Supercritical Infusion

Certain inorganic crystalline materials can be infused into organic or polymeric substrates in a supercritical fluid medium. Further, organic ingredients that are insoluble in the substrate can also be infused similarly using a supercritical fluid medium. Such a process is quite significant, when a temperature sensitive ingredient has to be added into other substrate, such as polymeric resin or film. Infused products are superior in quality and desired functions, compared to melt-processed counterparts which are prone to have annealed, fused, and agglomerated morphology. Application fields are quite broad from pharmaceuticals, biomedical applications, multifunctional films, adding colorants or tints to the finished goods, controlled release materials, etc. The process can also be readily modified as encapsulation. Lee’s original work in collaboration with IMET Corporation and Northern Technologies International has received a couple of U.S. patents [7,217,749 and 7,217,750].

Lee’s graduate student team has investigated and elucidated the mechanic steps and processes of supercritical infusion of salt crystals into thermoplastic polymer resins and preformed films. The effectiveness of supercritical infusion process was demonstrated in terms of the final product quality in desired functions, lower temperature processing, uniform dispersion, reduction in raw material cost, etc. A wide range of applications are being studied for manufacturing multi-functional value-added superior-quality materials