Influence of magnetic-field-induced-alignment on the conductivity and electromagnetic shielding effectiveness of Ni/polyacrylate coatings
-
摘要: 采用磁場控制導電鎳顆粒在丙烯酸酯乳液中的排列,制備了鎳粉/聚丙烯酸酯復合涂層.采用掃描電鏡對施加磁場前后涂層的微觀形貌進行了表征,研究了磁致取向對復合涂層電導率和屏蔽效能的影響,并結合動力學模型探討了影響磁致取向時間的因素.結果表明,磁致取向可以在涂層中形成"纖維束"狀的微觀組織,提高其電導率,使復合涂層導電滲閥值從5.6%降至3.0%(體積分數).經磁致取向后涂層的屏蔽效能曲線變化均勻,電磁屏蔽效能得到優化;磁致取向時間可以通過改變磁場強度和體系黏度來進行控制.Abstract: Ni/polyacrylate conductive coatings were prepared by utilizing magnetic field to control the alignment of nickel particles in acrylic emulsion. Their surface morphologies with and without the application of magnetic field were analyzed by SEM. The effect of magnetic field on the conductivity and shielding effectiveness of the coatings was studied. In combination with a dynamic model the influencing factors on the time of magnetic-field-induced-alignment (MFIA) was discussed. The results reveal that MFIA helps to generate a yarn-shaped microstructure in the coatings, which improves their conductivity. The percolation threshold of the resulting coatings decreases from 5,6% to 3.0% in volume fraction. Compared to the unaligned, the shielding effectiveness curve presents an even distribution after MFIA, and the electromagnetic shielding effectiveness is optimized. Alignment time can be controlled by changing the system viscosity and the applied magnetic intensity.
-
Key words:
- polyacrylate /
- nickel /
- magnetic field /
- conductivity /
- electromagnetic shielding
-

計量
- 文章訪問數: 254
- HTML全文瀏覽量: 86
- PDF下載量: 5
- 被引次數: 0