導電拉伸靜電紡絲奈米纖維及發光元件於智慧織物之應用

Conductive Stretchable Electrospun Nanofibers and Light-Emitting Device for Smart Textile Applications

劉欣瑜(Hsin-Yu Liu)

指導教授 ： 陳文章

國立臺灣大學/工學院/化學工程學研究所/碩士(2018年)

https://doi.org/10.6342/NTU201800451

摘要

近年來，科技日新月異，穿戴式電子裝置成為相當熱門的研究議題，藉由與醫學、通訊科技等相互結合，不僅提高生活品質，亦可提供良善的健康管理系統。而電子紡織品是將電子元件功能整合織物的技術，使產品同時具有紡織品輕薄、懸垂性及可水洗性的特性並結合電子元件的發光、發電、感測和通訊等功能，可以用來感知和反應環境的條件或刺激物的改變。
發展具可撓性、拉伸性和高導電性的電極且具有低成本和容易製造的技術對於未來的實際應用是很重要的。此外，靜電紡絲為現今最新的紡絲技術，具有許多優點，如：生產成本低、容易控制纖維相形態與大量連續式生產，可將其用於製備多功能奈米纖維。基於實驗室先前的技術，我們提出了兩種智能紡織品應用，一是藉由使用簡單和低成本的單軸靜電紡絲技術來製備兼具高導電性與拉伸性環氧樹酯/彈性體奈米纖維結合市售導電物質奈米銀線的可拉伸複合電極；二是製備具可撓性和彎曲性的聚合物電化學發光元件(PLECs)。研究細節分述如下：
第二章中，我們透過結合靜電紡絲技術製備環氧樹脂/NBR-20纖維和噴塗AgNW2.0WPU1.0的新概念來製備高導電性和可拉伸電極。環氧樹脂/NBR-20纖維的表面積大，且對奈米銀線的親和力強，可以將AgNW2.0WPU1.0吸收到所製備的纖維中，在拉伸和回復的試驗過程中，纖維內部提供了導電網絡而維持其導電性。因此，這種導電纖維可以在高達40％的機械應變下保持低電阻（小於150Ω），並可維持至少200個拉伸/回復循環而沒有明顯的電阻變化。此外，可拉伸導電纖維可以施以較小的電壓來接通LED，並使LED在人體的運動狀態下仍維持其功能。本研究表明，用AgNW2.0WPU1.0噴塗的環氧樹脂/NBR-20纖維具有很好的機械性能和高導電性，在拉伸性智能紡織品中具有潛在應用。
第三章中，我們利用發光材料Super Yellow混合聚電解質(可交聯之小分子ETPTA和具拉伸性之氟橡膠)來探討其對發光效率的影響，並於織物上製備具可撓性、可彎曲性的單層電化學發光元件，PLECs是由兩個電極夾著含有可移動離子之單一發光層組成ITO/發光層/Al之三明治結構，並利用電致發光產生可見光。製備的元件具有低操作電壓(5.0 V)，並在8 V時達到355.44 cd m-2的峰值亮度。儘管在發光過程中經過嚴重的彎曲，可撓性PLECs織物元件仍維持在發光狀態。由彎曲性能結果所示，由於ITO於彎曲狀態下會產生裂痕的缺點，亮度和發光效率會隨著彎曲曲率的增加而降低。此外，PLECs於織物應用在大氣下的穩定性不佳。
未來可望發展全織物的電子元件，不僅可以與衣服結合，也可以直接與人體連接。透過PLECs和可撓性/可拉伸導電織物的結合，織物型發光元件和利用編織方法將纖維型發光元件織成織物是未來的發展趨勢。不管是藉由將發光元件嵌入具導電紡織品或是以薄膜型的發光元件與導電織物做結合，相信未來全織物型的電子元件能發展成為下一代的穿戴式電子裝置並商業化應用於生活中。

關鍵字

靜電紡絲 ； 穿戴式電子元件 ； 拉伸導電纖維 ； 織物 ； 發光元件

並列摘要

In recent years, the topics of wearable electronic devices have been gained popularity since the rapid development of technology. The wearable electronic devices not only improve our living quality, but also provide a complete health management system by combining with the medical, communications technology, and so on. The burgeoning field of electronic textile (e-textile) is about incorporating electronic functionality into textiles [1-5], and the products also have both the characteristics of light, fabric drape and washable properties of the textiles and the functions of the luminescence[1], power generation [3], sensing [4] and communication [4-5], etc. of electronic devices, can be used to sense and react to the changes of conditions or stimuli of the environment.
The development of flexible, stretchable and highly conductive electrode with a low-cost and facile fabrication technique is critical for the practical applications in the future. Furthermore, electrospinning is the most innovative technology of spinning, with many advantages, such as low-cost production, easily controlled with the fiber morphology and a large number of continuous production, etc., can be used for the fabrication of multi-functional nanofibers.[6-7] Based on previous techniques in our lab.[6-7], we presented two smart textile applications of a stretchable electrode based on
electrospun elastomeric nanofibers/silver nanowires (AgNW) composites by using a simple, low-cost process, and polymer light-emitting electrochemical cells (PLECs) devices. The details of explorations are summarized as follows:

1. Fabricating the Highly Conductive and Stretchable Epoxy/Acrylonitrile Butadiene Rubber Blend Fiber Coated with AgNW-Waterborne Polyurethane Composites (Chapter 2): In the chapter, we have demonstrated a new concept of the fabrication of highly conductive and stretchable Epoxy/NBR-20 fiber spray-coated with AgNW2.0WPU1.0 by the combination of electrospinning and spray-coating techniques. Epoxy/NBR-20 fiber with large surface area and strong affinity to silver nanowires can absorb AgNW2.0WPU1.0 into the prepared fiber, which provides a conductive network within fiber during the stretching and recovery test. Hence, such conductive fiber can maintain low resistance (less than 150 Ω) at the mechanical strain up to 40%, and it can also sustain at least 200 stretching/release cycles without obvious changes in resistance. Furthermore, this stretchable conductive fiber can turn on the LED with a small applied voltage, and it can sustain the movement of human body. The present study suggests that the Epoxy/NBR-20 fiber spray-coated with AgNW2.0WPU1.0 possesses great mechanical property and high conductivity, which has potential applications in stretchable smart textiles.
2. Fabrication of Flexible Polymer Light-Emitting Electrochemical Cells (PLECs) for Textile Applications (Chapter 3): In the chapter, we used the light-emitting material Super Yellow (SY) mixed with polyelectrolyte of crosslinkable trimethylolpropane ethoxylate triacrylate (ETPTA) and fluoroelastomer to discuss the effects on the efficiency and fabricated the flexible single-layer PLECs on the textile. The PLECs containing the movable ions was sandwiched to constitute ITO/light-emitting layer/Al structure that generated the visible light by electroluminescence. Light emission in the device with a low turn-on voltage of 5.0 V and reaches a peak brightness of 355.44 cd m-2 at 8 V. The PLECs on textile remain emissive despite under harsh treatment of severely pinched during light emission.
It is expected that the full fabric-based design can combine with clothes, or link with the human body directly. By combining the PLECs with textile, the fabric light-emitting devices and stretchable fiber-based light-emitting devices are the development trends in the future. We expect that fiber-based light-emitting devices will be highly useful in the design of next generation electronic systems and commercialized in variety of the electronic devices.

並列關鍵字

Eelectrospinning ； Wearable electronic devices ； Stretchable conductive fibers ； Textile ； Light-emitting devices

參考文獻

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