Aligning lyotropic liquid crystals with unconventional organic layers

Lyotropic chromonic liquid crystals (LCLC) are a kind of LCs far less known and more difficult to control than conventional thermotropic nematics. Nevertheless, LCLCs are a preferred option -often the only one- for applications where hydrophilic materials must be employed. Being water-soluble, LCLC can be used in numerous biology related devices, for example in target detection in lab-on-chip devices. However, their properties and procedures to align them are still less explored, with only a very limited number of options available, especially for homeotropic alignment. In this work, novel organic alignment layers and alignment properties have been explored for selected LCLCs. Non-conventional organic alignment layers were tested and new suitable procedures and materials for both homogeneous and homeotropic alignments have been found. Full Text: PDF ReferencesS.L. Hefinstine, O.D. Lavrentovich, C.J. Woolverton, "Lyotropic liquid crystal as a real-time detector of microbial immune complexes", Lett. Appl. Microbiol. 43, 27 (2006). CrossRef M.A. Geday, M. Ca-o-García, J.M. Escolano, E. Otón, J.M. Otón, X. Quintana, Conference on Liquid Crystals CLC'16, Poland (2016).M.A. Geday, E. Otón, J.M. Escolano, J.M. Otón, X. Quintana, Patent WO 2015193525 (2015). DirectLink Yu.A. Nastishin et al., "Optical characterization of the nematic lyotropic chromonic liquid crystals: Light absorption, birefringence, and scalar order parameter", Phys. Rev. E, 72 (4) 41711 (2005). CrossRef A. Mcguire, et al., "Orthogonal Orientation of Chromonic Liquid Crystals by Rubbed Polyamide Films", Chem. Phys. Chem. 15 (7) (2014). CrossRef J. Jeong, et al., "Homeotropic Alignment of Lyotropic Chromonic Liquid Crystals Using Noncovalent Interactions", Langmuir 30(10) 2914 (2014). CrossRef J.Y. Kim, H.-Tae Jung, "Macroscopic alignment of chromonic liquid crystals using patterned substrates", Phys. Chem. Chem. Phys. 18, 10362 (2016). CrossRef E. Otón, J.M. Escolano, X. Quintana, J.M. Otón, M.A. Geday, "Aligning lyotropic liquid crystals with silicon oxides", Liq. Cryst. 42 (8) 1069 (2015). CrossRef H.S. Park, et al., "Condensation of Self-Assembled Lyotropic Chromonic Liquid Crystal Sunset Yellow in Aqueous Solutions Crowded with Polyethylene Glycol and Doped with Salt", Langmuir 27, 4164 (2011). CrossRef H.S. Park, et al., "Self-Assembly of Lyotropic Chromonic Liquid Crystal Sunset Yellow and Effects of Ionic Additives", J. Phys. Chem. B 112, 16307 (2008). CrossRef R Caputo et al., "POLICRYPS: a liquid crystal composed nano/microstructure with a wide range of optical and electro-optical applications", J. Opt. A: Pure Appl. Opt. 11, 024017 (2009). CrossRef

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Novel Dichroic Polarizing Materials and Approaches to Large-Area Processing

MRS Proceedings ◽

10.1557/proc-508-225 ◽

1998 ◽

Vol 508 ◽

Cited By ~ 3

Author(s):

Yuri. A. Bobrov ◽

Sean M. Casey ◽

Leonid. Y. Ignatov ◽

Pavel I. Lazarev ◽

Daniel Phillips ◽

...

Keyword(s):

Liquid Crystal ◽

Liquid Crystals ◽

Liquid Crystal Display ◽

Substrate Surface ◽

Continuous Production ◽

Lyotropic Liquid Crystals ◽

Large Area ◽

Rigid Plastic ◽

Coating Materials ◽

Wide Range

AbstractWe have developed new polarizing coating materials and processes which enable the fabrication of polarizers for large-area liquid-crystal displays. The polarizing materials are novel discotic surfactants which self-assemble in aqueous solutions to provide a stable liquid-crystalline phase within a wide range of concentrations and temperatures. These lyotropic liquid crystals in an aqueous medium can be spread on a substrate surface by a variety of techniques including a knife-like doctor blade, a rolling cylinder, or a roll-to-roll method. Under the shearing force applied during deposition, the liquid crystals align on the substrate forming a dichroic polarizer. This alignment process allows continuous production of large-area polarizing films at low cost compared with the current technology that requires stretching of the films. Thin coatings can be applied to flexible plastic films, glass, or rigid plastic substrates. Direct coating of the polarizing material on glass eliminates several process steps in liquid-crystal display production since lamination of the polarizing film is no longer required. These new polarizing films have a high optical performance including a polarizing efficiency of above 98% and a dichroic ratio as high as 7.7.

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Installation for measuring the dielectric anisotropy of liquid crystals at low frequencies by the bridge method with constant displacement

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/1198/1/012006 ◽

2021 ◽

Vol 1198 (1) ◽

pp. 012006

Author(s):

S V Kalashnikov ◽

N A Romanov ◽

A V Nomoev

Keyword(s):

Liquid Crystal ◽

Liquid Crystals ◽

Internal Resistance ◽

Dielectric Anisotropy ◽

Dielectric Parameters ◽

Low Frequencies ◽

Offset Voltage ◽

Wide Range ◽

Ac Current ◽

Constant Displacement

Abstract Installation designed to measure the dielectric anisotropy in laboratory studies of liquid crystal polymer films is described. The installation operates on the principle of a balanced alternating current (AC) bridge, allowing the application of a direct external current (bias) to the liquid crystal cell. The internal resistance of the direct current (DC) source, which affects the equilibrium condition of the bridge, is compensated. The frequency of the AC current feeding the bridge and the offset voltage of the cell is regulated within a wide range, which makes it possible to study various functional dependences of the dielectric parameters of liquid crystals and their modifiers.Introduction

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Fabrication and Characterizes of TiO2 Nanomaterials Templated by Lyotropic Liquid Crystal

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.399-401.532 ◽

2011 ◽

Vol 399-401 ◽

pp. 532-537

Author(s):

Li Hua Liu ◽

Ying Bai ◽

Fu Min Wang ◽

Ning Liu

Keyword(s):

Aqueous Solution ◽

Liquid Crystal ◽

Liquid Crystals ◽

Nonionic Surfactant ◽

Formation Mechanism ◽

Lyotropic Liquid Crystals ◽

Lyotropic Liquid Crystal ◽

Micro Structure ◽

Ft Ir ◽

Rod Structures

TiO2 nanomaterials were synthesized in lyotropic liquid crystal formed by nonionic surfactant TritonX-100 and TiOSO4 aqueous solution with NH3•H2O as precipitator. The lyotropic liquid crystals were characterized by means of POM and Low-angle XRD. FT-IR, TGA, XRD, TEM were used to characterize the TiO2 samples. It was found that all the lytropic liquid crystal were in lamellar liquid crysal phase and after casting the micro-structure of the LLC phase, the TiO2 samples were self-assemble to form lamellar, sphere and rod structures. According to the characterization results, possible formation mechanism was proposed.

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A pirfenidone loaded spray dressing based on lyotropic liquid crystals for deep partial thickness burn treatment: healing promotion and scar prophylaxis

Journal of Materials Chemistry B ◽

10.1039/c9tb02929j ◽

2020 ◽

Vol 8 (13) ◽

pp. 2573-2588 ◽

Cited By ~ 1

Author(s):

Jintian Chen ◽

Hui Wang ◽

Liling Mei ◽

Bei Wang ◽

Ying Huang ◽

...

Keyword(s):

Wound Healing ◽

Liquid Crystal ◽

Liquid Crystals ◽

Lyotropic Liquid Crystals ◽

Lyotropic Liquid Crystal ◽

Burn Treatment ◽

Partial Thickness ◽

Partial Thickness Burn

This study develops a HA combined lyotropic liquid crystal based spray dressing loaded with pirfenidone for wound healing and scar prophylaxis.

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Liquid crystal/glass interface effects on the orientation of lyotropic liquid crystals in magnetic fields

Canadian Journal of Chemistry ◽

10.1139/v78-356 ◽

1978 ◽

Vol 56 (16) ◽

pp. 2178-2183 ◽

Cited By ~ 30

Author(s):

Fred Y. Fujiwara ◽

Leonard W. Reeves

Keyword(s):

Magnetic Field ◽

Liquid Crystal ◽

Liquid Crystals ◽

Cylindrical Tube ◽

Lyotropic Liquid Crystals ◽

Crystal Glass ◽

Type I ◽

Type Ii ◽

Glass Interface ◽

Interface Effects

Lyotropic mesophases of both positive (type I) and negative (type II) diamagnetic anisotropy have been prepared. The deuterium magnetic resonance signal from D2O in the sample bas been studied during the process of orientation in a magnetic field. A type II mesophase oriented by a magnetic field in a cylindrical tube perpendicular to the lines of force does not achieve a uniform distribution of directors in a plane perpendicular to the field. The re orientation of a type I mesophase after an initial displacement of the director at an angle to the field has been studied. Previous equations derived for thermotropic liquid crystals are applicable but the velocity of re-orientation was found to be an inverse function of the radius, for nmr tubes of less than 4 mm in diameter, indicating that liquid crystal/glass interface effects are important.

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The influence of orienting layers on blue phase liquid crystals in rectangular geometries

Photonics Letters of Poland ◽

10.4302/plp.v10i4.868 ◽

2018 ◽

Vol 10 (4) ◽

pp. 100 ◽

Cited By ~ 2

Author(s):

Marzena Maria Sala-Tefelska ◽

Kamil Orzechowski ◽

Filip A. Sala ◽

Tomasz R. Woliński ◽

Olga Strzeżysz ◽

...

Keyword(s):

Liquid Crystal ◽

Liquid Crystals ◽

Electric Field ◽

Low Voltage ◽

Bragg Reflection ◽

Phase Liquid ◽

Blue Phase ◽

Blue Phases ◽

Alignment Layers ◽

Polymer Stabilized

In this paper, the influence of homeotropic and homogeneous orienting layers is presented in a cell filled with chiral nematic liquid crystals stabilized in a blue phase. The change of selective Bragg reflection from red to blue light was observed for homogeneous layers in rectangular geometries. The growth of blue phase crystals domains in a glass cell as well an influence of temperature and the electric field on such a structure, are also presented. Full Text: PDF ReferencesF. Reinitzer, Beitrage zur Kenntniss des Cholestherins, Monatsh Chem. 9, 421-441, (1888). CrossRef J. Yan, M. Jiao, L. Rao, and S.-T. Wu, "Direct measurement of electric-field-induced birefringence in a polymer-stabilized blue-phase liquid crystal composite", Opt. Express 18, 11450-11455 (2010) CrossRef Y. Chen, D. Xu, S.-T. Wu, S.-i. Yamamoto, Y. Haseba, "A low voltage and submillisecond-response polymer-stabilized blue phase liquid crystal", Appl. Phys. Lett. 102, 141116 (2013) CrossRef Y. Huang, H. Chen, G. Tan, H. Tobata, S. Yamamoto, E. Okabe, Y.-F. Lan, C.-Y. Tsai, and S.-T. Wu, "Optimized blue-phase liquid crystal for field-sequential-color displays", Opt. Mater. Express 7, 641-650 (2017) CrossRef V. Sridurai, M. Mathews, C. V. Yelamaggad, G. G. Nair, "Electrically Tunable Soft Photonic Gel Formed by Blue Phase Liquid Crystal for Switchable Color-Reflecting Mirror", ACS Appl. Mater. Interfaces, 9 (45), 39569-39575 (2017) CrossRef E. Oton, E. Netter, T. Nakano, Y. D.-Katayama, F. Inoue, "Monodomain Blue Phase Liquid Crystal Layers for Phase Modulation", Sci. Rep. vol.7, 44575 (2017) CrossRef Q. Liu, D. Luo, X. Zhang, S. Li, Z. Tian, "Refractive index and absorption coefficient of blue phase liquid crystal in terahertz band", Liq. Cryst., Vol. 44, No. 2, pp. 348-354 (2017) CrossRef Y. Li, Y. Liu, Q. Li, S.-T. Wu, "Polarization independent blue-phase liquid crystal cylindrical lens with a resistive film", Appl. Opt., Vol. 51, No. 14, pp. 2568-2572 (2012) CrossRef M. M. Sala-Tefelska, K. Orzechowski M. Sierakowski, A. Siarkowska, T.R. Woliński, O. Strzeżysz, P. Kula, "Influence of cylindrical geometry and alignment layers on the growth process and selective reflection of blue phase domains", Opt. Mater. 75, 211-215, (2018) CrossRef H. Claus, O. Willekens, O. Chojnowska, R. Dąbrowski, J. Beeckman, K. Neyts, "Inducing monodomain blue phase liquid crystals by long-lasting voltage application during temperature variation", Liq. Cryst. 43 (5), 688-693, (2016) CrossRef M. Takahashi, T. Ohkawa, H. Yoshida, J. Fukuda, H. Kikuchi, M. Ozaki, "Orientation of liquid crystalline blue phases on unidirectionally orienting surfaces", J. Phys. D: Appl. Phys. 51 (10), 104003 (2018) CrossRef P. Joshi, X. Shang, J. De Smet, E. Islamai, D. Cuypers, G. Van Steenberge, S. Van Vlierberghe, P. Dubruel, H. De Smet, "On the effect of alignment layers on blue phase liquid crystals", Appl. Phys. Lett. 106, 101105 (2015) CrossRef K. Orzechowski, M.W. Sierakowski, M. Sala-Tefelska, P. Joshi, T.R. Woliński, H.D. Smet, "Polarization properties of cubic blue phases of a cholesteric liquid crystal", Opt. Mater. 69, 259-264 (2017) CrossRef P.-J. Chen, M. Chen, S.-Y. Ni, H.-S. Chen, Y.-H. Lin, "Influence of alignment layers on crystal growth of polymer-stabilized blue phase liquid crystals", pt. Mater. Express 6, 1003-1010 (2016) CrossRef CrossRef

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Light-Controlled Lyotropic Liquid Crystallinity of Polyaspartates

10.26434/chemrxiv.13643126.v1 ◽

2021 ◽

Author(s):

Max Hirschmann ◽

Christina M. Thiele

Keyword(s):

Liquid Crystal ◽

Liquid Crystals ◽

Morphological Changes ◽

Thermal Relaxation ◽

Lyotropic Liquid Crystals ◽

Solution Viscosity ◽

Layer By Layer ◽

Nano Technology ◽

Biological Responses ◽

Photo Alignment

In nature, proteins like rhodopsin act as transducer for photo-chemical reactions causing biological responses (e.g. enabling vision). The underlying concept – a photo-induced conformational change of the protein as amplifier of the photo-responsive moiety – can also be adopted by synthetical polymers or foldamers that have the propensity to form ordered secondary structures (e.g. polypeptides). An alternative approach to amplify photo-chemical responses is their incorporation into liquid crystals. With only a few exceptions, photo-insensitive liquid crystals are doped with dyes that favour disorder upon irradiation. In theory, photo-responsive polypeptides, capable of forming lyotropic liquid crystals, could exploit both amplification approaches but, in practice, their photo-responsivity is hampered by the reduced mobility of polypeptides in concentrated solutions. Here we show that the E/Z photo-isomerisation of an azobenzene containing polyaspartate initiates a helix-coil backbone transition, which reversibly alters the polypeptide solution from anisotropic to isotropic. In contrast to other photo-responsible polymers14, in which thermal relaxation to the more stable photo-isomer is quite fast, both photo-isomers are thermally stable and interconvertible by visible light in a single solvent. Local irradiation and magnetic fields lead to spatial resolution and unidirectional architectures of the liquid crystal, respectively. Our results demonstrate that photo-isomerisation on a molecular level is amplified in three stages via intra- and intermolecular interactions to yield a unidirectional, chiral liquid crystal. We believe, the morphological changes of the liquid crystal induced by light will facilitate a multitude of applications, like photo-alignment or the photo-control of solution viscosity and anisotropic diffusion. When incorporated into layer-by-layer architectures the polymer could find application in biomedicine and the spatial and temporal resolution could be exploited in nano-technology.

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Novel Trends in Lyotropic Liquid Crystals

Crystals ◽

10.3390/cryst10070604 ◽

2020 ◽

Vol 10 (7) ◽

pp. 604 ◽

Cited By ~ 1

Author(s):

Ingo Dierking ◽

Antônio Martins Figueiredo Neto

Keyword(s):

Graphene Oxide ◽

Liquid Crystal ◽

Liquid Crystals ◽

Soft Matter ◽

Anisotropic Materials ◽

Lyotropic Liquid Crystals ◽

Electro Optic ◽

Thermotropic Liquid Crystals ◽

Active Liquid ◽

Biological Liquid

We introduce and shortly summarize a variety of more recent aspects of lyotropic liquid crystals (LLCs), which have drawn the attention of the liquid crystal and soft matter community and have recently led to an increasing number of groups studying this fascinating class of materials, alongside their normal activities in thermotopic LCs. The diversity of topics ranges from amphiphilic to inorganic liquid crystals, clays and biological liquid crystals, such as viruses, cellulose or DNA, to strongly anisotropic materials such as nanotubes, nanowires or graphene oxide dispersed in isotropic solvents. We conclude our admittedly somewhat subjective overview with materials exhibiting some fascinating properties, such as chromonics, ferroelectric lyotropics and active liquid crystals and living lyotropics, before we point out some possible and emerging applications of a class of materials that has long been standing in the shadow of the well-known applications of thermotropic liquid crystals, namely displays and electro-optic devices.

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Lyotropic Liquid Crystals from Colloidal Suspensions of Graphene Oxide

Crystals ◽

10.3390/cryst9090455 ◽

2019 ◽

Vol 9 (9) ◽

pp. 455 ◽

Cited By ~ 1

Author(s):

Adam P. Draude ◽

Ingo Dierking

Keyword(s):

Carbon Nanotubes ◽

Graphene Oxide ◽

Liquid Crystal ◽

Liquid Crystals ◽

Liquid Crystalline ◽

Colloidal Particles ◽

Colloidal Suspensions ◽

Lyotropic Liquid Crystals ◽

Nanoscience And Nanotechnology ◽

And Behavior

Lyotropic liquid crystals from colloidal particles have been known for more than a century, but have attracted a revived interest over the last few years. This is due to the developments in nanoscience and nanotechnology, where the liquid crystal order can be exploited to orient and reorient the anisotropic colloids, thus enabling, increasing and switching the preferential properties of the nanoparticles. In particular, carbon-based colloids like carbon nanotubes and graphene/graphene–oxide have increasingly been studied with respect to their lyotropic liquid crystalline properties over the recent years. We critically review aspects of lyotropic graphene oxide liquid crystal with respect to properties and behavior which seem to be generally established, but also discuss those effects that are largely unfamiliar so far, or as of yet of controversial experimental or theoretical outcome.

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