Liquid-crystalline polysiloxanes

Other crystalline inorganic polymers such as poly(dichlorophosphazene), poly(aryloxyphosphazenes), liquid crystalline polysiloxanes and poly(dichloro-silane) have also been studied by X-ray diffraction methods, enabling the conformations in the crystallites in the solid state to be established. 

Finkelmann, H. and Rehage, G. Investigations on liquid crystalline polysiloxanes, I, Synthesis and characterization of linear polymers. Makromol. Chem. Rapid Commun. 1, 31 (1980)... 

Scheme 12 Synthesis of crown-containing liquid crystalline polysiloxane poly (23)...

Jones, B.A., Bradshaw, J.S., Nishioka, M., and Lee, M.L., Synthesis of smectic liquid-crystalline polysiloxanes from biphenylcarboxylate esters and their use as stationary phases for high-resolution gas chromatography, J. Org. Chem., 49, 4947, 1984. 

K. Markides, M. Nishioka, et al., Smectic biphenylcarboxylates ester liquid crystalline polysiloxane stationary phase for capillary gas chromatography, Anal. Chem., 57 1296-1299(1985). 

Liquid Crystalline Polysiloxane Surfaces and Edges of a Smectic Layered Ferroelectric... 

Petn, A., Kummer, S., Anneser, H., Eeiner, E, and Btauchle, C. Photoinduced reorientation of cholesteric liquid crystalline polysiloxanes and applications in optical information storge and second harmonic generation. Ber. Bunsenges. Phys. Chem. 97, 1281 (1993). 

The same authors prepared a series of liquid-crystalline polysiloxanes copolymerizing the nonionic mesogenic monomer cholest-5-en-3-ol(3P)-10-undecenoate 47 and the ionic mesogenic monomer potassium 2-allyloxy-5-cholesteryloxycar-bonyl-benzenesulfonate 48. 

The mesogenic behavior of 43 emphasizes the role played by the oc-tasilsesquioxane core when comparing with the related side-chain liquid-crystalline polysiloxanes [95,96]. It is remarkable that the thermal stability of the chiral nematic phase is similar in both the polymer and the dendrimer, suggesting that the cubic core does not perturb significantly the associations between the mesogens necessary to support the chiral nematic phase. 

Deschenaux and co-workers also isolated liquid crystalline polysiloxanes containing ferrocene in their side chains.236 These polymers contained either 1,3- or l,l -disubstituted ferrocene and were synthesized from the reaction of preformed polysiloxanes and vinyl organo-iron monomers. 

Liquid crystalline polysiloxane elastomers have been prepared in a two step process by reacting polymethylsiloxane with phenyl cinnamate containing mesogens having terminal vinyl groups235. 

Berset, J. D., Holzer, R., and Hani, H., Solving coelution problems on a smectic-liquid crystalline polysiloxane capillary column for the determination of priority polycyclic aromatic hydrocarbons in environmental samples, J. Chromatogr. A, 823, 179-187, 1998. 

Chang-Chien, G., Terminally carboxyl oligo(ethylene oxide) monomethyl ether-substituted side chain liquid crystalline polysiloxane polymer as stationary phase in capillary gas chromatography for the separation of polynuclear aromatic hydrocarbons, J. Chromatogr. A, 808, 201-209, 1998. 

Figure 23. Left Global and TS experiments obtained for a side-chain liquid-crystalline polysiloxane (data adapted from [177, 178], where more details are given), where at least three distinct relaxation processes can be found. Right Activation energy as a function of the temperature of the maximum of TS peaks obtained for the same polymer at different polarization temperatures, using r = 2 °C. The activation energy was calculated from the activation enthalpy, as reported in [177].

Yao, N., and Jamieson, A. M., Transient shear flow behavior of dilute solutions of side-chaiii liquid-crystalline polysiloxanes in 4,4/-(n-pentyloxy)cyanobiphenyl, Macromolecides, 31, 5399-5406 (1998). 

H. Endo, S. Hachiya, T. Sekiya, K. Kawasaki, Rotational viscosity of ferroelectric liquid-crystalline polysiloxanes. Liq. Cryst. 12, 147-155 (1992)... 

Z-type deposition) [238], In the case of certain substituted monomeric phthalo-cyanines a Z-type deposition is reported [189b, 224,228] while polymeric liquid crystalline polysiloxanes are transferred both on the down- and up-stroke (Y-type deposition) [239], For the dipping process the pH of the subphase and the surface pressure at which the dipping occurs are important variables which must be optimized in order to achieve high quality films. 

Although experimental studies have been of the greatest interest by far, there has been some molecular modeling of side-chain liquid-crystalline polysiloxanes. ... 

Masser, K. A. Patil, H. P. Hedden, R. C. Runt, J., Dynamics of Main-Chain Liquid Crystalline Polysiloxanes Containingp-Phenyleneterephthalate Mesogens. J. Non-Cryst. Solids 2010, 356, 578-581. 

Kaneko, K. Oto, K. Kawai, T. Choi, H. Kikuchi, H. Nakamura, N., Electrorhe-ological Effect and Electro-Optical Properties of Side-on Liquid Crystalline Polysiloxane in a Nematic Solvent. ChemPhysChem 2013,14(12), 2704-2710. 

Ganicz, T. Pakula, T. Fortuniak, W. Bialecka-Florjanczyk, E., Linear and Hy-perbranched Liquid Crystalline Polysiloxanes. Polymer 2005, 46,11380-11388. 

Meng, F.-B. Cui, Y. Chen, H.-B. Zhang, B.-Y. Jia, C., Phase Behaviors of Comb-Like Liquid-Crystalline Polysiloxanes Containing Fluorinated Meso-genic Units. Polymer 2009,50,1187-1196. 

Lacey, D. Beattie, H. N. Mitchell, G. R. Pople, J. A., Orientation Effects in Monodomain Nematic Liquid Crystalline Polysiloxane Elastomers. J. Mater. Chem. 1998,8,53-60. 

Meng, F. Lian, J. Zhang, B. Sun, Y., Chiral Side-Chain Liquid-Crystalline Polysiloxanes Bearing Fluorinated Mesogens and Cholesteryl Groups. Eur. Polym. J. 2008, 44, 504-513. 

Meng, F.-B. Gao, Y.-M. Zhang, B.-Y Xu, X.-X., Synthesis and Characterization of H-Bonded Side-Chain Liquid-Crystalline Polysiloxanes. J. Macromol. Set, Pure Appl. Chem. 2008, 45,186-194. 

Finkelmann, H. Kock, H.-J. Gleim, W. Rehage, G., Investigations on Liquid Crystalline Polysiloxanes, 5. Orientation of L-C-Elastomers by Mechanical Forces. Makromol. Rapid Commun. 1984, 5, 287-293. 

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