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Phase Diagram for Reversibly-Assembled Rod-Like Aggregates: Nematic, Columnar and Crystalline Ordering

Published online by Cambridge University Press:  21 February 2011

Mark P. Taylor  and
Judith Herzfeld
Mark P. Taylor
Affiliation:
Departments of Chemistry and Physics, Brandeis University, Waltham, MA 02254-9110 Departments of Physics, Brandeis University, Waltham, MA 02254-9110
Judith Herzfeld
Affiliation:
Departments of Chemistry and Physics, Brandeis University, Waltham, MA 02254-9110
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Abstract

Aqueous solutions of amphiphilic molecules which reversibly assemble into well defined polydisperse rod-like aggregates display a characteristic sequence of lyotropic mesophases including translational as well as orientational ordering. We have developed a model for such systems which incorporates a phenomenological description of aggregate assembly with a scaled particle calculation of the configurational entropy in the fluid dimensions and a cell theory description of the configurational entropy in the translationally ordered dimensions. The model reproduces many of the features seen in the experimental phase diagrams, including regions of isotropic, nematic, columnar and crystalline stability. In addition to the calculated phase diagram, related aggregate size distributions are reported.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 177: Symposium V – Macromolecular Liquids , 1989 , 135
Copyright
Copyright © Materials Research Society 1990

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References

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