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Heterogeneous Nanocomposite Materials Based on Liquid Crystals and Porous Media

Published online by Cambridge University Press:  10 February 2011

G. P. Sinha
Affiliation:
Department of Physics and Materials Research Center, PO BOX 23343, University of Puerto Rico, San Juan, PR 00931–3343, USA
F. M. Aliev
Affiliation:
Department of Physics and Materials Research Center, PO BOX 23343, University of Puerto Rico, San Juan, PR 00931–3343, USA
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Abstract

An effective way of preparing a variety of liquid crystal based nanocomposite materials is to disperse LC in porous media with different porous matrix structure, pore size and shape. We present the results of investigations of quasiequilibrium and dynamical properties of nematic and smectic liquid crystals (LC) dispersed in porous matrices with randomly oriented, interconnected pores (porous glasses) and parallel cylindrical pores (Anopore membranes) by light scattering, photon correlation and dielectric spectroscopies. Confining LC to nanoscale level leads to quantitative changes in physical properties and appearance of new behavior which does not exist in either of the components. Relaxation of director fluctuations which is characterized by single relaxation time in the bulk LC are transformed to a process with a spectrum of relaxation times in pores, which includes extremely slow dynamics typical for glass formers. Existence of developed interface in these materials leads to new dielectric properties such as an appearance of a low frequency relaxation of the polarization and modification of dipole rotation.

Type
Research Article
Copyright
Copyright © Materials Research Society 1997

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References

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