Supercritical Fluids

Abstract

Supercritical fluids have been intensively studied during the past three decades in polymer science. The main driving force has been the substitution of the large amount of liquid organic solvents, currently used by the polymer industry, to design more sustainable, environmental friendly, polymer‐related processes. Their key characteristic is the ability to tune their physical and chemical properties by simply changing the temperature and/or the pressure. Research focused not only on the development of supercritical fluid reactions but also on the phase behavior of supercritical fluids with polymers and the mathematical modeling of such reaction systems. As far as polymerizations are concerned, a wide range of homogeneous and heterogeneous, including catalytic, reactions have been investigated and many analytical methods were applied to monitor the evolution of these reactions and fundamentally understand them. Finally, a very large part of the research carried out has been devoted to using supercritical fluids in polymer processing. As a result, many processes of polymer fractionation, impregnation, purification, foaming, particle formation, and extrusion have been developed for an extremely wide pallet of applications, such as medical devices, implants, space‐vehicle parts, specialty chemicals, and many others.