建立了一种组装亚微米级聚苯乙烯微球的方法,称作蒸发自组装法.该方法是在一定温度下,聚苯乙烯微球随着分散介质的蒸发在悬浮液的气-液相界面处进行高效组装的过程.扫描电子显微镜显示组装体为规则排列的密堆积面心立方结构.研究发现,气-液界面处生成的组装体强烈地阻碍着分散介质的蒸发。单位时间内消耗的颗粒总数量随组装面积的增大而增加.通过调整悬浮液的蒸发温度和组装面积。可以有效地控制悬浮液相浓度的变化。从而实现在相浓度基本不变的情况下组装出高质量的聚苯乙烯胶粒晶体。
Evaporation self-assembly method, which is used to assemble sub-micrometer polystyrene microspheres, is presented in this paper. In this process the polystyrene microspheres are effectively assembled at the gas-liquid interface of suspension as moisture evaporates at fixed temperature. The scanning electron microscope shows that the three-dimensional colloidal assemblies have regular close-packed face-centered cubic structure. It was shown that the evaporation was blocked by the polystyrene colloid crystals growing at the gas-liquid interface, and the amount of the polystyrene mierospheres transferred to the colloid crystals from the suspension in unit time increased with the area of the assemblies. High-quality polystyrene colloid crystals can be assembled when not changing or decreasing the phase concentration, whose changes can be controlled by adjusting the assembly area and the evaporation temperature.