Single-wall fullerene nanotubes were converted from nearly endless, highly tangled ropes into short, open-ended pipes that behave as individual macromolecules. Raw nanotube material was purified in large batches, and the ropes were cut into 100- to 300-nanometer lengths. The resulting pieces formed a stable colloidal suspension in water with the help of surfactants. These suspensions permit a variety of manipulations, such as sorting by length, derivatization, and tethering to gold surfaces.

The formation of three-dimensional self-assembled monolayers (3-D SAMs) generated by the adsorption of n-octadecyl disulfide onto colloidal gold and silver nanoparticles is described. The functionalized nanoparticles were characterized by solubility, transmission electron microscopy, ultraviolet−visible spectroscopy, 1H nuclear magnetic resonance spectroscopy, surface-enhanced Raman spectroscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. On gold nanoparticles, this new functionalization method affords crystalline 3-D SAMs that are indistinct from those prepared by the analogous adsorption of n-octadecanethiol. On silver nanoparticles, however, the films derived from n-octadecyl disulfide appear to be somewhat less crystalline than those prepared similarly from n-octadecanethiol. The origin of this difference is briefly explored and discussed.

This paper describes a simple new strategy for preparing poly(9,9-dialkylfluorenyl-2,7-vinylenes) (PFVs) having high molecular weights and no detectable saturated defects along the conjugated backbone. The new route utilizes a modified Horner-Emmons method by coupling suitably designed comonomers to form the targeted conjugated polymers. The newly prepared PFVs were directly compared to PFVs prepared via a previously established Gilch polymerization route. The structure and optical properties of all PFVs were characterized by gel permeation chromatography (GPC), NMR spectroscopy, UV-vis, fluorescence, and photoluminescence spectroscopy. The findings indicate that the modified Horner-Emmons route gave PFVs with lower molecular weights but substantially higher yields and fewer defects than those prepared by using the Gilch route.