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Role of cross-links in bundle formation, phase separation and gelation of long filaments

A. Zilman·S. Safran
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Abstract

We predict the thermodynamic and structural behavior of solutions of long cross-linked filaments. We find that at the mean field level, the entropy of self-assembled junctions induces an effective attraction between the filaments that can result in a phase separation into a connected network, in equilibrium with a dilute phase. A connected network can also be formed in a non-thermodynamic transition upon increase of the chain, or cross link density, or with decreasing temperature. For rigid rods, at low temperatures, we predict a transition from an isotropic network, to anisotropic bundles of rods tightly bound by cross links, that is triggered by the interplay between the configurational entropy of the cross-link distribution among the rods, and the rotational and translational entropy of the rods.

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A. Zilman, S. Safran. 2004-06-01. Role of cross-links in bundle formation, phase separation and gelation of long filaments. https://doi.org/10.1209/epl%2Fi2003-00489-5

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