Dendrimer liquid crystal

Keywords Columnar mesophase Cubic mesophase Dendrimer Liquid crystal Metallomesogen Micro-segregation Organic semiconductor Perfluorinated molecule Polyphilic molecule Self-assembly... 

Abstract Applications of five-membered ring products in cyclometalation reactions for other purposes include organic electronic devices, pharmaceuticals, dye-sensitized solar cells, carbon dioxide utilizations, sensors, dendrimers, liquid crystals, resolving agents, and photosensitizers for hydrogen production. 

Fig. 9.10 Some representative cyclometalation reaction five-membered ring products are used for the other applications such as dendrimers, liquid crystals and resolving agnets...

Keywords Biopolymers Conformation Copolymers Cylindrical bmsh Dendrimer Liquid crystal NMR spectroscopy Organic electronics Polyelectrolyte Polymer Self-assembly... 

We also consider several other novel structures that are important in modern materials chemistry. These include dendrimers, liquid crystals, and fullerenes. Although polymers and these other structures are key components of organic materials chemistry, these topics alone do not encompass all of organic materials chemistry. The impact of organic chemistry on materials chemistry is far broader, including but not limited to the control of interactions between surfaces, the construction of nano-devices, and recently the creation of supramolec-ular materials that self-assemble. You should appreciate that we just cannot give a comprehensive treatment of all aspects of organic materials herein. 

In summary, much of the current research in organic materials is focused on the creation of macromolecules or interfaces with controlled properties. To control the bulk material properties, chemists must be able to control molecular weights and polydispersities, stereochemistry, sequence, and even macromolecular shape and topology. Many new kinds of materials have emerged in this effort, such as dendrimers, liquid crystals, and fullerenes. Achieving the kinds of control we are discussing often has a basis in the knowledge of the mechanisms of polymerizations, and that is the topic we now consider. 

Monomers of die type Aa B. are used in step-growth polymerization to produce a variety of polymer architectures, including stars, dendrimers, and hyperbranched polymers.26 28 The unique architecture imparts properties distinctly different from linear polymers of similar compositions. These materials are finding applications in areas such as resin modification, micelles and encapsulation, liquid crystals, pharmaceuticals, catalysis, electroluminescent devices, and analytical chemistry. 

The data presented in Figure 8 graphically illustrate the tremendous and rapid growth in interest in FOSS chemistry, especially for patented applications. This looks set to continue with current applications in areas as diverse as dendrimers, composite materials, polymers, optical materials, liquid crystal materials, atom scavengers, and cosmetics, and, no doubt, many new areas to come. These many applications derive from the symmetrical nature of the FOSS cores which comprise relatively rigid, near-tetrahedral vertices connected by more flexible siloxane bonds. The compounds are usually thermally and chemically stable and can be modified by conventional synthetic methods and are amenable to the usual characterization techniques. The recent commercial availability of a wide range of simple monomers on a multigram scale will help to advance research in the area more rapidly. 

Fig. 36. Liquid-crystal dendrimers (a) with mesogenic groups in the whole volume of a macromolecule (b) with terminal mesogenic groups.

The Tfj-symmetrical hexaaddition pattern also represents an attractive core tecton for dendrimer chemistry [26, 31, 63-67]. Examples for such dendrimers, involving a core branching multiplicity of 12, are 38 and 39 [63, 64], Addition of six mesotropic cyanobiphenyl malonate addends produced the spherical thermotropic liquid crystal 40 [65], DSC and POM investigations revealed a smectic A phase between 80 and 133 °C. Interestingly, this spherical and highly symmetrical compound gives rise to liquid crystallinity despite the absence of molecular anisotropy. 

Finally, the combination of dendrimers and organometallic entities as fundamental building blocks affords an opportunity to construct an infinite variety of organometallic starburst polymeric superstructures of nanoscopic, microscopic, and even macroscopic dimensions. These may represent a promising class of organometallic materials due to their specific properties, and potential applications as magnetic ceramic precursors, nonlinear optical materials, and liquid crystal devices in nanoscale technology. 

Keith C, Dantlgraber G, Reddy RA, Baumeister U, Prehm M, Hahn H, Lang H, Tschierske C (2007) The influence of shape and size of silyl units on the properties of bent-core liquid crystals - from dimmers via oligomers and dendrimers to polymers. J Mater Chem 17 3796-3805... 

Ferrocene-containing co-polyesters, preparation, 12, 350 Ferrocene-containing liquid crystals dendrimers, 12, 235 disubstituted ferrocenes, 12, 227 hydrogen-bonded ferrocene derivatives, 12, 234 monosubstituted ferrocenes, 12, 222 polycatenar ferrocenes, 12, 234 properties, 12, 221... 

Oct-l-ene, with dendrimers, 12, 802 Octylthiolates, liquid crystals, 12, 262 7-Octynal, silylformylation, 11, 482 ODNs, characteristics, 1, 909-910 Okaramine N, synthesis, 10, 151—152 OLED, see Organic light-emitting diodes Olefinations... 

Cook, A. G., Baumeister, U., Tschierske, C., Supramolecular dendrimers Unusual mesophases of ionic liquid crystals derived from protonation of DAB dendrimers with facial amphiphilic carboxylic acids. J. Mater. Chem. 2005, 15, 1708-1721. 

Anon-aqueous lyotropic liquid crystal with a Starburst dendrimer as a solvent. [S. E. Friberg, M. Podzimek, D. A. Tomalia, D. M. Hedstrand, Mol. Cryst. Liq. Cryst. 1988, 164, 157-165] [ 796],... 

Keywords Dendrimer Dendritic Liquid crystal Mesogen Mesophase Polypede... 

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