Role of isostaticity and load-bearing microstructure in the elasticity of yielded colloidal gels

Proceedings of the National Academy of Sciences of the United States of America - Tập 109 Số 40 - Trang 16029-16034 - 2012
Lilian C. Hsiao1, Richmond S. Newman2, Sharon C. Glotzer3,4, Michael J. Solomon2
1Department of Chemical Engineering University of Michigan 2300 Hayward Street Ann Arbor MI 48109 USA.
2aDepartments of Chemical Engineering, and
3Material Science and Engineering, University of Michigan, 2300 Hayward Street, Ann Arbor, MI 48109
4bMaterial Science and Engineering, University of Michigan, 2300 Hayward Street, Ann Arbor, MI 48109

Tóm tắt

We report a simple correlation between microstructure and strain-dependent elasticity in colloidal gels by visualizing the evolution of cluster structure in high strain-rate flows. We control the initial gel microstructure by inducing different levels of isotropic depletion attraction between particles suspended in refractive index matched solvents. Contrary to previous ideas from mode coupling and micromechanical treatments, our studies show that bond breakage occurs mainly due to the erosion of rigid clusters that persist far beyond the yield strain. This rigidity contributes to gel elasticity even when the sample is fully fluidized; the origin of the elasticity is the slow Brownian relaxation of rigid, hydrodynamically interacting clusters. We find a power-law scaling of the elastic modulus with the stress-bearing volume fraction that is valid over a range of volume fractions and gelation conditions. These results provide a conceptual framework to quantitatively connect the flow-induced microstructure of soft materials to their nonlinear rheology.

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Tài liệu tham khảo

10.1088/0953-8984/19/32/323101

10.1126/science.1168375

10.1038/nmat3248

10.1016/S0142-9612(03)00340-5

10.1038/38699

10.1063/1.1683077

10.1038/nature06931

10.1103/PhysRevLett.106.105704

10.1039/b926076e

10.1122/1.3237154

10.1039/c0sm00957a

10.1103/PhysRevE.85.041403

10.1063/1.469317

10.1103/PhysRevLett.94.138301

10.1039/c1sm05598d

10.1088/0953-8984/16/42/014

10.1103/PhysRevLett.105.268301

10.1103/PhysRevLett.99.028301

10.1126/science.1207032

10.1080/14786446408643668

10.1021/la048554t

10.1103/PhysRevLett.94.208301

10.1038/nature08641

10.1103/PhysRevLett.106.138301

10.1038/nmat3119

10.1038/nmat2615

10.1038/nphys2127

10.1038/23819

10.1088/0953-8984/22/3/033101

10.1103/PhysRevLett.101.215501

10.1016/j.jcis.2005.02.018

10.1039/c1sm05271c

10.1016/j.cpc.2011.06.005

10.1146/annurev-conmatphys-062910-140526

J Mewis, NJ Wagner Colloidal Suspension Rheology (Cambridge Univ Press, Cambridge, UK, 2012).

10.1006/jcis.1996.4611

10.1016/j.jcis.2007.10.064

10.1021/la034636q

10.1103/PhysRevLett.101.038301

10.1002/smll.201102265

10.1006/jcis.1996.0217

10.1103/PhysRevE.74.041403

10.1122/1.549770

10.1122/1.3495981

JR Taylor An Introduction to Error Analysis—The Study of Uncertainties in Physical Measurements (Univ Science Books, Sausalito, CA, 1997).

10.1063/1.1674820

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Proceedings of the National Academy of Sciences of the United States of America

Tập 109 Số 40

16029-16034

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