Scaling and Interactions of Linear and Ring Polymer Brushes via DPD Simulations

Autor(en)

Martin Jehser, Gerhard Zifferer, Christos Likos

Abstrakt

Single and double layers of polymer coated surfaces are investigated by means of Dissipative Particle Dynamics (DPD), focusing on the difference between grafted ring and linear chains. Several different surface coverages σ, as well as chain lengths N and brush separations D, are analyzed for athermal, i.e., good solvent, conditions. The size in the form of the radius of gyration R

_g, the shape as asphericity δ*, and orientation β*, as well as density profiles as functions of distance from grafting plane r(z), are studied. The effect of an added bond repulsion potential to suppress bond crossing in DPD is analyzed. Scaling laws of R

_g and its components R

_g⊥ and R

_g∥ are investigated. We find R

_g ∝ N

^v, v = 0.588 for surface coverages below the overlap surface concentration σ

_*. For σ > σ* we find R

_g⊥ ∝ N

^v⊥, v⊥ ≅ 1 and R

_g∥ ∝ N

^v∥k, v

_par; = 1/2 of ring brushes with the standard DPD model and v

_∥ ≅ 2/5 with added bond repulsion. The σ dependence of the radius of gyration was found to be R

_g ∝ σ

^μ with m = 1/3 for surface coverages grater than σ

_*. The perpendicular component R

_g⊥ scales independent of the bond repulsion potential as R

_g⊥ ∝ σ

^μ⊥, μ⊥ = 1/3, whereas the scaling of the parallel component exhibits a topological repulsion dependence R

_g⊥ ∝ σ

^μ∥, μ∥ = -1/12 for standard DPD and μ∥ = -1/6 for bond repulsion.

Organisation(en)

Institut für Physikalische Chemie, Computergestützte Physik und Physik der Weichen Materie

Journal

Polymers

Band

11

Anzahl der Seiten

17

ISSN

2073-4360

DOI

https://doi.org/10.3390/polym11030541

Publikationsdatum

03-2019

Peer-reviewed

Ja

ÖFOS 2012

104017 Physikalische Chemie, 103023 Polymerphysik, 104018 Polymerchemie

Schlagwörter

ASJC Scopus Sachgebiete

Allgemeine Chemie, Polymers and Plastics

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/4c8dea68-ef39-43d4-8a26-be66353c9123