Colloidal gel elasticity arises from the packing of locally glassy clusters
Colloidal gel elasticity arises from the packing of locally glassy clusters
复制标题
胶体凝胶弹性源自局部玻璃状簇的堆积
作者：
Kathryn A. Whitaker;Z. Varga;L. Hsiao;M. Solomon;J. Swan;E. Furst
滞留相分离形成的胶体凝胶广泛存在于农业、生物技术和先进制造业中，然而，在这些丰富的材料中，弹性的出现和滞留状态的性质仍然没有解决。在这里，综合实验、计算和图论方法之间的定量一致性被用来理解凝胶弹性响应的停滞状态和来源。微观结构的弹性来源是通过L平衡图将凝胶划分为最小互连的团簇，作为刚性的承载单元。集群-集群连接的数量密度随着吸引力的增加而增长，并用经典的柯西出生理论解释了网络中弹性的出现。团簇是无定形的，是等静定的。在低吸引强度时，内部团簇浓度映射到已知的吸引人的粘性胶体玻璃线上，并将其扩展到高强度和低颗粒体积分数。胶体凝胶通常由分散在液体中的固体颗粒组成，显示出一些特殊的机械性能，但其起源在很大程度上仍未解决。在这里，惠特克等人。结果表明，阻止相分离形成的弹性来自于凝胶中玻璃团簇的堆积。
Colloidal gels formed by arrested phase separation are found widely in agriculture, biotechnology, and advanced manufacturing; yet, the emergence of elasticity and the nature of the arrested state in these abundant materials remains unresolved. Here, the quantitative agreement between integrated experimental, computational, and graph theoretic approaches are used to understand the arrested state and the origins of the gel elastic response. The micro-structural source of elasticity is identified by the l-balanced graph partition of the gels into minimally interconnected clusters that act as rigid, load bearing units. The number density of cluster-cluster connections grows with increasing attraction, and explains the emergence of elasticity in the network through the classic Cauchy-Born theory. Clusters are amorphous and iso-static. The internal cluster concentration maps onto the known attractive glass line of sticky colloids at low attraction strengths and extends it to higher strengths and lower particle volume fractions. Colloidal gels are typically composed of solid particles dispersed in a liquid, which show some peculiar mechanic properties but their origins remain largely unsolved. Here, Whitaker et al. show that the elasticity formed via arrested phase separation arises from the packing of glassy clusters in gels.
DOI：
10.1126/science.aai8830
发表时间：
2017-11-24
期刊：
Science (New York, N.Y.)
影响因子：
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作者：
Cubuk ED;Ivancic RJS;Schoenholz SS;Strickland DJ;Basu A;Davidson ZS;Fontaine J;Hor JL;Huang YR;Jiang Y;Keim NC;Koshigan KD;Lefever JA;Liu T;Ma XG;Magagnosc DJ;Morrow E;Ortiz CP;Rieser JM;Shavit A;Still T;Xu Y;Zhang Y;Nordstrom KN;Arratia PE;Carpick RW;Durian DJ;Fakhraai Z;Jerolmack DJ;Lee D;Li J;Riggleman R;Turner KT;Yodh AG;Gianola DS;Liu AJ
通讯作者：
Liu AJ