碳基高性價比散熱塗料之製備技術開發

Abstract

隨著技術的進步，電子元件的效能不斷的增加，而體積亦朝向小型化發展，無可避免地，如何的幫助元件有效地散熱將構成挑戰。散熱塗層( Heat dissipating coat)由高分子材料構成基底，添加高熱輻射係數與高導熱性質的填料，能夠快速將所塗佈物體所產生的熱傳導至高熱輻射係數的塗層中，使得物體藉由熱輻射傳導至環境中的熱能大幅提升，屬於被動散熱的一種，設計散熱系統時也能與散熱鰭片搭配而獲得更好的效果，提供設計人員更多樣化的選擇。而目前的文獻較常見為使用通稱為奈米碳材的石墨烯以及奈米碳管作為填料，再藉由添加陶瓷粉末形成協同效應(Synergetic effect)來促進輻射散熱的效果。雖被證實有效，但受限於奈米碳材的成本高昂且不易大量生產，使得散熱塗料的推廣使用不易。此研究為奠基於本實驗室之前的成果，將原本的陶瓷添加物改為氧化鋁粉末，並改以常見且成本較低廉的碳黑、石墨粉和活性碳粉作為促進散熱的填料製備壓克力散熱塗料，再將完成的塗料噴塗於鋁片之上做為10 W的LED模組之散熱片，經實驗觀察在適當的添加量下最高能達到13.2 °C的降溫，而相比之下以1:1之重量比的石墨烯和多壁奈米碳管混合物做為填料的散熱塗料的試片最高降溫為13.7 °C，相差僅為0.5 °C，由此實驗結果可知本研究成功開發了一種高性價比的散熱塗料，並在成本上能滿足消費級產品的需求。As technology advances, the performance of electrical devices keeps increasing, while their size keeps decreasing. That poses challenges for how to effectively dissipate heat in electrical devices. Heat dissipating coatings, which is a method of passive cooling, consists specific kind of polymer as the matrix, and high emissivity/thermal conductivity fillers, when cured, can quickly take away heat from the covered object and dissipates it to the environment and can be combined with a regular heatsink to achieve better results, providing designers more choices. Current researches usually focus on adding graphene and carbon nanotube as fillers and combining them with ceramic powder to acquire a synergetic effect, further improving the effects of radiant cooling. Although it’s proved to be effective, the costs of graphene and carbon nanotube are expensive; Moreover, these materials are difficult to be mass-produced, limiting the use of heat-dissipating coatings.This study is based on the former research results of the laboratory, replacing the original ceramic additive with aluminum oxide, and choosing relatively low-cost materials like carbon black, natural graphite powder, and activated carbon powder as heat-dissipating promoting fillers to produce the paint. By experiment, it is observed that the LED chip used in this study, when attached to the aluminum substrates with adequate filled coating, the temperature drop can reach 13.2 °C. In contrast, when the LED chip attached to the aluminum substrate of which coating is added with a 1:1 mixture of graphene and MWCNT, the temperature drop reached 13.7 °C, merely lowered 0.5 °C. As a result, this study successfully developed a highly cost-effective heat-dissipating paint that meets the needs of consumer products.