Effect of anti-parallel and twisted alignment techniques on various propertiesof polymer stabilised liquid crystal (PSLC) films
Effect of anti-parallel and twisted alignment techniques on various propertiesof polymer stabilised liquid crystal (PSLC) films
复制标题
DOI：
10.1080/02678292.2015.1117147
复制
发表时间：
2016-03-15
期刊：
影响因子：
2.2
通讯作者：
Jain, Anuja Katariya
中科院分区：
文献类型：
--
作者：
Deshmukh, Rajendra R.;Jain, Anuja Katariya
通过将预聚物溶解在液晶中进行光聚合，制备了由聚合物网络包围的液晶（LC）域组成的复合薄膜，称为聚合物稳定液晶（PSLC）。制备了四种不同摩擦方向的复合膜，并在光聚合过程中施加和不施加电场。形态表征进行了我们使用偏光显微镜（POM）和扫描电子显微镜（SEM）显示在LC域形态和相关的聚合物网络的显着变化，在制造过程中的电场的应用。用He-Ne激光器研究了置于两个正交偏振片之间的PSLC薄膜在外加电场作用下的电光特性。结果表明，在电场作用下聚合得到的具有扭曲取向的PSLC薄膜具有较好的EO性能。使用紫外-可见分光光度计通过吸光度研究验证了EO研究获得的透射率。用精密阻抗分析仪研究了PSLC薄膜在20- 20 MHz频率范围内的介电行为。利用Debye和Cole-Cole方法对所获得的数据进行建模，以计算弛豫时间和分布参数。通过Cole-Cole模型计算的弛豫时间与响应时间一致。
Thin composite films consisting of liquid crystal (LC) domains surrounded by polymer networks, termed as polymer stabilised liquid crystals (PSLCs), were prepared by photo-polymerisation of a pre-polymer dissolved in LC. Four composite films were prepared with different rubbing directions and with and without electric field during photo-polymerisation. Morphological characterisation carried our using a polarising optical microscope (POM) and a scanning electron microscope (SEM) reveal significant changes in LC domain morphology and associated polymer networks with the application of electric field during the fabrication of the films. The electro-optic (EO) properties of PSLC films placed between two crossed polarisers were studied using a He-Ne laser under an action of externally applied electric field. It was found that the PSLC film with twisted alignment and polymerised in the presence of electric field showed better EO properties than other films. Transmittance obtained by EO studies was verified with absorbance studies using a Ultraviolet-Visible spectrophotometer. The dielectric behaviour of PSLC films in the frequency range 20-20MHz was investigated using a precision impedance analyser. The obtained data were modelled using Debye and Cole-Cole methods to calculate relaxation time and distribution parameter. The relaxation time calculated through the Cole-Cole model is in agreement with response time.