Emulsions

Emulsions is a field between science and art. This chapter presents some basic definitions and looks at some applications. It discusses the most important property of emulsions, the stability, the factors that affect it, and how people can manipulate (influence) the stability of emulsions. Emulsions are metastable and there are several destabilization mechanisms, which may need to be considered depending on the emulsion type, application and expected lifetime. The most important mechanisms are creaming, flocculation or coagulation, and coalescence/breaking. Adding polymers can result in both stabilization and destabilization of colloidal systems. The DLVO theory can, in many cases, be used to analyse stability of emulsions. The steric stabilization is often used in the emulsion field. The chapter covers phase inversion temperature (PIT) which occurs for thermodynamic reasons. Finally it discusses use the HLB factor as a quantitative design tool in emulsion science.