Crafting Tunable Hollow Particles Using Antisolvent‐Driven Interlocking of Micron‐Sized Building Blocks

Abstract

The contribution of a hollow structure on the rheological behavior of granular suspensions remains un‐investigated due to the challenge of water impermeability. Here starch is used to fabricate water‐permeable hollow particles, as a model for granular suspensions and investigated the resulting microstructures and rheological behavior. The hollow structure is fabricated based on a bottom‐up method by assembling micron‐sized building blocks into a superstructure. A Pickering emulsion is heated to fuse the starch interface, then, upon antisolvent precipitation, the polymer strands interlock to form a rigid shell around the oil template. When the template is removed a hollow particle remained. These particles exhibited a specific volume >5‐times higher than unmodified starch and consequently a higher viscosity. Larger particles showed higher viscosity but are also more fragile. The template structure can be manipulated to fine‐tune their functionality. These micro‐sized building blocks made from edible materials can be used as the next generation of texturizers. Additionally, these water‐permeable colloidosomes present an innovative approach to understanding how micro‐architectures impact the rheological behavior of granular suspensions.