Datta, Ranajay ; Yelash, Leonid ; Schmid, Friederike ; Kummer, Florian ; Oberlack, Martin ; Lukáčová-Medvid’ová, Mária ; Virnau, Peter (2021)
Shear-Thinning in Oligomer Melts - Molecular Origins and Applications.
In: Polymers, 13 (16)
doi: 10.3390/polym13162806
Artikel, Bibliographie
Dies ist die neueste Version dieses Eintrags.
Kurzbeschreibung (Abstract)
We investigate the molecular origin of shear-thinning in melts of flexible, semiflexible and rigid oligomers with coarse-grained simulations of a sheared melt. Entanglements, alignment, stretching and tumbling modes or suppression of the latter all contribute to understanding how macroscopic flow properties emerge from the molecular level. In particular, we identify the rise and decline of entanglements with increasing chain stiffness as the major cause for the non-monotonic behaviour of the viscosity in equilibrium and at low shear rates, even for rather small oligomeric systems. At higher shear rates, chains align and disentangle, contributing to shear-thinning. By performing simulations of single chains in shear flow, we identify which of these phenomena are of collective nature and arise through interchain interactions and which are already present in dilute systems. Building upon these microscopic simulations, we identify by means of the Irving–Kirkwood formula the corresponding macroscopic stress tensor for a non-Newtonian polymer fluid. Shear-thinning effects in oligomer melts are also demonstrated by macroscopic simulations of channel flows. The latter have been obtained by the discontinuous Galerkin method approximating macroscopic polymer flows. Our study confirms the influence of microscopic details in the molecular structure of short polymers such as chain flexibility on macroscopic polymer flows.
| Typ des Eintrags: | Artikel |
|---|---|
| Erschienen: | 2021 |
| Autor(en): | Datta, Ranajay ; Yelash, Leonid ; Schmid, Friederike ; Kummer, Florian ; Oberlack, Martin ; Lukáčová-Medvid’ová, Mária ; Virnau, Peter |
| Art des Eintrags: | Bibliographie |
| Titel: | Shear-Thinning in Oligomer Melts - Molecular Origins and Applications |
| Sprache: | Englisch |
| Publikationsjahr: | 2021 |
| Ort: | Basel |
| Verlag: | MDPI |
| Titel der Zeitschrift, Zeitung oder Schriftenreihe: | Polymers |
| Jahrgang/Volume einer Zeitschrift: | 13 |
| (Heft-)Nummer: | 16 |
| Kollation: | 20 Seiten |
| DOI: | 10.3390/polym13162806 |
| Zugehörige Links: | |
| Kurzbeschreibung (Abstract): | We investigate the molecular origin of shear-thinning in melts of flexible, semiflexible and rigid oligomers with coarse-grained simulations of a sheared melt. Entanglements, alignment, stretching and tumbling modes or suppression of the latter all contribute to understanding how macroscopic flow properties emerge from the molecular level. In particular, we identify the rise and decline of entanglements with increasing chain stiffness as the major cause for the non-monotonic behaviour of the viscosity in equilibrium and at low shear rates, even for rather small oligomeric systems. At higher shear rates, chains align and disentangle, contributing to shear-thinning. By performing simulations of single chains in shear flow, we identify which of these phenomena are of collective nature and arise through interchain interactions and which are already present in dilute systems. Building upon these microscopic simulations, we identify by means of the Irving–Kirkwood formula the corresponding macroscopic stress tensor for a non-Newtonian polymer fluid. Shear-thinning effects in oligomer melts are also demonstrated by macroscopic simulations of channel flows. The latter have been obtained by the discontinuous Galerkin method approximating macroscopic polymer flows. Our study confirms the influence of microscopic details in the molecular structure of short polymers such as chain flexibility on macroscopic polymer flows. |
| Freie Schlagworte: | BoSSS, shear flow, shear-thinning, semiflexible polymers, oligomers, heterogeneous multiscale methods, molecular dynamics, discontinuous Galerkin method, soft matter, non-Newtonian fluids |
| Zusätzliche Informationen: | This article belongs to the Special Issue Semiflexible Polymers II |
| Sachgruppe der Dewey Dezimalklassifikatin (DDC): | 500 Naturwissenschaften und Mathematik > 510 Mathematik 500 Naturwissenschaften und Mathematik > 530 Physik 600 Technik, Medizin, angewandte Wissenschaften > 620 Ingenieurwissenschaften und Maschinenbau |
| Fachbereich(e)/-gebiet(e): | 16 Fachbereich Maschinenbau 16 Fachbereich Maschinenbau > Fachgebiet für Strömungsdynamik (fdy) |
| Hinterlegungsdatum: | 15 Nov 2023 08:36 |
| Letzte Änderung: | 15 Nov 2023 08:39 |
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| Suche nach Titel in: | TUfind oder in Google |
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Shear-Thinning in Oligomer Melts - Molecular Origins and Applications. (deposited 14 Nov 2023 13:49)
- Shear-Thinning in Oligomer Melts - Molecular Origins and Applications. (deposited 15 Nov 2023 08:36) [Gegenwärtig angezeigt]
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