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Anomalous stress relaxation in random macromolecular networks

Kurt Broderix·Henning Löwe·Peter Müller·Annette Zippelius
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Abstract

Within the framework of a simple Rouse-type model we present exact analytical results for dynamical critical behaviour on the sol side of the gelation transition. The stress-relaxation function is shown to exhibit a stretched-exponential long-time decay. The divergence of the static shear viscosity is governed by the critical exponent $k=ϕ-β$, where $ϕ$ is the (first) crossover exponent of random resistor networks, and $β$ is the critical exponent for the gel fraction. We also derive new results on the behaviour of normal stress coefficients.

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Kurt Broderix, Henning Löwe, Peter Müller, Annette Zippelius. 2001-07-27. Anomalous stress relaxation in random macromolecular networks. https://doi.org/10.1016/s0378-4371(01)00471-x

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