Mesomorphic layer

Kidman, H.S. and van Steen, RJ.E, Rheological investigation of mesomorphic layers formed at the liquid/liquid interface, J. Physique 40, C3-447, 1979b. 

After the formation of the mesomorphic layer, it starts to spontaneously thicken up to a certain point when a crystal block is formed via a first-order transition. In the later stage of crystallization, the energy of the fold surface is reduced (cf. Figure 11). 

Tam and surface free energies. The line Tam refers to the transition between the melt and the mesomorphic layer and is correspondingly described by... 

Organized Langmuir films and poly layers of mesomorph cyclolinear polysilox-anes 98MI35. 

The mesomorphous phase, also called an intermediate phase or a mesophase, is formed by molecules occurring in surface layers of the crystallites. It can be assumed that the mesophase is made up largely by regularly adjacent reentry folds. However, it cannot be excluded that the mesophase is also composed of some irregular chain folds, which are characterized by a long length and run near the crystal face in the direction perpendicular to the microfibril axis. 

Crystalline forms presenting large amounts of disorder of the kind (ii) or (iii) are generally called mesomorphic modifications (Section 3.6), in analogy with the ordered liquids (smectic and nematic). In these cases the lack of periodicities in one or two dimensions (e.g., along the chain axes or along the directions normal to the chain axes) prevents the definition of a unit cell. Typical features in the X-ray diffraction patterns of mesomorphic forms are diffuse halos on the equator or on the layer lines depending on the kind of disorder present. 

Mesomorphic forms characterized by conformationally ordered polymer chains packed in lattices with different kinds of lateral disorder have been described for various isotactic and syndiotactic polymers. For instance, for iPP,706 sPP,201 sPS,202 syndiotactic poly(p-methylstyrene) (sPPMS),203 and syndiotactic poly(m -methylstyrene),204 mesomorphic forms have been found. In all of these cases the X-ray fiber diffraction patterns show diffraction confined in well-defined layer lines, indicating order in the conformation of the chains, but broad reflections and diffuse haloes on the equator and on the other layer lines, indicating the presence of disorder in the arrangement of the chain axes as well as the absence of long-range lateral correlations between the chains. 

An exception to the rule that lowering the Iciiiperaiure cutises transitions to phases with increased order sometimes occurs for polar compounds w hich form the smectic l. phase (a layered structure formed by molecular dimers). Decreasing the temperature cutises u transition front nematic to smectic. 1,.,. but a further lowering of the temperature produces J transition back to the nematic phase tcalled the reentrant nematic phase). Electric or magnetic fields also may induce mesomorphic phase transitions. 

As pointed out in Chapter 1, supramolecular chemistry comprises two broad, partially overlapping areas covering on the one hand the oligomolecular supermolecules and, on the other, the supramolecular assemblies, extended polymolecular arrays presenting a more or less well-defined microscopic organisation and macroscopic features depending on their nature (layers, films, membranes, vesicles, micelles, microemulsions, gels, mesomorphic phases, solid state species, etc.). 

Deschenaux et al. were likely first to use this combination of mesomorphic cyanobiphenyl-based dendrons, both mixed and homogeneous monolayer fashion, on gold nanoparticles with average sizes of 1.2 or 1.7 nm in diameter, but found no liquid crystal phase formation in the bulk aside from the pattern formation on TEM grids resembling a layer-like organization of the gold nanoparticles [546],... 

The present review is mainly concerned with the preparation and functionalization of micro compositional materials with cellulosic polysaccharides as the principal component, including four major categories graft copolymers, miscible or compatible polymer blends and networks, polysaccharide/inorganic nanohybrids, and mesomorphic ordered systems. Ultrathin layers of cellulosic... 

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