Gelation and Yielding Behavior of Polymer-Nanoparticle Hydrogels

Polymer-Nanoparticle hydrogels are a unique class of self-assembled, shear-thinning, yield-stress fluids which have demonstrated potential utility in many impactful applications. Here we present a thorough analysis of the gelation and yielding behavior of these materials with respect to the polymer and nanoparticle component stoichiometry. Through comprehensive rheological and diffusion studies, we reveal insights into the structural dynamics of the polymer nanoparticle network which identify that stoichiometry plays a key role in gelation and yielding, ultimately enabling the development of hydrogel formulations with unique shear-thinning and yield-stress behaviors. Access to these materials opens new doors for interest- ing applications in a variety of fields including tissue engineering, drug delivery, and controlled solution viscosity.

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Gold implantation inn‐type silicon: Entropy factor and diffusion studies

Journal of Applied Physics ◽

10.1063/1.346638 ◽

1990 ◽

Vol 68 (4) ◽

pp. 1601-1605 ◽

Cited By ~ 17

Author(s):

S. Coffa ◽

L. Calcagno ◽

G. Ferla ◽

S. U. Campisano

Keyword(s):

Type Silicon ◽

Diffusion Studies ◽

Entropy Factor ◽

And Diffusion

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Pollution plume transport and diffusion studies using fluorescence lidar

Applied Optics ◽

10.1364/ao.19.002524 ◽

1980 ◽

Vol 19 (15) ◽

pp. 2524 ◽

Cited By ~ 8

Author(s):

Burton G. Schuster ◽

Thomas G. Kyle

Keyword(s):

Diffusion Studies ◽

Transport And Diffusion ◽

Plume Transport ◽

And Diffusion

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ULTRACENTRIFUGE AND DIFFUSION STUDIES ON GLUTEN

Canadian Journal of Research ◽

10.1139/cjr42c-014 ◽

1942 ◽

Vol 20c (3) ◽

pp. 130-159 ◽

Cited By ~ 12

Author(s):

A. G. McCalla ◽

Nils Gralén

Keyword(s):

Sodium Salicylate ◽

Minimum Weight ◽

Average Molecular Weight ◽

Sedimentation Equilibrium ◽

Velocity Sedimentation ◽

Molecular Characteristics ◽

Weight Average Molecular Weight ◽

Diffusion Constants ◽

Diffusion Studies ◽

And Diffusion

The molecular characteristics of gluten in sodium salicylate solutions were studied by means of sedimentation velocity, sedimentation equilibrium, and diffusion measurements. The proportion of total gluten protein molecularly dispersed increased with increase in concentration of sodium salicylate up to 12%, but the dispersed portions had essentially the same sedimentation constant (2.5 ± 0.15) regardless of the concentration of the dispersing medium.The most soluble 25 per cent of the gluten was all molecularly dispersed, but was definitely inhomogeneous. The weight-average molecular weight of this fraction was 44,000, but there is reason to believe the minimum weight may be about 35,000. None of the other fractions was entirely molecularly dispersed, the proportion decreasing with decreasing solubility of the fractions. Aggregates of many sizes existed in all of these fractions, but only the most insoluble contained aggregates large enough to cause opacity. Sedimentation constants of the molecularly dispersed portions increased slightly with decreasing solubility, while diffusion constants decreased markedly. None of the fractions yielded normal curves (diffusion diagrams) but the more soluble the fraction, the more nearly normal the curve. The inhomogeneity responsible for the varying rates of diffusion was due partly to differences in proportion and properties of the molecularly dispersed gluten and partly to aggregates.All properties showed progressive changes both within and between the arbitrarily produced fractions. These results, therefore, support the hypothesis that gluten is a protein system showing progressive and regular changes in properties with change in solubility.

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Sorption and diffusion studies in cementitious grouts

Waste Management ◽

10.1016/0956-053x(92)90055-n ◽

1992 ◽

Vol 12 (2-3) ◽

pp. 289-297 ◽

Cited By ~ 11

Author(s):

H.M. Johnston ◽

D.J. Wilmot

Keyword(s):

Diffusion Studies ◽

And Diffusion

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Electrical conduction and diffusion studies in NH4H2PO4 and KH2PO4 single crystals

Journal of Solid State Chemistry ◽

10.1016/0022-4596(77)90194-3 ◽

1977 ◽

Vol 21 (3) ◽

pp. 171-183 ◽

Cited By ~ 46

Author(s):

M. Sharon ◽

Anjan K. Kalia

Keyword(s):

Single Crystals ◽

Electrical Conduction ◽

Diffusion Studies ◽

And Diffusion

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Kinetics and diffusion studies in CA2 formation

Cement and Concrete Research ◽

10.1016/0008-8846(89)90064-1 ◽

1989 ◽

Vol 19 (1) ◽

pp. 47-52 ◽

Cited By ~ 10

Author(s):

M.M. Ali ◽

S.J. Raina ◽

V.K. Singh

Keyword(s):

Diffusion Studies ◽

And Diffusion

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Improved Calculation of Wellblock Pressures for Numerical Simulation of Non-Newtonian Polymer Injection

SPE Journal ◽

10.2118/205339-pa ◽

2021 ◽

pp. 1-12

Author(s):

Irfan Tai ◽

Marie Ann Giddins ◽

Ann Muggeridge

Keyword(s):

Numerical Simulation ◽

Oil Recovery ◽

Polymer Solutions ◽

Shear Thinning ◽

Injection Well ◽

Solution Viscosity ◽

Grid Refinement ◽

Equivalent Radius ◽

Local Grid Refinement ◽

Local Grid

Summary The viability of any enhanced-oil-recovery project depends on the ability to inject the displacing fluid at an economic rate. This is typically evaluated using finite-volume numerical simulation. These simulators calculate injectivity using the Peaceman method (Peaceman 1978), which assumes that flow is Newtonian. Most polymer solutions exhibit some degree of non-Newtonian behavior resulting in a changing polymer viscosity with distance from the injection well. For shear-thinning polymer solutions, conventional simulations can overpredict injection-well bottomhole pressure (BHP) by several hundred psi, unless a computationally costly local grid refinement is used in the near-wellboreregion. We show theoretically and numerically that the Peaceman pressure-equivalent radius, based on Darcy flow, is not correct when fluids are shear thinning, and derive an analytical expression for calculating the correct radius. The expression does not depend on any particular functional relationship between polymer-solution viscosity and velocity. We test it using the relationship described by the Meter equation (Meter and Bird 1964) and the Cannella et al. (1988) correlation. Numerical tests indicate that the solution provides a significant improvement in the accuracy of BHP calculations for conventional numerical simulation, reducing or removing the need for expensive local grid refinement around the well when simulating the injection of fluids with shear-thinningnon-Newtonianrheology.

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