源自深共熔溶劑的共熔凝膠是個新興的材料。擁有著優異的光學、機械、穩定性。因此在在軟性設備應用中顯示出巨大的潛力。然而，由於深共熔溶劑對水的敏感度較高，將其暴露於大氣下長時間會造成其變質，尤其是應用於3D列印當中。因此開發一種對環境穩定的共熔凝膠仍然具有挑戰性。
本研究探討了使用數位光處理和基於疏水性深共熔溶劑的樹脂來製造電容式感測器的介電層。所使用的樹脂是由薄荷醇和癸酸組成的第 V 型疏水性深共熔溶劑。藉由此樹脂中兩種單體異丙基丙烯醯胺和丙烯酸的共聚合，可形成透明凝膠。深共熔溶劑和異丙基丙烯醯胺之間的強氫鍵以及軟鏈段和硬鏈段的相分離可實現快速光聚合，無需化學交聯劑即可形成堅韌的凝膠。與有機凝膠相比，共熔凝膠具有顯著的韌性和自癒特性。此外，該凝膠具有高效的能量耗散和快速的自我恢復能力。最後，我們利用3D列印製造具有金字塔狀的微結構介電層。這種結構顯著增強了結構的局部變形，從而提高了靈敏度。這項研究展示了3D列印疏水性深共熔溶劑的簡單策略，從而透過DLP技術開發出高韌性和自修復材料。

Eutectogels derived from deep eutectic solvent (DES) are emerging as promising materials, notable for their excellent optical, mechanical, and stable properties. These qualities make them highly suitable for applications in flexible devices. However, the high sensitivity of most DES to water poses a significant challenge. Prolonged exposure to the atmosphere can lead to deterioration, which is particularly problematic in 3D printing applications. Thus, developing environmentally stable eutectogels remains a critical challenge.
This study explores the fabrication of dielectric layers for capacitive sensors using digital light processing (DLP) with hydrophobic DES-based resins. The resin used is a type V hydrophobic DES composed of menthol and decanoic acid. It is polymerized with two monomers, N-isopropylacrylamide (NIPAm) and acrylic acid (AAc), resulting in a transparent gel. The strong hydrogen bonds between DES and NIPAm and the phase separation of soft and glassy segments enable rapid photopolymerization, forming a tough gel without chemical crosslinkers. Compared to organogels, DES ionogels offer significant toughness and self-healing properties. Additionally, the gel demonstrates efficient energy dissipation and rapid self-recovery. Finally, the dielectric layer with a pyramid microstructure is fabricated using 3D printing. This structure significantly enhanced the local deformation of the dielectric layer, thereby improving the sensitivity of the sensor. This study displays a straightforward strategy for 3D printing hydrophobic DES gels, leading to the development of highly tough and self-healing materials through DLP technology.

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