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Effect of Network Elasticity on Nematic Liquid Crystal/Cross-Linked Polymer Phase Diagram

Published online by Cambridge University Press:  10 February 2011

D. Nwabunma
Affiliation:
Institute of Polymer Engineering, The University of Akron, OH 44325-0301
T. Kyu
Affiliation:
Institute of Polymer Engineering, The University of Akron, OH 44325-0301
R.T. Pogue
Affiliation:
Science Applications International Corporation (SAIC) Dayton, OH 45431
T.J. Bunning
Affiliation:
AFRL/MLPJ, Materials and Manufacturing Directorate, WPAFB, OH 45433-6533
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Abstract

The influence of elasticity on the phase behavior of a mixture of nematic liquid crystal (LC) and in-situ cross-linked polymer has been investigated. Unlike the phase diagram of the LC/pre-cured polymer, the experimental diagram of LC/cross-linked polymer phase supported by theoretical calculation showed no critical point. Instead, the binodal curve exhibits an upward asymptotic behavior as the LC volume fraction approaches unity due to domination arising from network elasticity, particularly at high LC volume fraction. An examination of the effect of cross-links segment length and network functionality on the phase diagram of LC/cross-linked polymer showed that the segment length between cross-links exerts a greater influence.

Type
Research Article
Copyright
Copyright © Materials Research Society 1999

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References

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