Suspension and dispension of diamond powders with microwave treatment.
| Autor: | Ting-Chun Tseng, 曾鼎鈞 |
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| Rok vydání: | 2012 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 100 Diamond material possesses high hardness, good physical and chemical stability, and has a variety of functional groups formed on the surface with a simple treatment. surface functional groups can change the hydrophilic or lipophilic, and the surface charges with the increased zeta potential. Therefore, it is extensively used in a variety of applications. In this study, diamond suspensions were prepared by dispersing the 2-4 μm diamond powders in deionized water, and treated with a focused microwave. The treatment can enhance zeta potential from the absolute value of 10 mV to about 40 mV. Diamond with zeta potential of 30 mV can be effectively dispersed when the partical size is less than 1 μm. When the diamond particles are larger than 1 μm, we used ethylene glycol with higher viscosity as a solvent and added dispersants to prepare diamond slurry. The results showed that the amine groups of the alkaline dispersant has a better dispersibility. With the addition of poly(vinylpyrrolidone) (PVP) as a second dispersant, the suspension can be enhanced, which derived from the steric hindrance due to formation of the bonding between the groups on diamond surface and PVP. The diamond slurry whith adding of oleylamine and PVP sample has better suspension and dispersibility than the samples with other dispersants. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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