title: Shear-enhanced adsorption of a homopolymeric globule mediated by surface catch bonds.
abstract: The adsorption of a single collapsed homopolymer onto a planar smooth surface in shear flow is investigated by means of Brownian hydrodynamics simulation. While cohesive intra-polymer forces are modeled by Lennard-Jones potentials, surface-monomer interactions are described by stochastic bonds whose two-state kinetics is characterized by three parameters: bond formation rate, bond dissociation rate and an effective catch bond parameter that describes how the force acting on a surface-monomer bond influences the dissociation rate. We construct adsorption state diagrams as a function of shear rate and all three surface-monomer bond parameters. We find shear-induced adsorption in a small range of parameters for low dissociation and association rates and only when the surface-monomer bond is near the transition between slip and catch bond behavior. By mapping on a simple surface-monomer interaction model with conservative pair potentials we try to estimate the conservative potential parameters necessary to observe shear-induced surface adsorption phenomena.
authors.affiliation: Fachbereich Physik, Freie Universität Berlin, Arnimallee 14, 14195, Berlin, Germany. radtkem@zedat.fu-berlin.de.
authors.forename: Matthias
authors.initials: M
authors.lastname: Radtke
authors.affiliation: Fachbereich Physik, Freie Universität Berlin, Arnimallee 14, 14195, Berlin, Germany.
authors.forename: Roland R
authors.initials: RR
authors.lastname: Netz
mesh_terms: D065966:Absorption, Physicochemical; D057446:Hydrodynamics; D008962:Models, Theoretical; D011108:Polymers / Q000737:chemistry*; D033081:Shear Strength; D013816:Thermodynamics
chemical_list: D011108:Polymers