Hostname: page-component-78c5997874-mlc7c Total loading time: 0 Render date: 2024-11-18T18:56:40.123Z Has data issue: false hasContentIssue false
  • English
  • Français

Anomalous Dielectric and Non-Linear Optical Response in Main and Side Chain Polymer Nematics and Smectics

Published online by Cambridge University Press:  26 February 2011

Mark Warner
Mark Warner*
Affiliation:
Cavendish Laboratory, Madingley Rd Cambridge, England, CB3 OHE
Get access

Abstract

I propose that certain, stereo-regular, main and side chain polymer liquid crystals would have a giant, long-time dielectric susceptibility, χ, of unusual temperature dependence

ϰ ∼ const.. exp{+h/kBT}

with a large ultimate low temperature value χ - χo N where χo is a susceptibility characteristic of a simple dielectric fluid and N the degree of polymerisation. The response would be caused by polarising molecular defects in the nematic ordering; de Gennes hair pins for main chain and torsional defects in side chain polymers. h is the defect energy.

Experimentally χ(2) - χo(2) N is known in the non-linear optical response of PBLG, a limiting case of main chain polymers with no hair pins.

The timescale for the response of side chain mesogens is predicted to vary as τ ~ N2.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 134: Symposium J – Materials Science and Engineering of Rigid-Rod Polymers , 1988 , 61
Copyright
Copyright © Materials Research Society 1989

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Gennes, P-G de in Polymer Liquid Crystals, edited by Cifferri, A., Krigbaum, W.R. and Meyer, R.B. (Academic Press, New York, 1982).Google Scholar
2. Levine, B.F. and Bethea, C.G., J. Chem. Phys. 65, 1989 (1976).CrossRefGoogle Scholar
3. Doi, M. and Edwards, S.F. Theory of Polymer Dynamics (Oxford University Press, Oxford, 1986).Google Scholar
4 Gunn, J.M.F. and Warner, M., Phys. Rev. Letts. 58, 393 (1987).Google Scholar
5. Warner, M. and Liu, H., Liq. Cryst., to be published, 1989.Google Scholar
6. (a) Maret, G., Volino, F., Blumstein, RB, Martins, AF and Blumstein, A., Proc. 27 th Int. Symp. Macromolecules (Strasbourg, 1981). (b) JF D'Allest, P. Sixou, A Blumstein, RB Blumstein, J. Teixeira and L. Noirez, Mol. Cryst. Liq Cryst. 155 581 (1988).Google Scholar
7. Bosch, A. ten, Maissa, P. and Sixou, P., J. Phys. (Paris) Lett. 44, L105 (1983). (there are some differences between this work and [8] and [9]).CrossRefGoogle Scholar
8. Rusakov, V.V. and Schliomis, M.I., J. Phys. (Paris) Lett. 46, L935 (1985).Google Scholar
9. Wang, X-J. and Warner, M., J. Phys. A19, 2215 (1986).Google Scholar
10. Warner, M., Gunn, J.M.F. and Baumgdrtner, A., J. Phys. A18, 3007 (1985).Google Scholar
11. Wang, X-J. and Warner, M., J. Phys. A20, 713 (1987).Google Scholar
12. Keller, R., Carvalho, B., Cotton, J.P., Lambert, M., Moussa, M. and Pepy, G., J. Phys. (Paris) 46, L1065 (1985).Google Scholar
13. Williams, D.R.M. and Warner, M., to be published.Google Scholar