近年來，全球暖化和氣候變遷已經成為全球關注的焦點議題。被動日間輻射冷卻作為不用外部能量輸入的散熱技術，正受到越來越多的關注。然而目前的散熱器中，仍然存在如高成本、製造與應用困難、製程複雜等問題。本研究旨在使用具有低設備門檻，製程簡易且材料製備容易的光固化3D列印製造散熱器，易於控制成品幾何形狀且能夠透過搭配各類PDRC效應填料提升散熱效應。
本研究開發了一種基於非晶矽氧化物（SiO2）奈米粒子混合光固化高分子材料的材料配方，並使用DLP 3D列印技術製造散熱器。透過FTIR實驗，選擇了在大氣窗口具有良好紅外輻射能力的丙烯酸酯基寡聚物與單體作為高分子材料。漿料製備中，改良了傳統製程並使粉末有效分散於樹脂中。針對散熱效應的評估，日照結果發現，樣品的溫度與降溫幅度成正相關；而在大氣溫度為33-36攝氏度，控制組的未貼附散熱器之鋼板溫度為74.6攝氏度的條件下，這種輻射冷卻器能夠產生比控制組低18.5攝氏度的表面冷卻效果。此外，還進行了連續7天的日照實驗，驗證了每日均有相當的冷卻效果。實際應用方面，在GoPro之使用上有實質的冷卻效果，升溫幅度由5.8攝氏度改善至1.1攝氏度，有效解決戶外小型機械的過熱問題。

In recent years, global warming and climate change have become the focal point of global concern. Passive Daytime Radiative Cooling (PDRC) technology, as a passive and environmentally friendly cooling strategy, has attracted increasing attention due to its lower energy consumption compared to traditional cooling methods. However, various radiative cooling devices still face some challenges, such as the high cost and manufacturing difficulties of multi-layer thin-film and patterned surface radiative coolers, as well as the continuous questioning of the cooling effectiveness in polymer thin-film and coating radiators due to material aging.
DLP 3D printing offers rapid and cost-effective manufacturing with low equipment requirements, addressing the limitations of widespread adoption of multi-layer thin-film and patterned surface radiative coolers. By incorporating various PDRC-effect fillers, this technology enhances the cooling performance and provides high geometric customization capabilities, showcasing substantial potential for development in the PDRC field.
Therefore, this study developed a manufacturing method for radiative coolers using a combination of amorphous silicon oxide (SiO2) nanoparticles and light-curable high polymer materials, 3D printed using DLP technology. Acrylate-based oligomers and monomers with infrared emissivity were selected as the high polymer materials. The evaluation of cooling effectiveness revealed promising results. Under atmospheric temperatures of 33-36 degrees Celsius, the radiative cooler demonstrated a surface cooling effect of 18.5 degrees Celsius lower than the control group's steel plate temperature of 74.6 degrees Celsius, validating its cooling capabilities. Additionally, a continuous 7-day sunlight exposure experiment confirmed the stability of the cooling effect. In practical applications, the radiative cooler exhibited substantial cooling effectiveness in the use of GoPro, reducing the temperature increase from 5.8 degrees Celsius to 1.1 degrees Celsius, effectively addressing overheating issues in outdoor small machinery.

Gibson, I., Rosen, D. W., Stucker, B., Khorasani, M., Rosen, D., Stucker, B., & Khorasani, M.., Additive manufacturing technologies. Vol. 17. 2021: Springer.
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