碳化咖啡灰： 新導電奈米碳材及其電磁波屏蔽測量

Carbonized coffee residues: A new type of conductive nanoparticles and its electromagnetic interference shielding

蔡宗穎

指導教授 ： 徐文光

國立清華大學/工學院/材料科學工程學系/碩士(2014年)

摘要

本實驗主要探討新穎導電奈米碳材料之製備: 碳化的咖啡灰
(carbonized coffee residues)。以環氧樹脂(epoxy)為基材，碳化後咖啡
灰/多壁奈米碳管(multi-walled carbon nanotubes, 多壁奈米碳管)為電
磁波吸收劑，用來進行電磁波屏蔽效應之量測。並利用導電度、介電
常數、阻抗等數值來分析效應。
使用碳化後的咖啡灰為導電性填充物製成高分子試片，實驗結果
可得到良好的電磁波屏蔽效果。並在之後將多壁奈米碳管混入咖啡灰
中製成高分子試片，利用多壁奈米碳管的高導電性和高長徑比特性，
討論多壁奈米碳管對試片屏蔽效應的改變。

關鍵字

電磁波屏蔽 ； 奈米碳管 ； 咖啡

並列摘要

A new type of conductive nanoparticles made by carbonizing coffee residues is demonstrated in this work. Composites made from epoxy and coffee ash/multi-walled carbon nanotubes (MWCNTs) are used as electromagnetic interference (EMI) shielding and shielding effectiveness is analyzed, along with impedance, conductivity and permittivity.
An excellent EMI shielding effectiveness by controlling different proportion of coffee ash in Epoxy matrix is detected. Furthermore, change in EMI shielding effectiveness is presented with dispersion of MWCNTs in coffee ash/Epoxy composites. Shielding phenomenon is explained according to coffee ash/MWCNTs/Epoxy composite’s impedance, conductivity and permittivity.

參考文獻

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