Name: orientational transition in a liquid crystal triggered by the thermodynamic growth of interfacial wetting sheets
Uploaded: 2017-05-15T13:00:00
Description: Watch this Scientific Journal Video about Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets at JoVE.com

这项工作得到JSS KAKENHI授权号16H06037的支持。衷心感谢北海道大学佐佐木博士对HR-DSC的技术支持。

1.将全氟聚合物的液晶对准层制备到玻璃基板上<ol><li> 制备全氟聚合物溶液 <ol><li>通过以1：2的比例将全氟聚合物溶液（9重量％聚合物）溶解在市售溶剂中来制备1mL全氟聚合物溶液;这样可以确保0.5-1μm厚的均匀的薄膜被旋涂。 注意：请参阅材料清单，了解所用溶液和溶剂。 </li></ol></li><li> 将全氟聚合物涂覆在干净的玻璃基板上 <ol><li>通过在38或42kHz的碱性洗涤剂中?...

<ol>
	<li>Woltman, S. J., Jay, G. D., Crawford, G. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Liquid-Crystal+Materials+Find+a+New+Order+in+Biomedical+Applications.">Liquid-Crystal Materials Find a New Order in Biomedical Applications.</a> Nat. Mater. 6 (12), 929-938 (2007).</li><li>Carlton, R. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chemical+and+Biological+Sensing+Using+Liquid+Crystals.">Chemical and Biological Sensing Using Liquid Crystals.</a> Liq. Cryst.Rev. 1 (1), 29-51 (2013).</li><li>Patel, J. S., Yokoyama, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Continuous+Anchoring+Transition+in+Liquid+Crystals.">Continuous Anchoring Transition in Liquid Crystals.</a> Nature. 362, 525-527 (1993).</li><li>Senyuk, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Surface+alignment,+anchoring+transitions,+optical+properties,+and+topological+defects+in+the+nematic+phase+of+thermotropic+bent-core+liquid+crystal+A131.">Surface alignment, anchoring transitions, optical properties, and topological defects in the nematic phase of thermotropic bent-core liquid crystal A131.</a> Phys Rev E. 82 (4 Pt 1), 041711 (2010).</li><li>Bechhoefer, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Critical+Behavior+in+Anchoring+Transitions+of+Nematic+Liquid+Crystals.">Critical Behavior in Anchoring Transitions of Nematic Liquid Crystals.</a> Phys. Rev. Lett. 64 (16), 1911-1914 (1990).</li><li>Dhara, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Anchoring+Transitions+of+Transversely+Polar+Liquid-Crystal+Molecules+on+Perfluoropolymer+Surfaces.">Anchoring Transitions of Transversely Polar Liquid-Crystal Molecules on Perfluoropolymer Surfaces.</a> Phys. Rev. E. 79 (6 Pt 1), 60701 (2009).</li><li>Aya, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stepwise+heat-capacity+change+at+an+orientation+transition+in+liquid+crystals.">Stepwise heat-capacity change at an orientation transition in liquid crystals.</a> Phys. Rev. E. 86 (2), 022512 (2014).</li><li>Aya, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thermodynamically+Anchoring-Frustrated+Surface+to+Trigger+Bulk+Discontinuous+Orientational+Transition.">Thermodynamically Anchoring-Frustrated Surface to Trigger Bulk Discontinuous Orientational Transition.</a> Langmuir. 32 (41), 10545-10550 (2016).</li><li>Dhara, S., Madhusudana, N. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Physical+characterisation+of+4'-butyl-4-heptyl-bicyclohexyl-4-carbonitrile.">Physical characterisation of 4'-butyl-4-heptyl-bicyclohexyl-4-carbonitrile.</a> Phase Trans. 81 (6), 561-569 (2008).</li><li>Dierking, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Textures of Liquid Crystals. , (2003).</li><li>Perkowski, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Technical+aspects+of+dielectric+spectroscopy+measurements+of+liquid+crystals.">Technical aspects of dielectric spectroscopy measurements of liquid crystals.</a> Opto-Electronics Review. 16 (3), 271-276 (2008).</li><li>Inaba, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nano-watt+stabilized+DSC+and+ITS+applications.">Nano-watt stabilized DSC and ITS applications.</a> J Therm Anal Calorim. 79 (3), 605-613 (2005).</li><li>Leveiller, F., Boehm, C., Jacquemain, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Two-dimensional+crystal+structure+of+cadmium+arachidate+studied+by+synchrotron+X-ray+diffraction+and+reflectivity.">Two-dimensional crystal structure of cadmium arachidate studied by synchrotron X-ray diffraction and reflectivity.</a> Langmuir. 10 (3), 819-829 (1994).</li><li>de Gennes, P. G., Prost, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The Physics of Liquid Crystals (Second Edition). , (1993).</li><li>Aya, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Critical+Behavior+in+an+Electric-Field-Induced+Anchoring+Transition+in+a+Liquid+Crystal.">Critical Behavior in an Electric-Field-Induced Anchoring Transition in a Liquid Crystal.</a> Phys. Rev. E. 86 (1 Pt 1), 10701 (2012).</li><li>Avrami, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Kinetics+of+Phase+Change.+I+General+Theory.">Kinetics of Phase Change. I General Theory.</a> J. Chem. Phys. 7, 1103-1112 (1939).</li><li>Avrami, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Kinetics+of+Phase+Change.+II+Transformation-Time+Relations+for+Random+Distribution+of+Nuclei.">Kinetics of Phase Change. II Transformation-Time Relations for Random Distribution of Nuclei.</a> J. Chem. Phys. 8 (2), 212-224 (1939).</li><li>Avrami, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Granulation+Phase+Change,+and+Microstructure+Kinetics+of+Phase+Change.+III.">Granulation Phase Change, and Microstructure Kinetics of Phase Change. III.</a> J. Chem. Phys. 9, 177-184 (1941).</li><li>Sasaki, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Distinctive+Thermal+Behavior+and+Nanoscale+Phase+Separation+in+the+Heterogeneous+Liquid-+Crystal+B4+Matrix+of+Bent-Core+Molecules.">Distinctive Thermal Behavior and Nanoscale Phase Separation in the Heterogeneous Liquid- Crystal B4 Matrix of Bent-Core Molecules.</a> Phys. Rev. Lett. 107 (23), 237802 (2011).</li></ol>

使用5-μmLC单元（ 图1a和b ）拍摄的10x POM图像清楚地表明，当以一级方式温度变化时，本体LC分子的取向状态在P和V取向之间转变。这是由领域成核和生长过程标记的，其新方向与初始取向不同，为90°。冷却和加热时的转变温度分别为321.5K和325.3K。由于CCN47的双折射为〜0.02 9 ，当LC单元的厚度在5-20μm的范围内时，Schlieren纹理的可视性是好的。如果厚度小于...

近年来，人们越来越关心学习如何响应于外部刺激的表面分子的动态分子特征和结构可能影响LC状态下材料的体取向。一个例子是使用LC生物传感器作为LC1,2的新应用。为了量化检测到多少目标生物物种，重要的是要知道接触粘附目标分子的界面LC如何变化和演化，同时也检测它们如何将其性质转移到体内。 使用模型来追求这些答案，我们从具有表面分子取向和短程排序的系统开始，热力学变化。这些系统允许我们以系统的方式将表面取向和排序的变化与所得到的体积方向相关联。最近，我们发现了几个显示o的LC系统自发体积分子取向随温度变化。原则上，定向转换可以分为准二阶3,4或准一阶转换5,6,7,8。前者伴随着温度变化时的连续大分子重新取向，而后者则表现出不连续的。在本文中，我们描述了P和V定向状态之间的准一阶方向的取向转变。它通过改变温度在单向向（N）相中进行。详细情况将在代表结果和讨论中提供。 由于体积的取向变化应受表面分子取向的变化和短期的限制很明显的是，该系统可以潜在地了解表面分子取向和短程排序的热力学变化如何影响体取向。在本文中，为了理解上述问题，我们使用四种补充方法（ 即 POM，DS，HR-DSC和GI-XRD）解决了三个问题：（1）定向过渡是什么样的？ （2）取向转变是否可热？ （3）为什么和如何发生方向转变？

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
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			<td>CYTOP</td>
			<td>Asahi Glass Co. Ltd.</td>
			<td>CTX-809A</td>
			<td></td>
		</tr>
		<tr>
			<td>Solvent for CYTOP</td>
			<td>Asahi Glass Co. Ltd.</td>
			<td>CT-180 Sol.</td>
			<td></td>
		</tr>
		<tr>
			<td>Alkaline detergent</td>
			<td>Merck KGaA</td>
			<td>Extran MA01</td>
			<td></td>
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			<td>NOA61</td>
			<td>Norland Products, Inc.</td>
			<td>#37-322</td>
			<td>Purchasable from Edmund Optics</td>
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			<td>AL1254</td>
			<td>JSR Corporation</td>
			<td></td>
			<td>Planar alignment material in self-made cells</td>
		</tr>
		<tr>
			<td>4&#8217;-butyl-4-heptyl-bicyclohexyl-4-carbonitrile</td>
			<td>Nematel GmbH &#38; Co. KG</td>
			<td></td>
			<td>Custom-made</td>
		</tr>
		<tr>
			<td>UV-O3 cleaner</td>
			<td>Technovision Inc.</td>
			<td>UV-208</td>
			<td></td>
		</tr>
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			<td>Hot-stage system</td>
			<td>Mettler Toledo</td>
			<td>HS82</td>
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			<td>High-Definition Color Camera Head</td>
			<td>Nikon</td>
			<td>DS-Fi1</td>
			<td></td>
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			<td>Impedance/gain-phase analyzer</td>
			<td>Solartron Analytical</td>
			<td>1260</td>
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		<tr>
			<td>Indium Tin Oxide (ITO)-coated substrate</td>
			<td>GEOMATEC Co. Ltd.</td>
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			<td>Custom-made</td>
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	</tbody>
</table>

orientational transition in a liquid crystal triggered by the thermodynamic growth of interfacial wetting sheets

在液晶（LC）物理化学中，表面附近的分子在控制体取向方面起着很大的作用。到目前为止，主要是为了在LC显示器中实现期望的分子取向状态，已经深入研究了LC的“静态”表面性质，即所谓的表面锚定。根据经验，一旦LC的初始取向通过特定的表面处理（例如用特定取向层的摩擦或处理）“锁定”，则几乎不随温度变化。在这里，我们提出一个体现温度变化的方向转变的系统，与共识相冲突。在转换过程中，体积LC分子经历取向旋转，在高温下的平面（P）取向与低温下的垂直（V）取向之间呈90°，以一阶过渡方式。我们通过偏振光学显微镜跟踪热力学表面锚固行为（POM），介电光谱（DS），高分辨率差示扫描量热法（HR-DSC）和掠入射X射线衍射（GI-XRD），并达到合理的物理解释：转变由表面生长引发润湿片材，其在本体上局部抵抗P取向局部施加V取向。这种景观将提供一个通用的链接，说明在许多液相色谱系统中平衡体取向受到表面定向取向的影响。在我们的表征中，通过提供关于LC分子的取向的空间分布的信息，POM和DS是有利的。 HR-DSC提供关于转换的精确热力学信息的信息，由于分辨率有限，传统DSC仪器无法解决。 GI-XRD提供关于表面特异性分子取向和短程排序的信息。本文的目的是提出一种用于准备展示transi的样品的方案并演示如何通过上述方法分析体积和表面上的热力学结构变化。

在温度变化期间收集POM图像，DS数据，HR-DSC数据和GI-XRD图案，特别是在冷却和加热两者的取向过渡附近。 图1表示在冷却（加热）期间从P（V）到V（P）取向状态的取向转变的POM观察期间由POM和DS测量形成的纹理的演变。显示了基于POM观察的取向转换过程中的重新定向过程（ 图1a ）。...

Watch this Scientific Journal Video about Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets at JoVE.com

Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets

在这里，我们提出一种协议来触发液晶响应于温度的取向转变。描述了制备样品以观察转变和详细过渡演化的方法。

由界面润湿片的热力学生长触发的液晶中的定向转变

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