Studies to compare and elucidate some of the surface chemical characteristics of chromium dioxide and barium ferrite magnetic particles have been performed. These investigations primarily involved using the technique of flow microcalorimetry to look at the interaction of molecular probes (pyridine, 4-nitrophenol) and various components present in a magnetic ink (dispersants and model binder compounds) with the particles. The interactions were measured in terms of heats of adsorption and adsorption density. Ancillary experiments using FTIR and XPS were also performed. Both electrophoretic measurements and calorimetric studies showed that stabilized CrO₂ was less acidic than un-stabilized CrO₂. Similar measurements showed that un-doped barium ferrite was more acidic than Co and Ti doped barium ferrite. The interactions of dispersants and model binder components with barium ferrite were found to be very exothermic; heats of interaction of greater than -20 kcal/mole were not uncommon. Subsequent analysis of barium ferrite particles treated with dispersants and binder compounds using FTIR and XPS suggested that these compounds formed chemical complexes on the surface of the ferrite particles.
| Identifer | oai:union.ndltd.org:arizona.edu/oai:arizona.openrepository.com:10150/184919 |
| Date | January 1989 |
| Creators | Hudson, Guy Frederick, Hudson, Guy Frederick |
| Contributors | Raghavan, Srini, Lynch, David, Risbud, Subash, Armstrong, Neal R., Pemberton, Jeanne |
| Publisher | The University of Arizona. |
| Source Sets | University of Arizona |
| Language | English |
| Detected Language | English |
| Type | text, Dissertation-Reproduction (electronic) |
| Rights | Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. |
Page generated in 0.0021 seconds