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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
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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

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References

REFERENCES

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