Particle configurations and gelation in capillary suspensions
Particle configurations and gelation in capillary suspensions
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DOI：
10.1039/c2sm07347a
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发表时间：
2012-01-01
期刊：
影响因子：
3.4
通讯作者：
Willenbacher, Norbert
中科院分区：
文献类型：
--
作者：
Koos, Erin;Willenbacher, Norbert
当在悬浮液的连续相中加入少量（小于1%）的第二种不混相液体时，外加剂的流变性能发生显著变化，可以从类流体状态变为类凝胶状态。如果二级液体优先湿润颗粒（摆态），或者二级液体湿润颗粒不如一级流体（毛细管态），这些所谓的毛细管悬浮液会转变为凝胶状状态。在毛细管状态下，二次液的分布和网络形成机理尚未得到研究。在这里，我们讨论了粒子簇的形成——它们被认为是观察到的样本跨越网络的基本组成部分——作为接触角和二次流体体积的函数。这些团簇的存在和强度与实验观察到的毛细管状态悬浮液的流变特性直接相关。
When a small amount (less than 1%) of a second immiscible liquid is added to the continuous phase of a suspension, the rheological properties of the admixture are dramatically altered and can change from a fluid-like to a gel-like state. These so-called capillary suspensions transition to a gel-like state both if the secondary liquid preferentially wets the particles (pendular state) and even if the secondary liquid wets the particles less well than the primary fluid (capillary state). The mechanism of network formation and the distribution of the secondary liquid in the capillary state has not been investigated so far. Here, we discuss the formation of particle clusters-which are assumed to be the basic building blocks of the observed sample-spanning network-as a function of the contact angle and secondary fluid volume. The presence and strength of these clusters is directly related to the experimentally observed rheological features of capillary state suspensions.