Iterated stretching, extensional rheology and formation of beads-on-a-string structures in polymer solutions

Monica Oliveira, Roger Yeh, G.H. McKinley

Research output: Contribution to journalArticle

78 Citations (Scopus)

Abstract

The transient extensional rheology and the dynamics of elastocapillary thinning in aqueous solutions of polyethylene oxide (PEO) are studied with
high-speed digital video microscopy. At long times, the evolution of the thread radius deviates from self-similar exponential decay and competition
between elastic, capillary and inertial forces leads to the formation of a periodic array of beads connected by axially uniform ligaments. This
configuration is unstable and successive instabilities propagate from the necks connecting the beads and ligaments. This iterated process results
in multiple generations of beads developing along the string in general agreement with predictions of Chang et al. [Phys. Fluids, 11 (1999)
1717] although the experiments yield a different recursion relation between the successive generations of beads. At long times, finite extensibility
truncates the iterated instability, and slow axial translation of the bead arrays along the interconnecting threads leads to progressive coalescence
before the ultimate rupture of the fluid column. Despite these dynamical complexities it is still possible to measure the steady growth in the transient
extensional viscosity by monitoring the slow capillary-driven thinning in the cylindrical ligaments between beads.
LanguageEnglish
Pages137-146
JournalJournal of Non-Newtonian Fluid Mechanics
Volume137
Issue number1-3
DOIs
Publication statusPublished - 30 Aug 2006

Fingerprint

Polymer Solution
Rheology
Thinning
Ligaments
Polymer solutions
rheology
beads
Thread
Stretching
strings
Strings
Fluid
ligaments
Digital Video
Recursion Relations
Rupture
polymers
Exponential Decay
Microscopy
Oxides

Keywords

  • extensional rheology
  • beads on a string
  • self-similarity
  • iterative process

Cite this

@article{d75854287adb48909a9130fc391c2daa,
title = "Iterated stretching, extensional rheology and formation of beads-on-a-string structures in polymer solutions",
abstract = "The transient extensional rheology and the dynamics of elastocapillary thinning in aqueous solutions of polyethylene oxide (PEO) are studied withhigh-speed digital video microscopy. At long times, the evolution of the thread radius deviates from self-similar exponential decay and competitionbetween elastic, capillary and inertial forces leads to the formation of a periodic array of beads connected by axially uniform ligaments. Thisconfiguration is unstable and successive instabilities propagate from the necks connecting the beads and ligaments. This iterated process resultsin multiple generations of beads developing along the string in general agreement with predictions of Chang et al. [Phys. Fluids, 11 (1999)1717] although the experiments yield a different recursion relation between the successive generations of beads. At long times, finite extensibilitytruncates the iterated instability, and slow axial translation of the bead arrays along the interconnecting threads leads to progressive coalescencebefore the ultimate rupture of the fluid column. Despite these dynamical complexities it is still possible to measure the steady growth in the transientextensional viscosity by monitoring the slow capillary-driven thinning in the cylindrical ligaments between beads.",
keywords = "extensional rheology, beads on a string, self-similarity, iterative process",
author = "Monica Oliveira and Roger Yeh and G.H. McKinley",
year = "2006",
month = "8",
day = "30",
doi = "10.1016/j.jnnfm.2006.01.014",
language = "English",
volume = "137",
pages = "137--146",
journal = "Journal of Non-Newtonian Fluid Mechanics",
issn = "0377-0257",
number = "1-3",

}

Iterated stretching, extensional rheology and formation of beads-on-a-string structures in polymer solutions. / Oliveira, Monica; Yeh, Roger; McKinley, G.H.

In: Journal of Non-Newtonian Fluid Mechanics, Vol. 137, No. 1-3, 30.08.2006, p. 137-146.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Iterated stretching, extensional rheology and formation of beads-on-a-string structures in polymer solutions

AU - Oliveira, Monica

AU - Yeh, Roger

AU - McKinley, G.H.

PY - 2006/8/30

Y1 - 2006/8/30

N2 - The transient extensional rheology and the dynamics of elastocapillary thinning in aqueous solutions of polyethylene oxide (PEO) are studied withhigh-speed digital video microscopy. At long times, the evolution of the thread radius deviates from self-similar exponential decay and competitionbetween elastic, capillary and inertial forces leads to the formation of a periodic array of beads connected by axially uniform ligaments. Thisconfiguration is unstable and successive instabilities propagate from the necks connecting the beads and ligaments. This iterated process resultsin multiple generations of beads developing along the string in general agreement with predictions of Chang et al. [Phys. Fluids, 11 (1999)1717] although the experiments yield a different recursion relation between the successive generations of beads. At long times, finite extensibilitytruncates the iterated instability, and slow axial translation of the bead arrays along the interconnecting threads leads to progressive coalescencebefore the ultimate rupture of the fluid column. Despite these dynamical complexities it is still possible to measure the steady growth in the transientextensional viscosity by monitoring the slow capillary-driven thinning in the cylindrical ligaments between beads.

AB - The transient extensional rheology and the dynamics of elastocapillary thinning in aqueous solutions of polyethylene oxide (PEO) are studied withhigh-speed digital video microscopy. At long times, the evolution of the thread radius deviates from self-similar exponential decay and competitionbetween elastic, capillary and inertial forces leads to the formation of a periodic array of beads connected by axially uniform ligaments. Thisconfiguration is unstable and successive instabilities propagate from the necks connecting the beads and ligaments. This iterated process resultsin multiple generations of beads developing along the string in general agreement with predictions of Chang et al. [Phys. Fluids, 11 (1999)1717] although the experiments yield a different recursion relation between the successive generations of beads. At long times, finite extensibilitytruncates the iterated instability, and slow axial translation of the bead arrays along the interconnecting threads leads to progressive coalescencebefore the ultimate rupture of the fluid column. Despite these dynamical complexities it is still possible to measure the steady growth in the transientextensional viscosity by monitoring the slow capillary-driven thinning in the cylindrical ligaments between beads.

KW - extensional rheology

KW - beads on a string

KW - self-similarity

KW - iterative process

U2 - 10.1016/j.jnnfm.2006.01.014

DO - 10.1016/j.jnnfm.2006.01.014

M3 - Article

VL - 137

SP - 137

EP - 146

JO - Journal of Non-Newtonian Fluid Mechanics

T2 - Journal of Non-Newtonian Fluid Mechanics

JF - Journal of Non-Newtonian Fluid Mechanics

SN - 0377-0257

IS - 1-3

ER -