Jump to main content
Jump to site search

Effects of surface roughness on self-diffusion dynamics of single polymer


We employ molecular dynamics simulations to simulate the diffusion dynamics of a single polymer adsorbed on surfaces with different roughness, which are characterized by the separation distance between obstacles and the height of obstacles. Our simulations demonstrate that for the strong adsorption and when the confinement of obstacles is strong enough for all chains, the scaling exponent α of the diffusion coefficient on the chain length exhibits three cases with the increase of the height of obstacles: a Rouse plateau with α ≈ -1 (the lateral motion of the polymer chains is free), a reptationlike plateau with α ≈ -1.5 (the polymer chains can hardly stride the obstacles in the perpendicular direction) and a transition from the Rouse plateau to the reptationlike plateau with -1.5 < α < -1 (the obstacles hinder the lateral motion of polymer chains). However, with the increase of the separation distance between obstacles, the confinement from the obstacles exhibits a decrease (more lateral motions of polymer chains are allowed), which results in the higher plateau (no longer a separate reptationlike dynamics). Our results clarify the effects of surface roughness on the diffusion mechanism of strongly adsorbed polymer chains on solid surfaces in dilute solutions and the resulting transition mechanism from the Rouse scaling to the reptationlike scaling, which is significant for the understanding of the physical nature and the development of the corresponding applications.

Back to tab navigation

Publication details

The article was received on 21 Dec 2017, accepted on 10 Apr 2018 and first published on 12 Apr 2018

Article type: Paper
DOI: 10.1039/C7SM02505J
Citation: Soft Matter, 2018, Accepted Manuscript
  •   Request permissions

    Effects of surface roughness on self-diffusion dynamics of single polymer

    J. Li, M. Ding, R. Zhang and T. Shi, Soft Matter, 2018, Accepted Manuscript , DOI: 10.1039/C7SM02505J

Search articles by author