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arXiv · 1402.1118

Universality of Block Copolymer Melts

Jens Glaser·Pavani Medapuram·Thomas M. Beardsley·Mark W. Matsen·David C. Morse
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Abstract

Simulations of five different coarse-grained models of symmetric diblock copolymer melts are compared to demonstrate a universal (i.e., model-independent) dependence of the free energy on the invariant degree of polymerization $\overline{N}$, and to study universal properties of the order-disorder transition (ODT). The ODT appears to exhibit two regimes: Systems of very long chains ($\overline{N} \gtrsim 10^{4}$) are well described by the Fredrickson-Helfand theory, which assumes weak segregation near the ODT. Systems of smaller but experimentally relevant values, $\overline{N} \lesssim 10^4$, undergo a transition between strongly segregated disordered and lamellar phases that, though universal, is not adequately described by any existing theory.

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Jens Glaser, Pavani Medapuram, Thomas M. Beardsley, Mark W. Matsen, David C. Morse. 2014-02-05. Universality of Block Copolymer Melts. https://doi.org/10.1103/physrevlett.113.068302

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