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Viscoelasticity near the gel-point: a molecular dynamics study

D. C. Vernon·Michael Plischke·Bela Joos
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Abstract

We report on extensive molecular dynamics simulations on systems of soft spheres of functionality f, i.e. particles that are capable of bonding irreversibly with a maximum of f other particles. These bonds are randomly distributed throughout the system and imposed with probability p. At a critical concentration of bonds, p_c approximately equal to 0.2488 for f=6, a gel is formed and the shear viscosity ηdiverges according to η~ (p_c-p)^{-s}. We find s is approximately 0.7 in agreement with some experiments and with a recent theoretical prediction based on Rouse dynamics of phantom chains. The diffusion constant decreases as the gel point is approached but does not display a well-defined power law.

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D. C. Vernon, Michael Plischke, Bela Joos. 2001-02-15. Viscoelasticity near the gel-point: a molecular dynamics study. https://doi.org/10.1103/physreve.64.031505

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