Microgel applications and commercial considerations

The term microgel has been used to describe a variety of particles that differ substantially in structure, physicochemical properties, preparation and application and has been used interchangeably with terms such as nanogel, microsphere and macrogel. Many excellent and wide-ranging reviews have been published on the numerous particle types considered to fall within the broad sphere of nano-/microparticles. The aim of this review is to focus on applications of microgel particles that are synthesised by polymerisation, are of colloidal size and exhibit conformational changes in response to changes in environmental conditions. It is not the intention to attempt to cover every potential microgel application; instead, a selected range of areas will be covered and the commercial implications of scaling up the production of microgels for such purposes will be discussed. A brief description of the characteristics of microgel particles is followed by discussion of applications such as enhanced oil recovery, biomaterials and catalysis, before issues of commercialising microgel production are considered.