Liquid crystals segmented

Class e, combs or e-shaped structures, with mesogens in side chains. They were developed by Shibaev and Plate and independently by Finkelmann, Ringsdorf and Wendorflf by the introduction of a flexible spacer between the backbone and the liquid crystal segment. Subsequently, Zhou, Zhu and Wen have shown that the flexible spacer is not necessary. The behavior of combs in mechanical, electric and magnetic fields was reviewed by Shibaev. We have to distinguish three subclasses, as a function of the arrangement of the side chains ... 

Linear chain polymers with repeating sequences of hard and soft segments Possibility of formation of liquid crystal polymers and thermoplastic elastomers... 

The fluorescence polarization technique is a very powerful tool for studying the fluidity and orientational order of organized assemblies (see Chapter 8) aqueous micelles, reverse micelles and microemulsions, lipid bilayers, synthetic non-ionic vesicles, liquid crystals. This technique is also very useful for probing the segmental mobility of polymers and antibody molecules. Information on the orientation of chains in solid polymers can also be obtained. 

Afterwards there appeared what has become the main application liquid crystal displays (LCDs) based on the twisted nematic (TN) mode. These are commonly used for flat panel displays (e.g., desk calculators). Thin film transistor (TFT) LCDs enabled a large number of segments (e.g., 640 x 1024) to be used and they had advantages like... 

The order and mobility of a labeled flexible alkyl spacer in the linear thermotropic polymeric nematic liquid crystal poly(2,2 -dimethyl-4,4 -dioxyazoxybenzenedodecanedioyl-dj0) (poly[oxy(3-methyl-1,4-phenylene)azoxy 2-methyl-1,4-phenylene)oxy(1,12-dioxo-1,12-dodecanediyl-d2oll) is explored with deuterium NMR. The quadrupol splittings of the spacer methylene segments in the nematic melt of the polymer are reported as a function of the temperature and are contrasted with observations on model compounds solubilized in a nematic solvent. 

Collective segmental rotation is considered to be the natural form gaining conformational entropy as the essential factor for stabilizing mesophases or liquid-crystalline structures. Despite the approximate character of our conception it should be possible to identify the significant characteristics of the intermolecular segmental arrangement in mesophases, in liquid crystals or in a polymer melt. 

Polymer Melts. When a rigid, polarizable monomer forms wither a mainchtiin polymer with flexible segments in belween or a side-chain polymer with flexible segments between the rigid segments and the flexible main chain, liquid-crystal phases are usually viable. 

Fluorinated Liquid Crystals Design of Soft Nanostructures and Increased Complexity of Self-Assembly by Perfluorinated Segments... 

Tschierske C (2011) Fluorinated liquid crystals design of soft nanostructures and increased complexity of self-assembly by perhuorinated segments. Top Curr Chem. doi 10.1007/ 128 2011 267... 

---