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arXiv · 2408.13743

Desorption of an active Brownian polymer from a homogeneous attractive surface

Guo-qiang Feng·Wen-de Tian
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Abstract

The interfacial behavior of active Brownian polymer (ABPO) is studied by Langevin dynamics simulations. On the dependence of adsorption strength and activity characterized by Peclet number (Pe), the polymer displays two typical states on the surface: adsorption and desorption states. We find the diffusion behavior of ABPO parallel to the surface yields the "active Rouse model" and activity causes the adsorption-desorption transition at a certain adsorption strength. Particular attention is paid to how the desorption time changes with the activity. At intermediate activity, desorption time displays an exponential decay with the inverse of effective temperature. Further, we observed a non-monotonic dependence of desorption time on the rotation diffusion coefficient of the monomer and found it exists a scaling relation with chain length N. Our results highlight the activity can be used to regulate the polymer adsorption and desorption behavior.

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Guo-qiang Feng, Wen-de Tian. 2024-08-25. Desorption of an active Brownian polymer from a homogeneous attractive surface. https://arxiv.org/abs/2408.13743

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