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arXiv · 1611.02311

Jamming of semiflexible polymers

Robert S. Hoy
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Abstract

We study jamming in model freely rotating polymers as a function of chain length $N$ and bond angle $θ_0$. The volume fraction at jamming, $ϕ_J(θ_0)$, is minimal for rigid-rod-like chains ($θ_0 = 0$), and increases monotonically with increasing $θ_0 \leq π/2$. In contrast to flexible polymers, marginally jammed states of freely rotating polymers are highly hypostatic, even when bond and angle constraints are accounted for. Large aspect ratio (small $θ_0$) chains behave comparably to stiff fibers: resistance to large-scale bending plays a major role in their jamming phenomenology. Low aspect ratio (large $θ_0$) chains behave more like flexible polymers, but still jam at much lower densities due to the presence of frozen-in 3-body correlations corresponding to the fixed bond angles. Long-chain systems jam at lower $ϕ$ and are more hypostatic at jamming than short-chain systems. Implications of these findings for polymer solidification are discussed.

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Robert S. Hoy. 2016-11-07. Jamming of semiflexible polymers. https://doi.org/10.1103/physrevlett.118.068002

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