| Description |
Since the discovery of carbon nanotubes in the 1950s, scientists and engineers have been working on applications that utilize their unique properties. Carbon nanotubes possess extreme conductivity, strength and stiffness which can be used to provide composite materials with improved properties. Cost effective large-scale production is a major challenge for the widespread adoption of carbon nanotubes. A Utah pilot industrial plant has been built to make industrial grade carbon nanotubes. This work seeks to develop appropriate methods for this testing these industrial grade carbon nanotubes. Carbon nanotubes can be studied using a scanning electron microscope (SEM), which is an incredibly powerful tool, however, SEM analysis struggles to provide properties that can be attributed to the bulk powder properties due to the small number observed. The carbon nanotube testing protocols developed in this thesis are devoted to bulk powder methods including: bulk, tap and particle density by helium pyncometry, Brunauer-Emmett-Teller, BET, surface area, temperature programmed oxidation to determine the oxidation temperatures of different types of carbon and the percentage of impurities after oxidation, bulk heat capacity, Raman spectroscopy and Fourier transform infrared spectroscopy, and viscosity. The results of these analytical methods are provided for various types of industrial carbon materials including carbon nanotubes. The analytical results demonstrate that these bulk analytical methods can be used to differentiate various qualities of carbon nanotubes from other types of carbon. Carbon nanotubes show hybridized sp2 bonds with an open p orbital similar to that of graphene. However, the curvature of the nanotube structure allows an analytical distinction between the two using spectroscopy. This curvature and bonding gives the carbon nanotubes a higher level of structure which results in a higher temperature of oxidation, a larger specific heat capacity, and a higher surface area to volume ratio than other carbon species. Carbon nanotubes have an extremely large aspect ratio, the ratio of their length to their diameter. This will cause a unique distortion in the viscosity measurements at a particular volume fraction. |
