本研究主要目的為利用超臨界流體技術製備二維奈米複合材料，應用於熱介面材料之導熱填料。首先嘗試藉由超臨界二氧化碳的特殊流體性質，結合液相剝離法及超音波震盪，將石墨剝離為單層或少層之結構。接下來，合成以二維碳材料為主體，氮化鋁奈米粒子為輔的奈米複合材料。利用超臨界流體本身特性，協助氮化鋁奈米粒子帶入於少層二維碳材料之層間，構築三明治結構，使兩不同幾何形狀之材料結合並發揮協同效應。氮化鋁同時具備高導熱與高電阻性質，存在於數層石墨烯片狀層間結構，形成三維聲子熱傳導途徑，彌補石墨烯不佳的垂直平面方向之導熱性。此外氮化鋁具高電阻值，存在於石墨烯材料結構中可以有效限制高導電性二維碳材料之導電網路形成，提升複合材料電阻值。第二部分比較四種不同參數之氣相成長碳纖維，探討其相較於同屬一維結構碳材料的奈米碳管之優勢，與石墨化程度對於其增加矽膠之導熱能力的影響。最終，將各種碳材料(石墨、石墨烯奈米片、氣相成長碳纖維W3、W6、Z1、Z2)與混合填料(二維結構碳材料/氮化鋁奈米複合材料)添加於商用矽膠中製作散熱片，以自行搭建之導熱能力量測方法和商用導熱膏做導熱能力比較。實驗結果發現石墨化程度最高的氣相成長碳纖維在水平方向有最佳的導熱能力，然而在垂直於平面方向的導熱能力則所有碳材料添加劑相較商用導熱膏則沒有明顯優勢。混合填料(二維碳材料/氮化鋁奈米複合材料)與只加二維碳材料(石墨、石墨烯奈米片)相較之下，發現混合填料的試片在垂直於平面方向導熱能力較只添加二維碳材料優秀；此外透過高阻計量測散熱片之電阻，不同濃度之混合添料之試片的電阻值能夠較石墨烯增加2~4個數量級，能夠有效解決碳材料當作導熱填料造成熱介面材料失去電阻的情形發生。

In this study, hybrid filler for enhancing thermal conductance of silicone-based nanocomposites without scarifying electrical insulating were demonstrated. This was done by introducing intercalated electrically insulating aluminum nitride (AlN) into electrically conductive exfoliated graphite/ graphene nanoplatelet (GNP) in the nanocomposite by supercritical CO2 (ScCO2) process. ScCO2 ‘s low surface tension and viscosity lead to greater penetration into porous solid. Silicone composites with hybrid filler of AlN/ exfoliated graphite and AlN/ GNP nanocomposite were fabricated using a three roll mills machine. Scanning electron microscopy and Transmission electron images reveal that AlN nanoparticles were successfully introduced into the layer structure of the 2D carbon-based materials and were uniformly dispersed in the silicone matrix. AlN nanoparticles cannot only hinder electrical conduction of 2D carbon-based materials but also can form a 3D phonon transport channel. The electrical resistance and thermal conductance of thermal interface layers of epoxy composites were discussed. Compare to silicone composites with only exfoliated graphite or GNP, hybrid silicone composites with AlN and exfoliated graphite/GNP not only maintain polymer’s electrically insulation but also enhance through-thickness thermal conductance, which make these hybrid fillers an attractive candidate for electronic field applications especially thermal interface materials (TIMs).

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