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Dynamics of gelling liquids: a short survey

Henning Löwe·Peter Müller·Annette Zippelius
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Abstract

The dynamics of randomly crosslinked liquids is addressed via a Rouse- and a Zimm-type model with crosslink statistics taken either from bond percolation or Erdoes-Renyi random graphs. While the Rouse-type model isolates the effects of the random connectivity on the dynamics of molecular clusters, the Zimm-type model also accounts for hydrodynamic interactions on a preaveraged level. The incoherent intermediate scattering function is computed in thermal equilibrium, its critical behaviour near the sol-gel transition is analysed and related to the scaling of cluster diffusion constants at the critical point. Second, non-equilibrium dynamics is studied by looking at stress relaxation in a simple shear flow. Anomalous stress relaxation and critical rheological properties are derived. Some of the results contradict long-standing scaling arguments, which are shown to be flawed by inconsistencies.

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Henning Löwe, Peter Müller, Annette Zippelius. 2004-12-21. Dynamics of gelling liquids: a short survey. https://doi.org/10.1088/0953-8984%2F17%2F20%2F002

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