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arXiv · 2406.14741

Jamming Crossovers in a Confined Driven Polymer in Solution

Setarehalsadat Changizrezaei·Mikko Karttunen·Colin Denniston
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Abstract

We use lattice-Boltzmann molecular dynamics (LBMD) simulations to study the compression of a confined polymer immersed in a fluid and pushed by a large spherical colloid with a diameter comparable to the channel width. We examined the chain's deformation with both purely repulsive and weakly attractive Lennard-Jones (LJ) potentials applied between the monomers. The sphere's velocity was varied over 3 orders of magnitude. The chain is in a non-dense state at low pushing velocities for both repulsive and attractive monomer interactions. When the velocity of the spherical colloid exceeds a threshold $v^*$, the back end of the chain transitions to a high density state with low mean square monomer displacement (MSD) values. The front end, however, remains in a non-dense state with high MSD indicating a pseudo two-state coexistence. This crossover is also revealed through volume per monomer and MSD as a function of the sphere's velocity. We also studied polymer dynamics by investigating folding events at different times.

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Setarehalsadat Changizrezaei, Mikko Karttunen, Colin Denniston. 2024-06-20. Jamming Crossovers in a Confined Driven Polymer in Solution. https://doi.org/10.1039/d4sm00761a

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