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Packing structure of semiflexible rings.

ABSTRACT: Unraveling the packing structure of dense assemblies of semiflexible rings is not only fundamental for the dynamical description of polymer rings, but also key to understand biopackaging, such as observed in circular DNA of viruses or genome folding. Here we use X-ray tomography to study the geometrical and topological features of disordered packings of rubber bands in a cylindrical container. Assemblies of short bands assume a liquid-like disordered structure, with short-range orientational order, and reveal only minor influence of the container. In the case of longer bands, the confinement causes folded configurations and the bands interpenetrate and entangle. Most of the systems are found to display a threading network which percolates the system. Surprisingly, for long bands whose diameter is more than twice the diameter of the container, we found that all bands interpenetrate each other, in a complex fully entangled structure.

SUBMITTER: Gomez LR

PROVIDER: S-EPMC7035624 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Packing structure of semiflexible rings.

Gómez Leopoldo R LR García Nicolás A NA Pöschel Thorsten T

Proceedings of the National Academy of Sciences of the United States of America 20200205 7

Unraveling the packing structure of dense assemblies of semiflexible rings is not only fundamental for the dynamical description of polymer rings, but also key to understand biopackaging, such as observed in circular DNA of viruses or genome folding. Here we use X-ray tomography to study the geometrical and topological features of disordered packings of rubber bands in a cylindrical container. Assemblies of short bands assume a liquid-like disordered structure, with short-range orientational ord ...[more]

PMID: 32024763

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