The Study of Conductivity and Preparation for Silver-plated Graphite Particles/Silver Nanopowders Composite Conductive Adhesives
| Autor: | Ti-Chiang Chueh, 闕帝強 |
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| Rok vydání: | 2008 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 96 The thesis was divided into four parts. The first part of study was preparing polyaniline. The second part of study was preparing conductive particles. The third part of study was preparing electrically conductive adhesives (ECAs). The fourth part was alternating some silver-plated conductive particles to Ag nanopowders which the average radius is 100nm. In the experiments, polyaniline was characterized by ultraviolet-visible spectroscopy and the molecular weight of polyaniline was measured by GPC. The particle size and surface morphology were developed by particle size instrument and SEM. We also analyzed whether silver was electroless plated on particles surface or not and plated weight by XRD and ICP. Finally, we prepared ECAs and investaged the effect of changing the compound of conductive particles on resistivity. In the study, polyaniline was prepared and synthesized at 0°C. The molecular weight of polyaniline is 3756. UV–vis spectra of the emeraldine form of polyanoline shows two peaks, 320nm and 640nm. They are the characteristic peaks of the emeraldine form of PANI. After we synthesized the emeraldine form of polyaniline, we doped it by using different doping acids(HCl、HBr、HNO3、H3PO4、DBSA、CH3COOH、HOCH2COOH) and then we solved it in DMSO to measure its conductivity and solubility. In our research of preparing conductive particles, we took the 0.982 μm flake graphite(GS-75) to plate silver electrolessly. We found that there are Ag and Ag2O on GS-75/Ag particles surface by XRD. ICP analysis shows that there are more silver coated on GS-75 surface by electroless plating process with sensitization and activation than the process without sensitization and activation. In the study of preparing electrically conductive adhesives, we can find resistivity ρ decline to 3 x 10-4 ohm-cm after plating silver electrolessly and adding polyaniline solution. The best cruing temperature of ECAs was 200°C. Finally, GS-75/Ag particles were partly alternated to 100nm Ag nanopowders. As the ratio of GS-75/Ag to 100nm Ag is 8：2, and the filling of conductive particles is 60 wt%, the lowest resisticity ρ 7.7 x 10-5 ohm-cm is represented. This is the best resistivity in this thesis. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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