Related Experiment Video
Updated: Apr 24, 2026

Fabricating High-viscosity Droplets using Microfluidic Capillary Device with Phase-inversion Co-flow Structure
Published on: April 17, 2018
Cavitation in drying droplets of soft matter solutions
Fanlong Meng1, Masao Doi2, Zhongcan Ouyang3
1State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190, China and Kavli Institute for Theoretical Physics China, Beijing 100190, China and Center of Soft Matter Physics and Its Applications, Beihang University, Beijing, China.
Abstract:
When a droplet of a soft matter solution is dried, cavities are often formed in the droplet, giving a hollow sphere in the end. A theoretical model is given for this phenomenon. It is shown that the formation of a gel-like layer (skin layer), which has a finite shear modulus, is essential for the phenomenon to take place. The condition for cavity formation (how it depends on the shear modulus and thickness of the skin layer), and the variation of the droplet volume and cavity volume after the cavity formation are examined.
Related Concept Videos
Vapor Pressure Lowering
Phase Transitions: Vaporization and Condensation
Entropy and Solvation
Colloidal precipitates
Aqueous Solutions and Heats of Hydration
When ionic compounds dissolve in water, the ions in the solid separate and disperse uniformly throughout the solution because water molecules surround and solvate the ions, reducing the strong electrostatic forces between them. This process...
Theories of Dissolution: Diffusion Layer Model
This process starts with a thin layer, saturated with the drug, forming at the interface between the solid and liquid. The solute then diffuses from this layer into the main solution. The Noyes-Whitney equation suggests that the rate of dissolution relies on the diffusion...

