以金屬有機骨架回復劣化液晶之電學特性

Recovery of the Electrical Properties of a Deteriorated Liquid Crystal by Metal-Organic Frameworks

黃成鼎(Cheng-Ting Huang)

指導教授 ： 李偉 ； 徐芝珊

中原大學/理學院/應用物理研究所/碩士(2013年)

https://doi.org/10.6840/cycu201300684

摘要

在製造液晶面板的生產線上，剩餘或過量的液晶材料因為曾暴露於空氣與接觸過其它物體，導致被污染的可能性增加，所以此類液晶通常會被當作劣化的液晶材料而被淘汰與丟棄，造成難以避免的浪費。因此，本論文試圖利用金屬有機骨架（metal-organic frameworks, MOFs）材料對性質劣化的液晶材料進行純化處理，期待能回復液晶電學特性並達到可以再次利用的目的。純化方法是將金屬有機骨架材料浸泡於劣化液晶中，藉由吸附水氣與離子的特性來降低液晶材料內的雜質離子含量，達到減弱離子效應造成的負面影響。
實驗結果顯示，經過純化處理的劣化液晶，其離子屏蔽效應與導電率都有明顯地下降，隨金屬有機骨架料的劑量增加，液晶內的可移動離子濃度也越來越低；而電壓保持率隨純化處理時間越長，提昇的幅度也越高，由雜質陽離子濃度分布的分析知道金屬有機骨架材料確實可以吸附液晶內的雜質陽離子。此外，附加攪拌處理能有效的提高純化效率，再者，比較各實驗結果可發現金屬有機骨架材料的飽和吸水率對於純化效果有相當直接的影響。總體來說，以金屬有機骨架材料回復劣化液晶電學特性，是相當有潛力與值得繼續探討的純化研究之議題。

關鍵字

金屬有機骨架 ； 液晶

並列摘要

Liquid crystals (LC) leftover from the panel production line is highly contaminated by the pollution from the air and other objects. Once the LC is considered to have been contaminated or degraded, it has to be eliminated and discarded for the sake of the quality of LC display (LCD). This action results in raising the cost and is not environment friendly. This work conducts a series of experiments of purifications which recovers the electrical properties of degraded liquid crystal materials via a soaking treatment of metal organic frameworks (MOFs) porous materials.
The results indicate that the electrical properties such as electric conductivity, ionic screen effect and voltage holding ratio, of the degraded LC are improved by MOFs treatment due to the adsorption of moisture and impurity ions. The results of the metal cation concentration measurement confirm that the MOFs can also adsorb the metal cation in the LC. Furthermore, the water adsorption capacity of the MOFs is positively related to the efficiency of purification. This investigation made advancement on recycling the degraded LC with simple treatments of MOFs.

並列關鍵字

liquid crystal ； metal-organic frameworks

參考文獻

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