Bicontinuous emulsions stabilized solely by colloidal particles
Bicontinuous emulsions stabilized solely by colloidal particles
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DOI：
10.1038/nmat2055
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发表时间：
2007-12-01
期刊：
影响因子：
41.2
通讯作者：
Clegg, P. S.
中科院分区：
文献类型：
--
作者：
Herzig, E. M.;White, K. A.;Clegg, P. S.
最近的大规模计算机模拟表明，有可能通过使用被两种液体中性润湿的颗粒（1）通过亚稳分解稳定和阻止二元液体分层中的双连续界面来创建一类新的软固体，称为“bijels”。颗粒的界面层预计是半渗透的（2）;因此，如果实现，这些新材料将具有许多潜在的应用，例如，作为微反应介质。然而，在实验室中创建bijels面临严重的障碍（3）。一般来说，快速淬火速率是必要的，以绕过成核，使只有有限厚度的样品可以生产，这破坏了假定的双连续网络的三维性。此外，即使两种液体对颗粒的润湿性很小程度的不相等，也会导致特征不佳的“润滑”界面层，从而导致不可再现的材料特性（3）。在这里，我们报告了一个可重复的协议，用于创建三维样品的bijel，其中的接口基本上是由一个单一的层颗粒稳定。我们演示了如何调整这些bijels的平均界面分离，并表明，机械，他们确实表现为软固体。这些特性和它们的可调性对于微流体应用将具有重要价值。
Recent large-scale computer simulations suggest that it may be possible to create a new class of soft solids, called 'bijels', by stabilizing and arresting the bicontinuous interface in a binary liquid demixing via spinodal decomposition using particles that are neutrally wetted by both liquids(1). The interfacial layer of particles is expected to be semi-permeable(2); hence, if realized, these new materials would have many potential applications, for example, as micro-reaction media. However, the creation of bijels in the laboratory faces serious obstacles(3). In general, fast quench rates are necessary to bypass nucleation, so that only samples with limited thickness can be produced, which destroys the three-dimensionality of the putative bicontinuous network. Moreover, even a small degree of unequal wettability of the particles by the two liquids can lead to ill-characterized, 'lumpy' interfacial layers and therefore irreproducible material properties(3). Here, we report a reproducible protocol for creating three-dimensional samples of bijel in which the interfaces are stabilized by essentially a single layer of particles. We demonstrate how to tune the mean interfacial separation in these bijels, and show that mechanically, they indeed behave as soft solids. These characteristics and their tunability will be of great value for microfluidic applications.