摻雜對聚合物分散型液晶光電特性之影響

Effect of doping on the electro - optic of polymer dispersed liquid crystal

李慧玟(Hui-Wen Li)

指導教授 ： 徐芝珊

中原大學/理學院/物理研究所/碩士(2018年)

https://doi.org/10.6840/cycu201800750

摘要

由於聚合物分散型液晶 (PDLC) 薄膜驅動電壓大，因此在生活中的應用受到了一些限制。本研究嘗試添加氧化鋅 (ZnO) 粒奈米子 (NPs) 於傳統的 PDLC 薄膜中、改用高介電異向性的液晶 HTW106700 - 100 (HTW) 及以凝膠取代聚合物，尋找出低操作電壓及高對比度的 PDLC 薄膜。
在添加氧化鋅奈米粒子的 PDLC 薄膜中，在酒精濃度為 15 wt%與氧化鋅奈米粒子為 1.5 wt% 時，我們成功的降低閾值電壓與驅動電壓，並保持了高對比度。
HTW 液晶所製作出來的 PDLC 薄膜，其最佳濃度比例為 35 wt% 的液晶 和 65 wt% 的聚合物。我們可以有效地使驅動電壓從 1.27 V/μm 降低到 0.41V/μm。並在固化光強度為 2600 μW/cm² 時，達到最高對比度。
為了降低閾值電壓與驅動電壓，我們製作出有散射效果的HTW液晶與凝膠薄膜，與傳統的 PDLC 薄膜比較，皆有明顯改善。但是其對比度還須進一步提升。

關鍵字

聚合物分散型液晶 ； 氧化鋅奈米粒子 ； 凝膠 ； 電壓

並列摘要

The polymer dispersed liquid crystal (PDLC) film has not been widely used due to its high operating voltage. We doped zinc oxide (ZnO) nanoparticles (NPs) into the conventional PDLC film, replaced typical LC E7 with high di-electric anisotropy LC (HTW106700 - 100, HTW), and exchanged polymer with gelator. Our goal is to achieve a low operating voltage and high contrast ratio of PDLC film.
We fabricated ZnO NPs in ethanol and doped them into PDLC films. We have successfully reduced threshold and driving voltages, and kept high contrast ratio when the concentration of ethanol and ZnO NPs are 15 wt% and 1.5 wt%, respectively.
When replacing LC E7 with HTW in PDLC films, the optimized concentration of HTW and polymer are 35 wt% and 65 wt%, respectively. We effectively decreased the driving voltage from 1.27 V/μm to 0.41 V/μm. The highest contrast ratio is achieved at UV curing light intensity of 2600 μW/cm².
In order to reduce the threshold and driving voltages of PDLC film, we manufactured the films with scattering property by using liquid crystal HTW and gelator. Compared with the conventional PDLC film, the operating voltage of the new films are obviously reduced. However, the contrast need to be further improved.

並列關鍵字

polymer dispersed liquid crystal (PDLC) ； zinc oxide nanoparticles (ZnO NPs) ； gelator ； voltage

參考文獻

參考文獻

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(3)吳建宏, 高分子混合液晶薄膜光電特性之研究., 交通大學影像與生醫光電研究所學位論文, 2012, p. 1–2.

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