Effects of the composition and nematic–isotropic phase transition on the electro‐optical responses of unaligned polymer‐dispersed liquid crystals. I. Composites of poly(methyl methacrylate) and E8
Effects of the composition and nematic–isotropic phase transition on the electro‐optical responses of unaligned polymer‐dispersed liquid crystals. I. Composites of poly(methyl methacrylate) and E8
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DOI：
10.1002/app.27906
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发表时间：
2008-06
影响因子：
3
通讯作者：
R. Deshmukh;M. Malik
中科院分区：
文献类型：
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作者：
R. Deshmukh;M. Malik
采用三氯甲烷溶液浇铸法制备了聚甲基丙烯酸甲酯(PMMA)与向列型液晶(LC)E8的复合膜。研究了不同组成的PMMA/E8(10-80wt%E8)的电光性能。以He-Ne激光器(λ=632.8 nm)为光源，在70和80wt%两个特定的LC水平上，测量了温度、电压和外加电场频率对薄膜光学透过率的影响。扫描电子显微镜观察表明，由于相分离，在PMMA中形成了较大的E8液滴，且随着E8含量的增加，E8液滴的均匀分布增加。结果从聚集结构、界面相互作用、LC负载量和LC在聚合物基质中的溶解度等方面进行了解释。结果表明，在实验条件下，通过选择合适的LC负载量，可以连续控制输出到理想的水平，以制备响应时间仅为几毫秒量级的聚合物分散的LC电光活性复合膜。#2008威利期刊公司《应用理工学院学报》，2008
Composite films composed of poly(methyl methacrylate) (PMMA) and the nematic-type liquid crystal (LC) E8 were prepared by solution casting in chloroform. The electro-optical performance characteristics were studied for a wide range of PMMA/E8 compositions (10–80 wt % E8). At two specific levels of LC (70 and 80 wt %), the effects of temperature, voltage, and frequency of the applied electric field on the optical transmittance of films were extensively measured with a He–Ne laser (λ = 632.8 nm) as a light source. Scanning electron microscopy observations showed the formation of large E8 droplets in PMMA due to phase separation, and the homogeneous distribution increased with increasing E8 content. The results were interpreted in terms of aggregation structure, interfacial interaction, LC loading, and the solubility of LC in the polymer matrix. The results obtained indicate that under the experimental conditions imposed, the output could be continuously controlled to the desired level by the selection of a suitable loading of LC to prepare polymer-dispersed LC electro-optical active composite films with response times on the order of only a few milliseconds. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008