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Density, viscosity, and refractive index for the binary systems water + 2-butoxyethanol and water + 2-(2-butoxyethoxy)ethanol have been measured at the temperatures ranging from (283.15 to 323.15) K at atmospheric pressure. The excess molar volume and deviations of viscosity and refractive index from a mole fraction average of these binary mixtures were correlated by the Redlich−Kister equation.

Liquid crystal alignment was investigated on the microgrooved silica surfaces modified by organosilanes. In this study, the microgrooved silica surfaces were fabricated by the soft embossing method...

In this study, the soft embossing method is proposed to fabricate periodical microgrooved structure on polyimide surfaces. These microgrooved polyimide surfaces are assembled to form liquid-crystal cells. It is found that the director of liquid crystals uniformly aligns along the groove direction even when the groove width is as high as 3 microm. The anchoring energy of these microgrooved polyimide surfaces is higher than that of the typical rubbed surfaces. The pretilt angle of liquid crystals is adjusted by tuning the surface polarity of the polyimide alignment layer, which is identified by the advancing contact angle of water. The surface polarity of polyimide alignment layers is manipulated by simply mixing two kinds of polyimide: a more hydrophilic one and a more hydrophobic one. It is found that the pretilt angle of liquid crystals increases along with the advancing contact angle of water on the alignment layer under the condition of a fixed surface topography.

Self-assembled monolayers of carboxylic acids on a silver surface underwent a reversible reorganization process to form discrete clusters of hydrogen-bonded free acids upon exposing the monolayer assembly to H2S vapor. The clusters had a wide range of sizes, from nearly one micrometer to tens of nanometers or smaller. Restoration of the monolayer film from the clusters, driven by the reaction between the carboxylic acid molecules and the basic surface sites, proceeded on the surface through surface migration of molecules in the clusters. The process was real-time imaged by tapping mode atomic force microscopy.

In this work, we present the liquid−liquid equilibrium data of a ternary system, water + octane + diethylene glycol monobutyl ether, at 283.15 K, 293.15 K, and 303.15 K under atmospheric pressure. The experimental data were correlated with the UNIQUAC model, and a good agreement was obtained.

Liquid−liquid equilibria of a ternary system water + 2-methyl-2-butanol + diethylene glycol monobutyl ether were measured at 293.15 K, 303.15 K, and 313.15 K under atmospheric pressure. The experimental equilibrium data were correlated with the UNIQUAC model, and a good agreement was obtained.

The square-wave grating silica surfaces are fabricated by soft embossing silica sol-gel precursor on glass substrates with an elastomeric polydimethylsiloxane mold. The patterned silica surface could induce the planar alignment of liquid crystal 4-n-pentyl-4′-cyanobiphenyl (5CB) along the direction of microgrooves but with no pretilt angle. The pretilt angle of 5CBs is adjusted from 0° to 90° by the further deposition of organosilane self-assembled monolayers with different functional end-groups on the patterned silica surfaces.