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A practical density functional for polydisperse polymers

I. Pagonabarraga·M. E. Cates
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Abstract

The Flory Huggins equation of state for monodisperse polymers can be turned into a density functional by adding a square gradient term, with a coefficient fixed by appeal to RPA (random phase approximation). We present instead a model nonlocal functional in which each polymer is replaced by a deterministic, penetrable particle of known shape. This reproduces the RPA and square gradient theories in the small deviation and/or weak gradient limits, and can readily be extended to polydisperse chains. The utility of the new functional is shown for the case of a polydisperse polymer solution at coexistence in a poor solvent.

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I. Pagonabarraga, M. E. Cates. 2001-04-24. A practical density functional for polydisperse polymers. https://doi.org/10.1209/epl%2Fi2001-00422-6

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