MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China.
Langmuir. 2012 Mar 20;28(11):5010-6. doi: 10.1021/la3003299. Epub 2012 Mar 9.
The deformation and recovery behaviors of multilayer microcapsules were investigated after being forced to flow through a microchannel. The microchannel device with a constriction (5.7 μm in depth) in the middle was designed, and the multilayer microcapsules with different size and layer thickness (and thereby different mechanical strength) were used. Deformation in the microchannel was observed for all the capsules with a size larger than the constriction height, and its extent was mainly governed by the difference between capsule size and constriction height. The squeezed microcapsules could recover their original spherical shape when the deformation extent was smaller than 16%, whereas permanent physical deformation took place when the deformation extent was larger than 34%. The capsules filled with polyelectrolytes could greatly enhance their shape recovery ability due to the higher osmotic pressure in the capsule interior and could well maintain the preloaded low-molecular-weight dyes regardless of the squeezing.
研究了多层微胶囊在被迫流经微通道后的变形和恢复行为。设计了具有中间收缩（深度为 5.7μm）的微通道装置，并使用了不同尺寸和层厚（从而具有不同机械强度）的多层微胶囊。对于所有尺寸大于收缩高度的胶囊，都观察到了在微通道中的变形，其程度主要由胶囊尺寸和收缩高度之间的差异决定。当变形程度小于 16%时，被挤压的微胶囊可以恢复其原始的球形形状，而当变形程度大于 34%时，则会发生永久的物理变形。填充了聚电解质的胶囊由于胶囊内部的渗透压更高，因此能够大大增强其形状恢复能力，并且无论挤压如何，都可以很好地保持预加载的低分子量染料。
