The functionalization of spherically shaped carbon-based nanomaterials

Abstract

In this dissertation, the synthesis and characterization of side-chain fullerene-containing polymers has been accomplished and reported (chapter 3). This was achieved by first synthesizing a C60-cyclohexadiene cycloadduct, followed by its polymerization with norbornene via a ring opening metathesis polymerization (ROMP) procedure using the Grubbs’ second generation catalyst. For comparison purposes, 1,4,5,6,7,7-hexachloro-5- norbornene-endo-2,3-heptylimide monomer was also copolymerized with C60- cyclohexadiene cycloadduct. The novel materials were characterized using FT-IR, UVVIS, NMR spectroscopic techniques as well as TGA and DSC analyses. The complex 1,4,5,6,7,7-hexachloro-5-norbornene-endo-2,3-heptylimide was also characterized by single crystal X-ray diffraction. The resulting copolymers revealed that the main fullerene features were retained in the polymers In the second part of this dissertation, carbon spheres (CSs) with high purity were synthesized by the CVD method using acetylene as a carbon source (chapter 4). The CSs were characterized using Raman spectroscopy, TGA and TEM and data revealed their graphitic and crystalline nature. Successful functionalization of CSs with cyclopentadiene (CS-C5H6) and cyclohexadiene (CS-C6H8) was achieved by way of a Diels-Alder type cycloadditon. The functionalized CSs showed good solubility in organic solvents such as chloroform, dichloromethane and DMF. Boron-doped carbon spheres were also synthesized and characterized, with special attention placed on the diameters of carbon spheres obtained in the presence of the boron source. Characterization of the CSs synthesized was performed by means of Raman spectroscopy, TEM, and laser ablation mass spectrometry analysis. The average diameter and shell thickness of the carbon spheres are greatly influenced by the boron incorporation into the CSs, resulting in CSs with a larger diameter.