6533b85afe1ef96bd12b9f29

RESEARCH PRODUCT

Polymer absorption in dense polymer brushes vs. polymer adsorption on the brush-solvent interface

Kurt BinderAndrey MilchevAndrey Milchev

subject

chemistry.chemical_classificationQuantitative Biology::BiomoleculesMaterials scienceRelaxation (NMR)General Physics and AstronomyPolymerPolymer adsorptionCondensed Matter::Soft Condensed Matterchemistry.chemical_compoundReptationMonomerAdsorptionchemistryChemical physicsAbsorption (chemistry)Macromolecule

description

Molecular-dynamics simulations of a coarse-grained model of a dense brush of flexible polymers (of type A) interacting with a long flexible macromolecule (of type B) are presented, considering the case of an attractive AB interaction, while effective interactions between AA and BB pairs of monomers are repulsive. Varying the strength of the attraction between unlike monomers, an adsorption transition at some critical value is found, where the B-chain is bound to the brush-solvent interface, similar to the adsorption on a planar solid substrate. However, when is much higher than , the long macromolecule is gradually “sucked in” the brush, developing many pieces that are locally stretched in the z-direction perpendicular to the substrate, in order to fit between the brush chains. The resulting hairpin-like structures of the absorbed chain shows up via oscillatory decay of the bond vector autocorrelation function. Chain relaxation is only possible via reptation.

https://doi.org/10.1209/0295-5075/106/58001