With liquid-crystalline order

Baird, D. G. The rheology of polymers with liquid-crystalline order, in Rheology, Vol. 3, Applications (ed.) Astarita, G., Mannicci, G., Nicolais, L., p. 647, New York, Plenum, 1980... 

Hydrophobically modified polybetaines combine the behavior of zwitterions and amphiphilic polymers. Due to the superposition of repulsive hydrophobic and attractive ionic interactions, they favor the formation of self-organized and (micro)phase-separated systems in solution, at interfaces as well as in the bulk phase. Thus, glasses with liquid-crystalline order, lyotropic mesophases, vesicles, monolayers, and micelles are formed. Particular efforts have been dedicated to hydrophobically modified polyphosphobetaines, as they can be considered as polymeric lipids [5,101,225-228]. One can emphasize that much of the research on polymeric phospholipids was not particularly focused on the betaine behavior, but rather on the understanding of the Upid membrane, and on biomimicking. So, often much was learnt about biology and the life sciences, but little on polybetaines as such. 

The values of and r=d2 ld2i predicted by the different theoretical models and the resulting evaluation of SHG enhancement with liquid crystalline axial order are given in Table 24 for polyacrylate 41 PA 3 and copolyether 45 (x=0.8). The data in Table 24 confirm that it is possible to gain in net polar ordering by starting from a liquid-crystalline system. The enhancement of the NLO performance with liquid-crystalline order is by a factor of 2.3-3.3 in qualitative agreement with the SKS [156] and MS VP [157-159] model results. It should be noted, however, that the measured order parameters (P2) are lower than the calculated... 

FIGURE 7.4 Photoinduced phase transition occurs in PLCP materials upon light irradiation since usually the trans-azohenzene acts as a rod-like mesogen while the bent cw-azobenzene usually has a soft shape, not compatible with liquid crystalline order. 

D.G. Baird, "Rheology of Polymers with Liquid Crystalline Order," in Liquid Crystalline Order in Polymers, Academic, New York, 1978, pp. 237-259. 

Copolymers of mesogenic with non-mesogenic vinyl monomers provide the opportunity to diversify the properties of polymers with liquid crystalline order. 

Vlachos, P, et al. Charge-transport in crystalline oiganic semiconductors with liquid crystalline order Chem. Common. 23, 2921—2923 (2005)... 

In conclusion, the different thermal histories imposed to PTEB have a minor effect on the /3 and y relaxations, while the a. transition is greatly dependent on the annealing of the samples, being considerably more intense and narrower for the specimen freshly quenched from the melt, which exhibits only a liquid crystalline order. The increase of the storage modulus produced by the aging process confirms the dynamic mechanical results obtained for PDEB [24], a polyester of the same series, as well as the micro-hardness increase [22] (a direct consequence of the modulus rise) with the aging time. 

Similar to the sitnation with DNA structures formed under osmotic stress, DNA strands in cation-condensed bundles were found to be hexagonally packed and to possess liqnid crystalline order. For example, spermine and spermidine-condensed samples were fonnd to contain a cholesteric phase [70]. Surprisingly, DNA condensed with (Co(NH3)6) failed to exhibit a liquid crystalline ordering [47]. 

Rod-like micelles of surfactant molecules with a liquid-crystalline order. The aqueous solution is located between the micelles. Spheres = hydrophilic ends of the surfactant molecules, black zigzag lines = long alkyl groups... 

Sixou et al. (101) showed the circular dichroism of cholesteric CTA solutions in TFA depends on the CTA molecular weight. The intensity of the circular dichroic peak increases with molecular weight. Meeten and Navard (97) studied gel formation and liquid crystallinity in TFA-H2O solutions of CTA. When water was added to a liquid crystalline solution of CTA in TFA a gel phase formed presumably by the formation of crosslinks due to hydrogen bonding. They interpreted their results that liquid crystalline ordering involves both inter- and intramolecular forces. 

A general concept for describing all kinds of order in chain molecules, ranging from crystalline order to liquid crystalline order and then to order in oriented and isotropic amorphous polymers, is introduced in the third article written by Pieper and Kilian. After the presentation of the basic concept, experimental results obtained on different polymers including phases with rotatory segmental motion are discussed. 

Blumstein, A. and Hsu, E. C. Liquid crystalline order in polymers with mesogenic side groups in Blumstein, A. ed. Liquid Crystalline Order in Polymers . Academic Press, New York, NY 1978, p. 105... 

The combination of crown ethers with mesogenic groups is interesting because the resulting hybrid materials possess the properties of both constructive subunits, i.e., liquid crystalline order in the mesophase and the ability to complex specific cations selectively according to the crown ether cavity size. 

A more recent trend in polymer materials research is the hybridization of cellulosic polysaccharides with inorganic compounds natural and synthetic layered clays, silica, zeolites, metal oxides, and apatites are employable as nanoscale components. In addition, if mesoscopic assemblies such as liquid-crystalline ordering are used in the construction of new compositional systems, the variety of functionalized cellulosic materials will be further expanded. 

Before and after the works described above, contributions to the design and fabrication of similar multicomponent films or gels of cholesteric character, mainly based on HPC, EC, or their derivatives were also made [202, 219-224], Some of these [219,220,224] dealt with shear-deformed network systems preserving a unique banded structure, so that the disappearance and recovery of the optical anisotropy could be controlled thermo-reversibly. Special mention should be made of the successful preparation of two novel classes of solid materials maintaining cholesteric liquid-crystalline order. One consists of essentially pure cellulose only, and the other is a ceramic silica with an imprint of cellulosic chiral mesomorphy. 

This article deals with some topics of the statistical physics of liquid-crystalline phase in the solutions of stiff chain macromolecules. These topics include the problem of the phase diagram for the liquid-crystalline transition in die solutions of completely stiff macromolecules (rigid rods) conditions of formation of the liquid-crystalline phase in the solutions ofsemiflexible macromolecules possibility of the intramolecular liquid-crystalline ordering in semiflexible macromolecules structure of intramolecular liquid crystals and dependence of die properties of the liquid-crystalline phase on the microstructure of the polymer chain. 

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