Orthogonal liquid crystal polymers

Class jS, orthogonal liquid crystal polymers. As class a, they also contain liquid crystal groups in the main chain however, these groups are here approximately perpendicular to the backbone. Two kinds of such polymers are obtained by Ringsdorf and coworkers, based on the siloxane chain and also polyesters. In this second series it appears that crystalline and liquid crystalline regions coexist until isotropization at the clearing temperature occurs. 

We recall that the first liquid crystals, which were monomer LCs (MLCs), were discovered by Friedrich Reinitzer in 1888 [23] while the first book about them appeared 20 years later [24]. While much has been done in the last century, both MLCs and PLCs remain fascinating object to study and to apply. We have seen several results of MD simulations of PLCs. A tacit assumption was made above all along the simulated PLCs were all longitudinal, that is with LC sequences in the main chain and oriented along the chain backbone. Various other classes of PLCs have been synthesized by chemists [18,25,26]. These include orthogonal, with the LC sequences also in the backbone but perpendicular to it. There exist as well various kinds of combs, and even polymers with three-dimensional LC units. MD simulations should be able to elucidate mechanical behavior of such PLCs as well. This is particularly noteworthy since the promise made in section 15.1 to provide simulation results unobtainable from experiments appears to have been kept. 

Classify polymer liquid crystals in fuiKtion of their chemical shuctures. Compare viscosities of longitudinal and orthogonal polymer liquid crystals. 

Figure 2.21 Orthogonal orientations for solvation of a rod-like polymer(MEH-PPV) in a smectic liquid crystal (8CB). Schematic illustration ofthe nematic (a) and ideal smectic (b) phase P histograms measured with...

The 85th Edition includes updates and expansions of several tables, such as Aqueous Solubility of Organic Compounds, Thermal Conductivity of Liquids, and Table of the Isotopes. A new table on Azeotropic Data for Binary Mixtures has been added, as well as tables on Index of Refraction of Inorganic Crystals and Critical Solution Temperatures of Polymer Solutions. In response to user requests, several topics such as Coefficient of Friction and Miscibility of Organic Solvents have been restored to the Handbook. The latest recommended values of the Fundamental Physical Constants, released in December 2003, are included in this edition. Finally, the Appendix on Mathematical Tables has been revised by Dr. Daniel Zwillinger, editor of the CRC Standard Mathematical Tables and Formulae it includes new information on factorials, Clebsch-Gordan coefficients, orthogonal polynomials, statistical formulas, and other topics. 

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