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arXiv · 1610.08752

Effects of disorder and chain stiffening on the elasticity of flexible polymer networks

Christiane Caroli·Anaël Lemaître
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Abstract

We examine how the distribution of contour lengths and the high-stretch stiffening of individual chain segments affect the macroscopic shear modulus of flexible polymer gels, using a 2D numerical model, in which polymer segments form a triangular network and disorder is introduced by varying their contour lengths. We show that in the relevant parameter range: (i) the non-affine contribution to the shear modulus is negligible, i.e. the Born approximation is satisfactory; (ii) the shear modulus is dominated by the contribution originating from equilibrium chain tensions. Moreover, mechanical equilibration at the nodes induces specific correlations between the end-to-end distances and contour lengths of chain segments, which must be properly accounted for to construct reasonable estimates of chain pressure and shear modulus.

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Christiane Caroli, Anaël Lemaître. 2016-10-27. Effects of disorder and chain stiffening on the elasticity of flexible polymer networks. https://doi.org/10.1103/physreve.95.032501

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