PHASE-BEHAVIOR OF CONCENTRATED SUSPENSIONS OF NEARLY HARD COLLOIDAL SPHERES
PHASE-BEHAVIOR OF CONCENTRATED SUSPENSIONS OF NEARLY HARD COLLOIDAL SPHERES
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DOI：
10.1038/320340a0
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发表时间：
1986-03-27
期刊：
影响因子：
64.8
通讯作者：
VANMEGEN, W
中科院分区：
文献类型：
--
作者：
PUSEY, PN;VANMEGEN, W
液体中球形胶体颗粒的悬浮液表现出令人着迷的各种相行为，可以模仿简单的原子液体和固体。“胶体流体”1-4和“胶体晶体”5-7都得到了广泛的研究，“胶体流体”1-4中相邻粒子的位置之间存在显著的短程相关性，而“胶体晶体”5-7则具有长程空间秩序。我们在这里报告了通过陡峭的排斥势相互作用的胶体球悬浮液的相图的详细研究。随着颗粒浓度的增加，我们观察到从胶体流体到流体和晶体共存，再到完全结晶的过程。在最高浓度下，我们得到了非常粘稠的样品，几个月后还没有完全结晶，其中的颗粒看起来像一个无定形的“胶体玻璃”。用有效的硬球模型可以较好地再现经验相图。对胶体玻璃相的观察是有趣的，不仅因为它本身，还因为它可能与制造高强度陶瓷有关。
Suspensions of spherical colloidal particles in a liquid show a fascinating variety of phase behaviour which can mimic that of simple atomic liquids and solids. ‘Colloidal fluids’1–4, in which there are significant short-range correlations between the positions of neighbouring particles, and ‘colloidal crystals’5–7, which have long-range spatial order, have been investigated extensively. We report here a detailed study of the phase diagram of suspensions of colloidal spheres which interact through a steep repulsive potential. With increasing particle concentration we observed a progression from colloidal fluid, to fluid and crystal phases in coexistence, to fully crystallized samples. At the highest concentrations we obtained very viscous samples in which full crystallization had not occurred after several months and in which the particles appeared to be arranged as an amorphous ‘colloidal glass’. The empirical phase diagram can be reproduced reasonably well by an effective hard-sphere model. The observation of the colloidal glass phase is interesting both in itself and because of possible relevance to the manufacture of high-strength ceramics8.