Rheology of particle/water/oil three-phase dispersions

Electrostatic vs. capillary bridge forces

Mihail T. Georgiev, Krassimir D. Danov, Peter A. Kralchevsky*, Theodor D. Gurkov, Denitsa P. Krusteva, Luben N. Arnaudov, Simeon D. Stoyanov, Eddie G. Pelan

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

2 Citations (Scopus)

Abstract

Hypothesis Particle/water/oil three-phase capillary suspensions possess the remarkable property to solidify upon the addition of minimal amount of the second (dispersed) liquid. The hardening of these suspensions is due to capillary bridges, which interconnect the particles (pendular state). Electrostatic repulsion across the oily phase, where Debye screening by electrolyte is missing, could also influence the hardness of these suspensions. Experiments We present data for oil-continuous suspensions with aqueous capillary bridges between hydrophilic SiO2 particles at particle volume fractions 35–45%. The hardness is characterized by the yield stress Y for two different oils: mineral (hexadecane) and vegetable (soybean oil). Findings and modelling The comparison of data for the “mirror” systems of water- and oil-continuous capillary suspensions shows that Y is lower for the oil-continuous ones. The theoretical model of yield stress is upgraded by including a contribution from electrostatic repulsion, which partially counterbalances the capillary-bridge attraction and renders the suspensions softer. The particle charge density determined from data fits is close to that obtained in experiments with monolayers from charged colloid particles at oil/water interfaces. The results could contribute for better understanding, quantitative prediction and control of the mechanical properties of solid/liquid/liquid capillary suspensions.
Original languageEnglish
Pages (from-to)515-526
JournalJournal of Colloid and Interface Science
Volume513
DOIs
Publication statusPublished - 1 Mar 2018

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Dispersions
Rheology
Electrostatics
Suspensions
Oils
Water
Yield stress
Liquids
Hardness
Soybean oil
Vegetable oils
Mineral oils
Charge density
Colloids
Particles (particulate matter)
Mineral Oil
Soybean Oil
Hardening
Monolayers
Volume fraction

Keywords

  • Capillary bridges
  • Capillary suspensions
  • Pendular state
  • Silica particles
  • Suspension rheology
  • Wet granular materials
  • Yield stress

Cite this

Georgiev, M. T., Danov, K. D., Kralchevsky, P. A., Gurkov, T. D., Krusteva, D. P., Arnaudov, L. N., ... Pelan, E. G. (2018). Rheology of particle/water/oil three-phase dispersions: Electrostatic vs. capillary bridge forces. Journal of Colloid and Interface Science, 513, 515-526. https://doi.org/10.1016/j.jcis.2017.11.057
Georgiev, Mihail T. ; Danov, Krassimir D. ; Kralchevsky, Peter A. ; Gurkov, Theodor D. ; Krusteva, Denitsa P. ; Arnaudov, Luben N. ; Stoyanov, Simeon D. ; Pelan, Eddie G. / Rheology of particle/water/oil three-phase dispersions : Electrostatic vs. capillary bridge forces. In: Journal of Colloid and Interface Science. 2018 ; Vol. 513. pp. 515-526.
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abstract = "Hypothesis Particle/water/oil three-phase capillary suspensions possess the remarkable property to solidify upon the addition of minimal amount of the second (dispersed) liquid. The hardening of these suspensions is due to capillary bridges, which interconnect the particles (pendular state). Electrostatic repulsion across the oily phase, where Debye screening by electrolyte is missing, could also influence the hardness of these suspensions. Experiments We present data for oil-continuous suspensions with aqueous capillary bridges between hydrophilic SiO2 particles at particle volume fractions 35–45{\%}. The hardness is characterized by the yield stress Y for two different oils: mineral (hexadecane) and vegetable (soybean oil). Findings and modelling The comparison of data for the “mirror” systems of water- and oil-continuous capillary suspensions shows that Y is lower for the oil-continuous ones. The theoretical model of yield stress is upgraded by including a contribution from electrostatic repulsion, which partially counterbalances the capillary-bridge attraction and renders the suspensions softer. The particle charge density determined from data fits is close to that obtained in experiments with monolayers from charged colloid particles at oil/water interfaces. The results could contribute for better understanding, quantitative prediction and control of the mechanical properties of solid/liquid/liquid capillary suspensions.",
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Rheology of particle/water/oil three-phase dispersions : Electrostatic vs. capillary bridge forces. / Georgiev, Mihail T.; Danov, Krassimir D.; Kralchevsky, Peter A.; Gurkov, Theodor D.; Krusteva, Denitsa P.; Arnaudov, Luben N.; Stoyanov, Simeon D.; Pelan, Eddie G.

In: Journal of Colloid and Interface Science, Vol. 513, 01.03.2018, p. 515-526.

Research output: Contribution to journalArticleAcademicpeer-review

TY - JOUR

T1 - Rheology of particle/water/oil three-phase dispersions

T2 - Electrostatic vs. capillary bridge forces

AU - Georgiev, Mihail T.

AU - Danov, Krassimir D.

AU - Kralchevsky, Peter A.

AU - Gurkov, Theodor D.

AU - Krusteva, Denitsa P.

AU - Arnaudov, Luben N.

AU - Stoyanov, Simeon D.

AU - Pelan, Eddie G.

PY - 2018/3/1

Y1 - 2018/3/1

N2 - Hypothesis Particle/water/oil three-phase capillary suspensions possess the remarkable property to solidify upon the addition of minimal amount of the second (dispersed) liquid. The hardening of these suspensions is due to capillary bridges, which interconnect the particles (pendular state). Electrostatic repulsion across the oily phase, where Debye screening by electrolyte is missing, could also influence the hardness of these suspensions. Experiments We present data for oil-continuous suspensions with aqueous capillary bridges between hydrophilic SiO2 particles at particle volume fractions 35–45%. The hardness is characterized by the yield stress Y for two different oils: mineral (hexadecane) and vegetable (soybean oil). Findings and modelling The comparison of data for the “mirror” systems of water- and oil-continuous capillary suspensions shows that Y is lower for the oil-continuous ones. The theoretical model of yield stress is upgraded by including a contribution from electrostatic repulsion, which partially counterbalances the capillary-bridge attraction and renders the suspensions softer. The particle charge density determined from data fits is close to that obtained in experiments with monolayers from charged colloid particles at oil/water interfaces. The results could contribute for better understanding, quantitative prediction and control of the mechanical properties of solid/liquid/liquid capillary suspensions.

AB - Hypothesis Particle/water/oil three-phase capillary suspensions possess the remarkable property to solidify upon the addition of minimal amount of the second (dispersed) liquid. The hardening of these suspensions is due to capillary bridges, which interconnect the particles (pendular state). Electrostatic repulsion across the oily phase, where Debye screening by electrolyte is missing, could also influence the hardness of these suspensions. Experiments We present data for oil-continuous suspensions with aqueous capillary bridges between hydrophilic SiO2 particles at particle volume fractions 35–45%. The hardness is characterized by the yield stress Y for two different oils: mineral (hexadecane) and vegetable (soybean oil). Findings and modelling The comparison of data for the “mirror” systems of water- and oil-continuous capillary suspensions shows that Y is lower for the oil-continuous ones. The theoretical model of yield stress is upgraded by including a contribution from electrostatic repulsion, which partially counterbalances the capillary-bridge attraction and renders the suspensions softer. The particle charge density determined from data fits is close to that obtained in experiments with monolayers from charged colloid particles at oil/water interfaces. The results could contribute for better understanding, quantitative prediction and control of the mechanical properties of solid/liquid/liquid capillary suspensions.

KW - Capillary bridges

KW - Capillary suspensions

KW - Pendular state

KW - Silica particles

KW - Suspension rheology

KW - Wet granular materials

KW - Yield stress

U2 - 10.1016/j.jcis.2017.11.057

DO - 10.1016/j.jcis.2017.11.057

M3 - Article

VL - 513

SP - 515

EP - 526

JO - Journal of Colloid and Interface Science

JF - Journal of Colloid and Interface Science

SN - 0021-9797

ER -