Download or read book The Design Synthesis and Characterization of Noncentrosymmetric Hydrogen Bonding Liquid Crystals written by Christopher Landorf and published by . This book was released on 2001 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design and Synthesis of Liquid Crystalline Polymer Brushes and Hydrogen Bonded Polymers written by Emma L. Conlin and published by . This book was released on 2005 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt: Our research is aimed at developing macromolecules that will lead to improved polar order in materials and new types of sensors. Our approach to developing noncentrosymmetric materials is to use hydrogen bonded liquid crystalline monomers. We report the synthesis and characterization of three molecules. Next, we investigate the presence of hydrogen bonding and the phase transitions of these molecules. We also incorporate these polymers into a liquid crystalline host. We also aim to develop polymers that may lead to the development of new sensors. Two monomers are chosen, synthesized and characterized. Solution polymerizations are performed; next, an initiator is synthesized and placed on a quartz substrate as a precursor to a liquid crystalline polymer brush. Initial attempts at brush synthesis were unsuccessful.

Download or read book Self Assembly of Homomeric Dipeptides Bisamides and Dimers written by Govindaswamy Shanker and published by LAP Lambert Academic Publishing. This book was released on 2015-08-03 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: The spontaneous interaction of molecules/molecular entities featuring distinct properties through non-covalent interactions lead to the formation of molecular assemblies called 'superstructures'. The microscopic and macroscopic properties of such superstructures generally depend on the nature of the constituent molecules. For example, shape anisometric molecules usually composed of rigid and flexible moieties tend to self-assemble and form liquid crystal (LC) phases (mesophases).In this book, Chapter I describes about LCs and applications. Chapter II comprises with the synthesis and characterization of self-assembly homomeric dipeptides and bisamides derived from naturally occurring amino acids. They are formed by covalently linking phenyl rings substituted with alkoxy tail/s through a self-complementing spacer derived from amino acid residue/s (L/D-alanine, L/D-leucine, L/D-valine). The nature of the constituent amino acid residue/s, influence their LC behavior, in particular polar columnar phase involving hydrogen (H) bonding. Chapter III describes the synthesis and thermal behavior of non-symmetric dimers and Chapter IV about bidentate ligands and their Cu/Pd(II) metal complexes

Download or read book Design Synthesis and Characterization of Columnar Discotic Bowlic Liquid Crystals written by Erman Zeng and published by . This book was released on 2001 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Making Crystals by Design written by Dario Braga and published by John Wiley & Sons. This book was released on 2007-02-27 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt: An excellent overview of the manifold aspects of modern crystal engineering. From design and preparation to spectroscopy and applications, this handbook both covers and evaluates all aspects of crystal engineering. Clearly structured, it provides an overview of the current status as seen from its various angles as well as a comparison of different techniques and applications. An essential source of high quality information for everyone working in this booming and interdisciplinary field: spectroscopists, physical and inorganic chemists as well as materials scientists working in nanotechnology and the pharmaceutical industry.

Download or read book Design Synthesis and Characterization of Cross linkable Polycatenar Liquid Crystals with Light emitting Capabilities written by Benjamin Patrick Hoag and published by . This book was released on 2000 with total page 466 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design Synthesis and Characterisation of P type and N type Semi conducting Discotic Liquid Crystals written by Andrew Wood and published by . This book was released on 1996 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Hydrogen bonded Liquid Crystal nanoparticle Nanocomposites written by Mahdi Roohnikan and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Liquid Crystal (LC) nanocomposites are a new class of smart materials that reciprocally improve the properties of the host liquid crystals and the guest nanoparticles (NPs). In this thesis, a novel approach for enhancing the colloidal stability is developed as uncontrolled aggregation of the nanoparticles remains the main barrier to applying these new materials in real-life technologies. The stability of LC-NP composites is addressed by introducing hydrogen-bonding between the NPs and the host LC. Hydrogen-bonding, an extremely important interaction in chemistry and the biological sciences, is strong, provides directionality yet is reversible in nature, making it a power-ful tool for drug design, materials chemistry and many other related fields. A systematic approach was employed that began with a baseline study consisting of dis-persing non-functionalized 3.5 nm diameter zirconium dioxide (ZrO2) NPs in a simple hydrogen-bonded aromatic acid LC, n-hexylbenzoic acid (6BA). The homogeneity of the sample and the effect on the LC orientational order was evaluated using polarized optical and fluorescence mi-croscopies and wideline 2H NMR spectroscopy. The next step was to functionalize the NP surfac-es with pendant carboxylic acid groups and vary their density with mixed ligand shells. The opti-mal miscibility was found for ZrO2 NPs with a 7:3 ratio of carboxylic acid to short alkyl spacer ligands. To eliminate the possibility of intra- and inter-particle hydrogen-bonds, since a carboxylic acid can act both as a hydrogen-bond donor and acceptor, a mechanochemical route to produce ZrO2 NPs with pendant hydrogen-bond acceptor pyridine groups was developed. To test the ef-fect of the hydrogen-bond strength, the resulting pyridine functionalized NPs were dispersed in aromatic (6BA) and aliphatic (trans-4-n-butylcyclohexanecarboxylic acid, 4-BCHA) mesogenic acids that have strong versus weaker hydrogen-bonds with pyridine. The stronger NP-LC hydro-gen-bonds between pyridine and the aromatic acid led to enhanced nematic order of the 6BA ma-trix whereas the weaker pyridine -aliphatic acid hydrogen-bonds resulted in the usual lowering of the nematic order of 4-BCHA due to dilution effects.Tuning the NP-LC interactions at the molecular level is key to producing stable NP-LC dispersions and requires molecular level characterization. Therefore, FTIR and solid-state NMR spectroscopy methods designed to characterize non-covalent interactions were applied to model hydrogen-bonded pyridine-carboxylic acid complexes consisting of 4,4'-bipyridyl and the same mesogenic aromatic and aliphatic acids used for the pyridine functionalized ZrO2 NPs. 2H NMR spectroscopy was applied to measure the nematic order parameters. The binary aliphatic-aromatic acid mixture, 6BA:4-BCHA, was also studied.Finally, a new wide temperature range hydrogen-bonded blue phase (BP) liquid crystal nanocomposite based on the previously used mesogenic acids, 6BA and 4-BCHA, and gold NPs functionalized with short chain poly (ethylene oxide) (PEO) was developed. The blue phase of the 6BA:4-BCHA mixture was moderately wide range but without thermal hysteresis. The degree of stabilization afforded by adding free PEO versus tethered to the gold NPs to the BP mixture was compared. Unlike the free PEO, the gold NPs with PEO ligand did not enhance nor disturb the BP stability, similar to previously studied gold NPs with mesogenic ligands that were shown to assemble in the BP matrices into giant cubic NP lattices." --

Download or read book Synthesis and Phase Behavior of Supramolecular Liquid Crystals written by Magdi Naoum and published by LAP Lambert Academic Publishing. This book was released on 2014-06-04 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book consists of two parts: the first part is the synthesis and characterization of model, three-ring compounds, one of the rings is a pyridine, joined together with an ester and azo groups with a terminal alkoxy group of varying chain length or a small compact polar group covering a wide range of polarity. The second part is the preparation and characterization of all possible supramolecular hydrogen-bonded complexes made from any member of the above mentioned pyridine-based compounds with two series of similarly substituted benzoic acids. In this manner, four differently substituted series of hydrogen-bonded supramolecular complexes have been prepared and investigated for their liquid crystalline behavior using different techniques.

Download or read book Liquid Crystals written by Carsten Tschierske and published by Springer Science & Business Media. This book was released on 2012-01-24 with total page 419 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fluorinated Liquid Crystals: Design of Soft Nanostructures and Increased Complexity of Self-Assembly by Perfluorinated Segments, by Carsten Tschierske Liquid Crystalline Crown Ethers, by Martin Kaller and Sabine Laschat Star-Shaped Mesogens – Hekates: The Most Basic Star Structure with Three Branches, by Matthias Lehmann DNA-Based Soft Phases, by Tommaso Bellini, Roberto Cerbino and Giuliano Zanchetta Polar and Apolar Columnar Phases Made of Bent-Core Mesogens, by N. Vaupotič, D. Pociecha and E. Gorecka Spontaneous Achiral Symmetry Breaking in Liquid Crystalline Phases, by H. Takezoe Nanoparticles in Liquid Crystals and Liquid Crystalline Nanoparticles, by Oana Stamatoiu, Javad Mirzaei, Xiang Feng and Torsten Hegmann Stimuli-Responsive Photoluminescent Liquid Crystals, by Shogo Yamane, Kana Tanabe, Yoshimitsu Sagara and Takashi Kato

Download or read book Multi Component Crystals written by Edward Tiekink and published by Walter de Gruyter GmbH & Co KG. This book was released on 2017-11-20 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this volume, contributions covering the theoretical and practical aspects of multicomponent crystals provide a timely and contemporary overview of the state-of-the art of this vital aspect of crystal engineering/materials science. With a solid foundation in fundamentals, multi-component crystals can be formed, for example, to enhance pharmaceutical properties of drugs, for the specific control of optical responses to external stimuli and to assemble molecules to allow chemical reactions that are generally intractable following conventional methods. Contents Pharmaceutical co-crystals: crystal engineering and applications Pharmaceutical multi-component crystals: improving the efficacy of anti-tuberculous agents Qualitative and quantitative crystal engineering of multi-functional co-crystals Control of photochromism in N-salicylideneaniline by crystal engineering Quinoline derivatives for multi-component crystals: principles and applications N-oxides in multi-component crystals and in bottom-up synthesis and applications Multi-component crystals and non-ambient conditions Co-crystals for solid-state reactivity and thermal expansion Solution co-crystallisation and its applications The salt-co-crystal continuum in halogen-bonded systems Large horizontal displacements of benzene-benzene stacking interactions in co-crystals Simultaneous halogen and hydrogen bonding to carbonyl and thiocarbonylfunctionality Crystal chemistry of the isomeric N,N’-bis(pyridin-n-ylmethyl)-ethanediamides, n = 2, 3 or 4 Solute・solvent interactions mediated by main group element (lone-pair)・・・π(aryl) interactions

Download or read book Pharmaceutical Co crystals Utilizing the R2 4 8 Hydrogen Bonding Motif written by Eynav Kats and published by . This book was released on 2015 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ferrocene and Ferrocenium containing Thermotropic Liquid Crystals written by Martin Schweissguth and published by . This book was released on 1997 with total page 159 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Synthesis and Characterization of Ferroelectric Liquid Crystals Designed for Nonlinear Optics written by James A. Rego and published by . This book was released on 1994 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Synthesis and Characterization of a New Chemically Bonded Liquid Crystal Stationary Phase for HPLC written by Sheela Muley and published by . This book was released on 1999 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Synthesis and Characterization of Bonded Liquid Crystal Stationary Phases for Use in High Performance Liquid Chromatography written by Mark Allen Vidensek and published by . This book was released on 1990 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design and Synthesis of Novel Liquid Crystals and Organic Semiconductors written by Kunlun Wang and published by . This book was released on 2017 with total page 567 pages. Available in PDF, EPUB and Kindle. Book excerpt: Liquid crystals have found wide applications due to their unique properties. In order to search for new nematic liquid crystal compounds with relatively low phase transition temperatures, a series of [1,2,3]-triazole-based mesogens and LC dimers were synthesized via the "Click Reaction" under mild conditions and their phase behavior will be presented. Meanwhile, hydrogen-bonded complexes mixed by benzonitrile derivatives and aromatic acetylenes are obtained and their thermal behavior examined. In order to achieve a better understanding of the influence of difluorination on the oligophenyls, a series of partially fluorinated oligomers were obtained and some of their physical properties are compared. Organic semiconductors possess many advantages compared to conventional inorganic semiconductors. Perfluorination was utilized in our molecular design for the synthesis of 1,3,5-triphenyl benzene derivatives and self-assembled crystals via nitrogen-iodine halogen bonding and the target molecules might show some interesting semicondocting properties.