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Fluctuation Effects on Microphase Separation in Random Copolymers

A. M. Gutin·C. D. Sfatos·E. I. Shakhnovich
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Abstract

We study random copolymers consisted of two kinds of monomers with attraction between similar kinds. The mean field analysis of this system indicates a continuous phase transition into a phase with periodic microdomain structure. It is shown that the inverse of the renormalized propagator has a minimum at non-zero wave-numbers. Consequently, there is an anomalously large contribution of fluctuations that make the disordered phase locally stable at every finite temperature. However, below a certain temperature, the ordered phase is shown to be locally stable and a weak first order transition is possible, similar to the weak crystallization theory developed by Brazovskii.

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A. M. Gutin, C. D. Sfatos, E. I. Shakhnovich. 1994-06-15. Fluctuation Effects on Microphase Separation in Random Copolymers. https://doi.org/10.1088/0305-4470%2F27%2F24%2F008

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