Hquid crystal polymers

More recently, Raman spectroscopy has been used to investigate the vibrational spectroscopy of polymer Hquid crystals (46) (see Liquid crystalline materials), the kinetics of polymerization (47) (see Kinetic measurements), synthetic polymers and mbbers (48), and stress and strain in fibers and composites (49) (see Composite materials). The relationship between Raman spectra and the stmcture of conjugated and conducting polymers has been reviewed (50,51). In addition, a general review of ft-Raman studies of polymers has been pubUshed (52). 

Fig. 14. Main-chain polymer Hquid crystal phases (a) nematic, (b) smectic.

Fig. 15. Molecular stmcture and phases of a typical polysdoxane side-chain polymer Hquid crystal.

If a modest number of cross-links between the polymer backbone are introduced, the polymer Hquid crystal takes on elastomeric properties. The useflilness of these materials probably Hes in the coupling of mechanical and optical effects. 

Onogi, S. Asada, T. Rheology and rheo-optics of polymer hquid crystals. In Rheology Volume 1 Principles Astarita, G., Marrucci, G., Nicolais, L., Eds. Plenum Press New York, 1980 127-147. 

DeGennes PG (1982) Mechanical properties of nematic polymers. In Ciferri A, Krigbaum WR, Meyer RB (eds) Polymer hquid crystals. Academic Press, New York Hardouin F, Sigaud G, Achard MF, Brulet A, Cotton JP, Yoon DY, Percec V, Kawasumi M (1995) Macromolecules 28 5427... 

Furuya, H., Abe, A., Fuhrmann, K., Ballauff, M., and Fischer, E. W., SQUID studies of main-chain polymer hquid crystals and a rotational isomeric state treatment of the data. Macromolecules, 24, 2999-3003 (1991). 

Discuss effects of pre-drawing on mechanical properties of polymer hquid crystals. 

Discuss the behavior of polymer hquid crystals in magnetic fields. 

DEM Demyanchuk, I., Wieczorek, S.A., and Holyst, A., Phase separation in binaiy polymer/hquid crystal mixtures network breaking and domain growth by coalescence-induced coalescence, J. Phys. Chem. B, 110, 9869,2006. 

RIC Riccardi, C.C., Borrajo, J., Williams, R.J.J., Siddiqi, H.M., Dmnon, M., and Pascault, J.P., Multiple phase equihbria in poly disperse polymer/hquid crystal blends. Macromolecules, 31, 1124, 1998. 

M. Bar6n, Definitions of basic terms relating to low-molar-m iss md polymer hquid crystals. PureApll. Chem. 73,845-895 (2001). 

T. Yamamoto et al., Holographic gratings and holographic image storage via photochemical phase transitions of azobenzene polymer hquid crystal films, ... 

FIGURE 2.3 Schematic representation of (a) nematic phase and (b) smectic phase for main-chain liquid crystalline polymers, showing the director as the arrow. The relative ordering is the same for side-chain-polymer hquid crystals. 

Burghardt WR, EuUer GG. Role of director tumbling in the rheology of polymer hquid-crystal solutions. Macromolecules 1991 24 2546-55. 

Jerome B, Commandeur J, de Jeu WH. Backbone effects on the anchoring of side-chain polymer hquid crystals. Liq Cryst 1997 22 685-92. 

Tondiglia, V. P., L. V. Natarajan, R. L. Sutherland, D. Tomlin, and T. J. Buiming. 2002. Holographic formation of electro-optical polymer-hquid crystal photonic crystals. Adv. Mater. 14 187-191. 

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