Creep and drainage in the fast destabilization of emulsions

The destabilization of emulsions is important for many applications but remains incompletely understood. We perform squeeze flow measurements on oil-in-water emulsions, finding that the spontaneous destabilization of emulsions is generally very slow under normal conditions, with a characteristic time scale given by the drainage of the continuous phase and the coalescence of the dispersed phase. We show that if the emulsion is compressed between two plates, the destabilization can be sped up significantly; on the one hand, the drainage is faster due to the application of the squeezing force. On the other hand, creep processes lead to rearrangements that also contribute to the destabilization.

Automated summary

The destabilization of oil-in-water emulsions is usually slow under normal conditions, with the characteristic time scale determined by drainage of the continuous phase and coalescence of the dispersed phase. However, compressing emulsions between two plates can significantly speed up the destabilization process. This acceleration is due to faster drainage caused by squeezing force application and rearrangements from creep processes contributing to the destabilization.