Anomalously Large Bend Elastic Constant and Faster Electro-Optic Response in Soft Glassy Gels Formed by a Dipeptide


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In this article, results of static/dynamic Freedericksz transformation and rheological studies on anisotropic thermoreversible gels formed by gelation of a nematic liquid crystal (NLC) with a monodisperse dipeptide are presented. Freedericksz transformation studies reveal a surprising result: the gel state possesses a very large Frank bend elastic constant value, order of magnitude higher than the sol state, whereas, the splay elastic constant shows relatively a small increase. The studies also demonstrate that the anisotropic gel to anisotropic sol transition can be tracked by simply monitoring the Freedericksz transformation. Other attractive features of the gel state include the vanishing of the undesirable backflow effect, and nearly an order of magnitude decrease of switching speed. Further, rheological studies bring out the soft glassy characteristics of these gels.



Solid State Phenomena (Volumes 181-182)

Edited by:

Yuan Ming Huang




G. G. Nair and R. Bhargavi, "Anomalously Large Bend Elastic Constant and Faster Electro-Optic Response in Soft Glassy Gels Formed by a Dipeptide", Solid State Phenomena, Vols. 181-182, pp. 14-21, 2012

Online since:

November 2011




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