CHAPTER 5: Emulsions Stabilized by Soft Microgel Particles

This chapter presents an overview of using soft, stimuli-sensitive microgel particles in controlling particle-stabilized emulsions. Unlike classical rigid solid particles, the unique properties of microgels such as softness, porous and in response to a variety of external stimuli give rise to special dynamic properties of interfacial layers, packing structure and emulsion stability. Today, microgel-stabilized emulsions are receiving growing attention in the scientific and industrial communities because the stimuli-responsive microgels allow us to prepare stimuli-responsive emulsions and thus enable emulsions to be prepared and broken on demand. Despite their rapidly increasing use, our fundamental understanding of the connection between special properties of microgels as stabilizers and emulsion characteristics is still surprisingly poor. This chapter outlines recent studies revealing the unique properties of microgel-stabilized responsive emulsions. In particular, effects such as solution temperature, pH, deformability of particles, and interface microstructure on emulsion stability will be discussed. Additionally, we will demonstrate that such microgel-stabilized emulsions can serve as a template for the fabrication of novel materials including Janus particles, microcapsules and porous materials, which have great potential for applications in catalysis and separation.