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On the Derivation of a Density Functional Theory for Microphase Separation of Diblock Copolymers

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Abstract

We consider here the problem of phase separation in copolymer melts. The Ohta–Kawasaki density functional theory gives rise to a nonlocal Cahn–Hilliard-like functional, promoting the use of ansatz-free mathematical tools for the investigation of minimizers. In this article we re-derive this functional as an offspring of the self-consistent mean field theory, connecting all parameters to the fundamental material parameters and clearly identifying all the approximations used. As a simple example of an ansatz-free investigation, we calculate the surface tension in the strong segregation limit, independent of any phase geometry.

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Choksi, R., Ren, X. On the Derivation of a Density Functional Theory for Microphase Separation of Diblock Copolymers. Journal of Statistical Physics 113, 151–176 (2003). https://doi.org/10.1023/A:1025722804873

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