Expansion and rupture of charged microcapsules

Sujit S. Datta, Alireza Abbaspourrad, David A. Weitz

Research output: Contribution to journalArticlepeer-review

4 Scopus citations


We study the deformations of pH-responsive spherical microcapsules - micrometer-scale liquid drops surrounded by thin, solid shells - under the influence of electrostatic forces. When exposed to a large concentration of NaOH, the microcapsules become highly charged, and expand isotropically. We find that the extent of this expansion can be understood by coupling electrostatics with shell theory; moreover, the expansion dynamics is well described by Darcy's law for fluid flow through the microcapsule shell. Unexpectedly, however, below a threshold NaOH concentration, the microcapsules begin to disintegrate, and eventually rupture; they then expand non-uniformly, ultimately forming large, jellyfish-like structures. Our results highlight the fascinating range of behaviors exhibited by pH-responsive microcapsules, driven by the interplay between electrostatic and mechanical forces.

Original languageAmerican English
Pages (from-to)92-95
Number of pages4
JournalMaterials Horizons
Issue number1
StatePublished - Jan 2014
Externally publishedYes

ASJC Scopus subject areas

  • General Materials Science
  • Mechanics of Materials
  • Process Chemistry and Technology
  • Electrical and Electronic Engineering

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