由於三維列印能夠加速製造的速度並有效地減少製程步驟，近年來已在紡織品產業呈現了的巨大潛力。紡織品的樣式、圖樣更能夠透過三維列印達到高度且快速的客製化，這在傳統的紡織產業通常需要額外的步驟與設備方能達成。此外亦可在紡織物中摻雜具導電性的材料來製成智能織物，並且提供額外功能。然而目前三維列印技術應用於紡織物的研究，仍受到列印材料的限制，尤其材料需要同時具備可列印性、穿戴舒適度以及耐久性。因此，找到一個能夠符合上述條件的材料，及一個能夠以三維列印製備紡織物的方法，是本論文研究的方向。
在本研究中，我們結合了聚乙烯醇水溶液和纖維素奈米晶體來製備可三維列印的水凝膠墨水。列印後之結構再以數個冷凍/解凍循環來引發聚乙烯醇的結晶，之後再以深共熔溶劑將水置換，最終形成以深共熔溶劑為主的離子凝膠。其中深共熔溶劑與聚乙烯醇形成了穩定且強韌的的氫鍵網絡，更富含大量的離子以提供離子導電性。額外加入的導電高分子(poly(2,3-dihydrothieno-1,4-dioxin): poly(styrene sulfonate) (PEDOT:PSS))也有效的增加了凝膠的導電性。另外，纖維素奈米晶體可有效地扮演流體流變行為的修飾劑以及膠體機械強度的增強劑。我們選擇了含有12 wt% 聚乙烯醇和4 wt% 纖維素奈米晶體來進行三維列印。三維列印的結果顯示了該墨水能夠順利列印成紡織物並具有高形狀保真度。我們的深共熔溶劑離子凝膠的抗斷裂強度可達到相當傑出的10.1 MPa，保證了此類紡織物的強度。我們接著以三維列印製備電容式感測器以偵測外加的壓力。結果顯示，此電容式感測器可做為穿戴式的智能織物，感應不同的壓力且具有高穩定性，並能夠以三維列印應對使用者的客製化需求。
總結來說，本研究結合聚乙烯醇和纖維素奈米晶體展示了一種創新的製備方法製備深共熔溶劑離子凝膠。並且運用三維列印製備紡織品且能夠組合成電容式感測器。這項研究提供了一個新穎的策略來三維列印紡織物結構的奈米複合材料。

3D printing of textiles has shown great potential due to the acceleration of fabrication and the reduction of procedure steps in the textile industry. Also, the usage of 3D printing technology enables the highly customizable designs of textiles, which are difficult in conventional textile industries. Furthermore, the incorporation of conductive materials may lead to smart textiles with additional functionalities. However, the 3D printing of textiles remains challenging because of the lack of suitable materials with printability, comfortableness during wearing, and durability. Thus, it is necessary to find new materials as well as new strategies to fabricate 3D printed textiles with high mechanical strength, conductivity, and durability.
In this study, we first prepared a 3D printable hydrogel based on poly(vinyl alcohol) (PVA) and cellulose nanocrystals (CNCs). The hydrogels then underwent several freeze-thaw cycles to induce the crystallization of PVA. The water inside the hydrogels was further replaced by the deep eutectic solvents (DESs) composed of choline chloride (ChCl) and glycerol. The solvent exchange successfully formed a stable and strong network in our ionogels compared to the original hydrogel. The DESs served as a non-volatile medium with high ionic conductivity. The introduction of poly(2,3-dihydrothieno-1,4-dioxin): poly(styrene sulfonate) (PEDOT:PSS) further increases the conductivity of our DES ionogel. The addition of CNCs provides shear-thinning behavior and sufficient yield stress for direct ink writing (DIW). The ink could be extruded and printed into a customized textile structure with high shape fidelity. The DES ionogels exhibited excellent mechanical properties with maximum stress up to 10.1 MPa compared to conventional hydrogels. We then assembled our 3D printed textile into a capacitive sensor that could sense external pressure applied by the change of capacitance. Our sensor has shown the ability to respond to various stresses. The sensor possesses high stability due to the low volatility of DES, and the 3D printed textiles could be customized to meet the user’s demand and provide comfortable wearing. These results demonstrate an innovative strategy to achieve ultra-tough, conductive, and 3D printable textile-based tactile sensors from environmentally friendly feedstock by the DIW process.

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