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Role of Shear in the Isotropic to Lamellar Transition

Published online by Cambridge University Press:  21 February 2011

S. T. Milner  and
M. E. Cates
S. T. Milner
Affiliation:
Corporate Research Science Laboratories, Exxon Research and Engineering Company, Annandale, NJ 08801
M. E. Cates
Affiliation:
Cavendish Laboratory, Madingley Road, Cambridge CB3 OHE, UK
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Abstract

In the isotropic to lamellar transition, nonlinear fluctuation terms lower the transition temperature τc and drive the transition first order. Here we show that steady shear, by suppressing the fluctuations, raises τc; in a certain temperature range the lamellar phase can be induced by applying shear. A study of the effective potential indicates that the transition remains first order, though becoming very weak at high shear rate. We argue heuristically that the lamellar ordering first occurs with wavevector normal to both the velocity and the velocity gradient. We estimate the characteristic shear rate for two current experimental systems.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 177: Symposium V – Macromolecular Liquids , 1989 , 147
Copyright
Copyright © Materials Research Society 1990

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References

REFERENCES

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