Single-walled and multiple-walled carbon nanotubes were functionalized with a polystyrene copolymer, poly(styrene-co-p-(4-(4′-vinylphenyl)-3-oxabutanol)). The functionalization reaction conditions were designed for the esterification of the nanotube-bound carboxylic acids. The polymer-attached carbon nanotubes are soluble in common organic solvents, making it possible to characterize the samples using not only solid-state but also solution-based techniques. The solubility has also allowed an intimate mixing of the functionalized carbon nanotubes with polystyrene. Results from the characterization of the functionalized carbon nanotubes, including the chemical and thermal defunctionalizations of the soluble samples, and the fabrication of polystyrene-carbon nanotube composite thin films using a wet-casting method are presented and discussed.

In the preparation of high-quality polymeric carbon nanocomposites, the full compatibility of carbon nanotubes as the filler with the matrix polymer is required. For such a purpose, an amino-terminated polyimide, specifically designed to be structurally identical to the matrix polymer, was synthesized and used in the functionalization of carbon nanotubes. The functionalized carbon nanotube samples were analyzed and studied by using a series of techniques, and the results are presented and discussed. These nanotube samples and the matrix polyimide are soluble in the same organic solvents, allowing their intimate mixing in solution and the subsequent fabrication of polyimide-carbon nanotube composite films via wet-casting. According to results from the spectroscopic and electron microscopic characterizations, the carbon nanotubes are homogeneously dispersed in the nanocomposite films.

Individual and thin bundles of aminopolymer-functionalized single-walled carbon nanotubes (SWNTs) were successfully imaged using high-resolution transmission electron microscopy (HR-TEM). The corresponding electron energy loss spectroscopy (EELS) characterization of the same TEM specimen before and after ex situ thermal defunctionalization confirmed that the nanotube surface was covered with nitrogen-containing functionalities in the functionalized SWNT sample.

Single-walled and multiple-walled carbon nanotubes were functionalized with derivatized polyimide for the homogeneous dispersion of the nanotubes. For the functionalization, the nanotube-bound carboxylic acids derived from the surface defects were targeted for esterification reactions with pendant hydroxyl groups in the derivatized polyimide. The functionalized nanotube samples, readily soluble in several common organic solvents, were thoroughly characterized by a series of instrumental techniques including NMR in both solution phase and solid state, optical absorption, Raman, thermogravimetric analysis, and microscopy methods. The results were consistent with well-dispersed nanotubes functionalized by the polyimide, and also with the expectation that the nanotube electronic properties were largely preserved in the specific mode of functionalization. The presumed formation of ester linkages in the functionalized samples was supported by the results from chemical defunctionalization. The potential applications of the polyimide-functionalized carbon nanotubes and the demonstrated functionalization strategy are discussed.

Carbon nanotubes were functionalized by polystyrene copolymers, poly(styrene-co-hydroxymethylstyrene) and poly(styrene-co-aminomethylstyrene), under esterification and amidation reaction conditions, respectively. The polymer-attached carbon nanotubes are soluble in common organic solvents, forming colored homogeneous solutions. Results from the characterization of the functionalized carbon nanotubes are presented and discussed.

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Reaction of the bis-9-BBN adduct of several dienes with 1,3-dibromobenzene via Suzuki coupling leads to a series of [n]metacyclophanes ranging in size from 10 to 17 atom members. In each case, two carbon-carbon bonds are formed in one reaction vessel. However, when the bis-9-BBN adduct of 1,5-hexadiene is coupled with a variety of aryl dihalides, larger [n.n]cyclophanes were formed in preference to the [n]cyclophanes. Four carbon-carbon bonds are formed in this instance. Single-crystal X-ray analyses of these [n.n]cyclophanes reveal interestingly shaped molecules with large cavities.

CyclophanesCyclophanes O 0450 Synthesis of [n]-and [n.n]Cyclophanes by Using Suzuki-Miyaura Coupling. -A number of novel cyclophanes are prepared. -(SMITH, B. B.; HILL, D. E.; CROPP, T. A.; WALSH, R. D.; CARTRETTE, D.; HIPPS, S.; SHACHTER, A. M.; PENNINGTON, W. T.; KWOCHKA*, W. R.; J. Org. Chem. 67 (2002) 15, 5333-5337; Dep. Chem., Western Carolina Univ., Cullowhee, NC 28723, USA; Eng.) -Jannicke 03-056