We report an investigation of nematic LCs formed from miscible mixtures of 4-cyano-4’-pentylbiphenyl (5CB) and 2-(2-[2-{2-(2,3-difluoro-4-{4-(4-trans-pentylcyclohexyl)-phenyl-phenoxy)ethoxy}ethoxy]ethoxy)ethanol (EG4-LC), the latter being a mesogen with a tetra(ethylene glycol) tail. Quantitative characterization of the ordering of this LC mixture at biologically-relevant aqueous interfaces revealed that addition of EG4-LC (1–5% by weight) to 5CB causes a continuous transition in the ordering of the LC from a planar (pure 5CB) to a perpendicular (homeotropic) orientation. The homeotropic ordering is also seen in aqueous dispersions of micrometer-sized droplets of the LC mixture, which exhibit enhanced stability against coalescence. These observations and others, all of which suggest partitioning of the EG4-LC from the bulk of the LC to its aqueous interface, were complemented by measurements of the adsorption of bovine serum albumin (BSA) to the aqueous-LC interface. Whereas adsorption of BSA to the interface of a LC mixture containing 1% wt/wt of EG4-LC triggered an ordering transition, higher concentrations of EG4-LC (>2% wt/wt) prevented this ordering transition, consistent with a decrease in adsorption of BSA. This conclusion is supported by epifluorescence measurements using fluorescently labeled BSA and comparisons to LC interfaces at which EG4-containing lipids are adsorbed. Overall, these results demonstrate a general and facile approach to the design of LCs with interfaces that present biologically relevant chemical functional groups, assume well-defined orientations at aqueous interfaces, and lower non-specific protein adsorption. The bulk of the LC serves as a reservoir of EG4-LC, thus permitting easy preparation of these interfaces and the potential for spontaneous repair of the EG4-decorated interfaces during contact with biological systems.

Aligned fibrous aggregates of amide compounds having laterally fluorinated aromatic mesogens have been successfully obtained by the application of the alternating current electric field (1.0 V/microm, 1 kHz) in dodecylbenzene. In contrast, randomly entangled fibers are formed in the solvent without electric fields. For the analogous compounds without fluorine substituent, no aligned fibrous aggregates have been obtained under the electric fields. The electric field alignment of the fibers should be assisted by the fluorinated rod-shaped mesogens that exhibit negative dielectric anisotropy.

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New liquid-crystalline (LC) gels composed of a lysine-based bisurea derivative having terminal acrylate moieties and a nematic liquid crystal, 4-cyano-4 0 -pentylbiphenyl, have been prepared to develop light-scattering electrooptical materials. Randomly dispersed networks of the polymerizable fibers are obtained by self-assembly of the lysine derivative through the formation of hydrogen bonds in the isotropic phase of the nematic LC molecule. After the isotropic-nematic transition of the LC molecule occurs at 35 1C on cooling, light-scattering nematic LC gels are formed because of the formation of microphase-separated structures of fibrous solids and the liquid crystal. The fibrous structures are fixed by photopolymerization, leading to the enhancement of thermal stability. The polymerized LC gels exhibit electrooptical switching between light-scattering and transparent states with lower driving voltages than the non-polymerized LC gels. The threshold voltages of the LC gels based on the polymerizable lysine gelator are also lower than those of the LC gels containing a non-polymerizable lysine gelator. Polymer Journal (2012) 44, 594-599; doi:10.1038/pj.2012.21; published online 21 March 2012Keywords: electrooptical properties; gel; gelator; hydrogen bond; liquid crystal; photopolymerization; self-assembly INTRODUCTION Liquid crystals have been widely used as electrooptical materials because their molecular alignment can be controlled by external electric fields. 1 Their electrooptical switching properties can be tuned by the incorporation of self-assembled fibers, 2-10 organic and inorganic particles, 11,12 and dendrimers 13 into liquid crystals as well as the encapsulation or phase separation of liquid crystals in polymer matrices. 14-16 Liquid-crystalline (LC) physical gels are formed by fibrous self-assembly of small amounts of gelators (0.2-5.0 wt%) in liquid crystals. [2][3][4][5][6][7][8][9][10] In these materials, the liquid crystals and the fibrous aggregates of the gelators form microphase-separated structures. The efficient electrooptical switching and the induction of light-scattering electrooptical effects of nematic liquid crystals were achieved by the formation of finely dispersed fibers of gelators in liquid crystals. [5][6][7][8][9] The electrooptical properties of the LC physical gels were examined for twisted nematic 5,6 and light-scattering modes. 7 To enhance thermal stability of the anisotropic gels, a new type of light-scattering LC gel has been developed by self-assembly of an L-valine-based gelator having methacryloyl moieties and a room temperature nematic liquid crystal. 10 The gelator formed randomly aligned fibrous aggregates through the formation of intermolecular hydrogen bonds in the isotropic phase of LC molecules. Photopolymerization of the gelator forming the self-assembled

We are accelerating the development of materials for the solution-process OLEDs. High-performance small molecules for EML and platform polymers with reduced the molecular weight for HIL/HTL have been developed as the best practice for highresolution printed OLED panels. Further, no-diffusible pdopants have been successfully developed that are key materials for improving the performances of OLEDs produced by solution processes.