我們在水包油的乳膠中觀察到新式的膠體叢聚。在這乳膠中，油滴裡分散著高分子鏈，而其表面也有許多膠體微粒會貼近在上面，尤其這些高分子鏈會引發膠體微粒間的空乏力作用。當油滴裡的膠體微粒數N大於4的時候，我們觀察到相對於N有多於一種的堆積組態。我們可以將這些組態細分成三個種類：第一種是滿足最小二價矩(minimal second moment)的叢聚；第二種是滿足球面堆積的叢聚；第三種是非等邊多面叢聚。它們都是由不同的機制所形成。很顯然的，微粒子的初始堆疊狀態以及乳膠油滴裡的高分子鏈濃度，兩者都在最終堆疊結果上扮演著重要的腳色。

We observed new types of colloidal clusters produced from oil-in-water emulsions in which colloidal microspheres are attached to emulsion surface and polymer dispersed in oil phase. The polymer induces depletion interaction between microspheres. When the number of particles N inside the droplet is larger than 4, we observed more than one configurations for each N. We classified the configurations into three catogories: The first kind is a minimal second moment cluster; the second kind is a spherical packing cluster; the third kind is a non-equilateral polyhedron cluster. They are formed through different mechanisms. Both initial packing of microspheres and the concentration of polymer in emulsion droplets play roles in their final packing.

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