本研究利用非溶劑誘導相分離(Non-solvent Induced Phase Separation, NIPS)製備並利用混和溶液法(Solution mixing)混摻由奈米銀線(Silver nanowire, AgNW)和多壁奈米碳管(Multi-wall Carbon nanotube, MWCNT)組成之多孔性聚醯亞胺薄膜複合材料，並探討其對電磁波屏蔽效率之影響。
本研究分成兩個部分，使用聚醯亞胺6FDA/4,4’-ODA並由兩步驟合成法合成出聚醯胺酸(Polyamic acid, PAA)作為聚醯亞胺前驅物，製備PAA/AgNW(PPI)、PAA/AgNW/MWCNT(PPIC、PPC)等高分子混和導電填料之溶液，形成之薄膜利用FT-IR鑑定其確認經過高溫環化後成功合成聚醯亞胺，利用TGA鑑定PI/AgNW薄膜中銀線固含量，使用SEM鑑定多孔薄膜中的孔洞結構，並測量導電效果、電磁波屏蔽效果。
利用奈米碳管取代部分奈米銀線的PPIC、PPC薄膜不僅可以降低聚醯亞胺薄膜因銀所造成的熱性質損失，更能達到輕量化、降低成本、增加電磁波吸收效果等目標，本研究中添加奈米銀線的PPI-6薄膜在厚度為29.3μm下其導電率為1.89×102 S/cm，在X-band頻段下其電磁波屏蔽效果可達45.76 dB，透過添加奈米碳管取代部分奈米銀線，PPIC-4薄膜在厚度92.6μm下，導電率為4.39×101 S/cm，電磁波屏蔽效果可達51.90 dB，於此同時，填料成本降低49%、密度減輕39 %，且Td,5%相較PPI-6提升了21.9 ℃。

This study utilizes Non-solvent Induced Phase Separation (NIPS) to fabricate porous polyimide composite films and employs the solution mixing method to blend the composite films with silver nanowires (AgNW) and multi-wall carbon nanotubes (MWCNT). The objective is to investigate the effects of these composites on electromagnetic interference (EMI) shielding effectiveness. By partially replacing the silver nanowires with carbon nanotubes, the PPIC and PPC films not only reduce the thermal property loss caused by silver in the polyimide films but also achieve the goals of lightweight, cost reduction, and enhanced EMI absorption.
In the study, our best sample,PPI-6 film, with only added silver nanowires, has a conductivity of 1.89×102 S/cm at a thickness of 29.3 μm and an EMI shielding effectiveness of up to 45.76 dB in the X-band frequency range. By substituting some of the silver nanowires with carbon nanotubes, the PPIC-4 film achieves a conductivity of 4.39×101 S/cm at a thickness of 92.6 μm and an EMI shielding effectiveness of up to 51.90 dB. Meanwhile, the filler cost is reduced by 49%, density is decreased by 39%, and Td,5% is increased by 21.9 °C compared to PPI-6.

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