the focal point can not disperse SWNTs in THF. The dispersions of SWNTs were characterized by UV–vis–NIR spectroscopy, Raman spectroscopy, SEM, HRTEM, and AFM.

Single-walled carbon nanotube (SWNT)/ poly(methyl methacrylate) and SWNT/polyacrylonitrile composite nanofibers were electrospun with SWNT bundles as the cores and the polymers as the shells. This was a novel approach for processing core (carbon nanotube)-shell (polymer) nanofibers. Raman spectroscopy results show straininduced intensity variations in the SWNT radial breathing mode and an upshift in the tangential (G) and overtone of the disorder (GЈ) bands, suggesting compressive forces on the SWNTs in the electrospun composite fibers. Such fibers may find applications as conducting nanowires and as atomic force microscopy tips.