柔性電子憑藉其獨特的靈活性，該技術相關應用已可見於許多產品，包括顯示器、有機發光二極體、 太陽能電池板、電子皮膚貼片 等，近年來 柔性電子之專利申請量以平均 15.7 %的成長速度逐年提升， 專利分析顯示其著重於改善製造方法，可撓式 透明 導電薄膜為柔性電子產品之關鍵材料，奈米銀線為目前可量產應用的導電材料 。 本文針對奈米銀線原料之分離純化進行研究，銀奈米線原料可加工製成可撓式透明導電薄膜，銀線純度會大幅影響導電膜光電特性，因此 值得深入研究。

本研究分成四個部分， 第一部分 為初步分離階段，目的是將銀奈米線原液中之大顆粒去除，方法為多元 醇 法合成之銀奈米線放入萃盤堆疊的沈降槽，利用重力自然沉降數天，以將銀奈米線懸在液相。第二部分為奈米線與奈米顆粒分離，目的是將銀奈米顆粒去除，將第一階段沉降後流出物導入不同沈降槽中，將溶液中之銀奈米線沈澱於萃盤上。本研究探討分離參數，如沉降天數、反應劑濃度等對於銀奈米線純化之影響。第三部分為廢溶液中銀回收，本研究利用連續式離心機，可將廢溶液中的銀固體分離取出，使處理廢液成本降低，並探討如轉速、時間等參數之影響。第四部份為應用高分子管式膜純化並增濃銀奈米線溶液，利用管式膜特性將銀溶液中銀奈米顆粒去除，同時達到增 濃並純化的製程。

本研究利用自然沉降萃取槽成功分離銀奈米顆粒及銀奈米線，達到純化之效果且產率高達 60%以上，而應用蝶式離心機可以將廢液中 99%以上的銀回收，且應用管式膜成功增濃銀奈米線溶液，對於後續產品純化以及溶液中銀回收應用上具發展潛力。

The flexible electronics with wide practicability, so this technology has been applied in various industry fields, including electronic displays, organic light-emitting diodes, thin-film solar panels, and electronic skin patches, etc. The filed patents for flexible electronics are increased with an average growth rate of 15.7% recently. The analysis result of these patents indicates the tendency is focused on the improvement of manufacturing methods. Flexible transparent conductive films are the key material of flexible electronic products, and the silver nanowire can be mass production and used as conductive coating. The purity of silver wire plays an important role in the photoelectric characteristics of conductive films. Thus, the separation and purification of silver nanowire were investigated in this work.

There were four parts in this study. The first part was the preliminary separation stage, where the large silver particles was removed from the silver nanowire solution. The silver nanowire solution, synthesized via polyol method, was placed in the settling tank equipped plenty of extraction trays. The large particles were gradually deposited on trays due to their large density during several days, resulting in the suspension of silver nanowires in the liquid phase. The second procedure was to separate nanowires and nanoparticles further. The mixture of silver nanowire and nanoparticle from the first stage of sedimentation was conducted into second settling tanks. The silver nanowires were deposited on the extraction trays contrarily, and the nanoparticles can be drained out with liquid flow. The effects of settling days and reagent concentration on separation rate and purity of product were studied in detail. The recovery of silver particle in waste solution was evaluated in the third section. A continuous centrifuge was used to capture the silver solids in the waste solution, which reduced the treatment cost of liquid waste. The major parameters for this separation step were operation time and rotation speed. Finally, the polymer tube membrane was applied to purify and concentrate the silver nanowire solution. The nanoparticles and solvent were penetrated from inside to outside, so the concentration and purity of silver wire could be improved at the same time.

In conclusion, the qualified silver nanowires solution with 60% of yield rate were successfully achieved in the natural sedimentation procedures. 99% of the silver solid in the liquid waste was able to be recovered with using a continuous centrifuge. The polymer tube membranes showed the feasibility in the subsequent product purification and silver recovery in the future.

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