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DOI	10.1073/pnas.2022339118
	Time-connectivity superposition and the gel/glass duality of weak colloidal gels
	Keshavarz B.; Rodrigues D.G.; Champenois J.-B.; Frith M.G.; Ilavsky J.; Geri M.; Divoux T.; McKinley G.H.; Poulesquen A.
发表日期	2021
ISSN	00278424
卷号	118 期号:15
英文摘要	Colloidal gels result from the aggregation of Brownian particles suspended in a solvent. Gelation is induced by attractive interactions between individual particles that drive the formation of clusters, which in turn aggregate to form a space-spanning structure. We study this process in aluminosilicate colloidal gels through time-resolved structural and mechanical spectroscopy. Using the time-connectivity superposition principle a series of rapidly acquired linear viscoelastic spectra, measured throughout the gelation process by applying an exponential chirp protocol, are rescaled onto a universal master curve that spans over eight orders of magnitude in reduced frequency. This analysis reveals that the underlying relaxation time spectrum of the colloidal gel is symmetric in time with power-law tails characterized by a single exponent that is set at the gel point. The microstructural mechanical network has a dual character; at short length scales and fast times it appears glassy, whereas at longer times and larger scales it is gel-like. These results can be captured by a simple three-parameter constitutive model and demonstrate that the microstructure of a mature colloidal gel bears the residual skeleton of the original sample-spanning network that is created at the gel point. Our conclusions are confirmed by applying the same technique to another well-known colloidal gel system composed of attractive silica nanoparticles. The results illustrate the power of the time-connectivity superposition principle for this class of soft glassy materials and provide a compact description for the dichotomous viscoelastic nature of weak colloidal gels. © 2021 National Academy of Sciences. All rights reserved.
英文关键词	Aluminosilicate; Gels and glasses; Relaxation time spectrum; Time-connectivity superposition; Weak colloidal gels
语种	英语
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/179910
作者单位	Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States; Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Direction des Énergies, Institut des Sciences et Technologies pour une Economie Circulaire des Énergies bas Carbone, Département de Recherche sur les Technologies pour l'Enrichissement, Le Démantèlement et les Déchets, Service d'Études des Technologies pour l'Assainissement-Démantèlement et l'Étanchéité, Laboratoire d'Études des Ciments et Bitumes pour le Conditionnement, Université Montpellier, Bagnols-sur-Cèze, 30207, France; Advanced Photon Source, Argonne National Laboratory, Lemont, IL 60439, United States; MultiScale Materials Science for Energy and Environment, Unité Mixte Internationale 3466, CNRS-Massachusetts Institute of Technology, Cambridge, MA 02139, United States; Université de Lyon, École Normale Supérieure de Lyon, Université Claude Bernard, Laboratoire de Physique, CNRS, Lyon, F-69342, France
推荐引用方式 GB/T 7714	Keshavarz B.,Rodrigues D.G.,Champenois J.-B.,et al. Time-connectivity superposition and the gel/glass duality of weak colloidal gels[J],2021,118(15).
APA	Keshavarz B..,Rodrigues D.G..,Champenois J.-B..,Frith M.G..,Ilavsky J..,...&Poulesquen A..(2021).Time-connectivity superposition and the gel/glass duality of weak colloidal gels.Proceedings of the National Academy of Sciences of the United States of America,118(15).
MLA	Keshavarz B.,et al."Time-connectivity superposition and the gel/glass duality of weak colloidal gels".Proceedings of the National Academy of Sciences of the United States of America 118.15(2021).