Structure and dynamics of grafted polymer layers: A Monte Carlo simulation

Abstract

The bond fluctuation model of polymer chains on lattices is used to study layers of polymers anchored with one end at a hard wall, assuming good solvent conditions and repulsive interactions between the monomers and the wall. Chain lengths from N=10 to N=80 and grafting densities σ from 0.025 to 0.20 are considered, both for the ‘‘quenched’’ case, where the anchor points are kept fixed at randomly chosen surface sites, and the ‘‘annealed’’ case, where lateral diffusion of the anchored ends at the wall is considered. Profiles of monomer density and free end density, chain linear dimensions parallel and perpendicular to the wall, as well as corresponding mean square displacements of inner and end monomers are studied and discussed in the light of current theoretical predictions, and it is shown that most of these properties can be understood in terms of appropriate scaling concepts. Both the relaxation of the total chain configurations and the time dependence of monomer mean square displacements are studied. In the annealed case the lateral diffusion constant D is found to behave as D∼σ−qN−p, where q=2/3 and p crosses over from p≊1 at small σ to p≊2 at large σ. The results for the relaxation time τ are consistent with the recent scaling prediction τ∼σbNa with a=3 and b=2/3.

Stimuli-Responsive Brushes with Active Minority Components: Monte Carlo Study and Analytical Theory

“…In the simulation community, a variety of numerical methods have been developed and used to investigate polymer brush systems, ranging from molecular dynamics [23], dissipative particle dynamics [24], and Monte Carlo (MC) simulations [25][26][27][28][29] to numerical selfconsistent field (SCF) calculations [30][31][32][33][34][35]. The present study mainly relies on MC simulations, while for comparison we also present results obtained from 3-d SCF theory.…”

Spherical polymer brushes under good solvent conditions: Molecular dynamics results compared to density functional theory

“…Refs. [17][18][19][20][21][22][23][24][25][26][27][28][29]. For many applications (building blocks of nanocomposites [30][31][32] , surface modification of biomolecules 15,33 etc.)…”

Monte Carlo simulations of an amphiphilic polymer at a hydrophobic/hydrophilic interface

“…Here, inter-chain steric repulsion, together with the desire for the chains to remain in contact with the solvent, forces the polymer chains to stretch out from the surface to form a layer. The behaviour of such tethered chains has been studied in detail [1] by experiment [2][3][4] and also by theory [5][6][7][8] and simulation [9][10][11]. The modification of the surface (or interface) properties by the polymer leads to useful applications, including controlling adhesion [12] and stabilizing colloidal dispersions [13].…”