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Shear viscosity of a crosslinked polymer melt

Kurt Broderix·Henning Loewe·Peter Mueller·Annette Zippelius
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Abstract

We investigate the static shear viscosity on the sol side of the vulcanization transition within a minimal mesoscopic model for the Rouse-dynamics of a randomly crosslinked melt of phantom polymers. We derive an exact relation between the viscosity and the resistances measured in a corresponding random resistor network. This enables us to calculate the viscosity exactly for an ensemble of crosslinks without correlations. The viscosity diverges logarithmically as the critical point is approached. For a more realistic ensemble of crosslinks amenable to the scaling description of percolation, we prove the scaling relation $k=ϕ-β$ between the critical exponent $k$ of the viscosity, the thermal exponent $β$ associated with the gel fraction and the crossover exponent $ϕ$ of a random resistor network.

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Kurt Broderix, Henning Loewe, Peter Mueller, Annette Zippelius. 1999-07-05. Shear viscosity of a crosslinked polymer melt. https://doi.org/10.1209/epl%2Fi1999-00500-3

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