熱界面材料用之石墨烯/奈米銀線/矽橡膠奈米複合材料之製備及性質研究

Preparation and Characterization of Graphene/ Silver Nanowires /Silicone rubber Nanocomposites for Thermal Interface Material

曾仕竣(Shi-Jun Zeng)

指導教授 ： 馬振基

國立清華大學/工學院/化學工程學系/碩士(2015年)

摘要

本研究旨在製備具有良好熱傳導性質之奈米銀線/石墨烯/矽橡膠高分子複合材料，矽橡膠硬化後的彈性體具有高透明度、柔軟性、寬廣的耐溫範圍(-40~180℃)、尺寸安定性、絕緣性及耐化學品腐蝕等特性，本研究嘗試添加高熱傳導係數的石墨烯及奈米銀線，以改善矽橡膠材料導熱能力不佳的缺點。
本研究第一部分是嘗試以兩種不同方式改質石墨烯，第一種方式是以modified Hummers' method製備氧化石墨烯(Graphene oxide, GO)，並接枝上丙烯醯胺(Acrylamide)，再利用還原劑硼氫化納(NaBH4)進行還原，此種改質石墨烯命名為AA-RGO，另一種方式則是先將GO利用NaBH4進行還原後，所得產物為GNP，再利用催化劑EDC ( 1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide)將Acrylamide接枝於GNP表面，製備出AA-GNP，並將AA-RGO、AA-GNP與未改質石墨烯GNP三種填充材料分別加入Dow Corning® 184 Silicone Rubber (SR)之中，以溶劑法製備成矽橡膠複合材料，由研究結果顯示，添加10 phr AA-RGO之矽橡膠複合材料之熱傳導係數由0.180 W/mK提升至0.412 W/mK，與其他複合材料比較有最顯著的提升效果。
第二部分則是以先前熱傳導係數表現較好的6 phr AA-RGO/SR及10 phr AA-RGO/SR複合材料作為基礎，並添加不同含量之苯硫酚(Thiophenol)進行表面改質的奈米銀線(mAgNWs)，由研究結果顯示，添加10 phr AA-RGO及10 phr mAgNWs矽橡膠複合材料具有最佳的導熱性質，其熱傳導係數由0.18 W/mK增加至1.289 W/mK，尺寸安定性也有顯著改善，熱膨脹係數由310μm/m℃下降至155.5μm/m℃。

關鍵字

矽橡膠 ； 石墨烯 ； 奈米銀線 ； 熱傳導

並列摘要

This study reports the development of graphene/silver nanowire (AgNWs) /silicone rubber nanocomposites with high thermal conductivity. Silicone rubber (SR) processes unusual properties with soft, stable, non-toxic, and non-flammable preperties, however, its thermal conductivityis low. For improving the thermal conductivity, AgNWs and graphene with high thermal conductivity were added to silicone rubber nanocomposites.
In the first part, chemical modification of graphene was by two different methods. The products were assigned to AA-RGO and AA-GNP, respectively. And then AA-RGO/SR, AA-GNP/SR, and unmodified GNP/SR nanocomposites were prepared by solution mixing method. Results indicate that the thermal conductivity of 10 phr AA-RGO/SR nanocomposites increase form 0.180 W/mK to 0.412 W/mK, which processes better thermal conduction than the other nanocomposites.
In the second part, to further enhance thermal conductivity of AA-RGO/SR nanocomposites, AgNWs modified by thiophenol (mAgNWs) are added. The thermal conductivity of silicone rubber nanocomposites which contains 10 phr AA-RGO and 10 phr mAgNWs increases from 0.18W/mK to 1.289 W/mK, and the coefficient of thermal expansion (CTE) reduces from 310μm/m℃ to 155.5μm/m℃.

並列關鍵字

silicone rubber ； graphene ； silver nanowire ； thermal conductivity

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