Green Chemistry

Research Overview

A central thread of the DeSimone lab's early work was the use of supercritical and liquid carbon dioxide as a benign, recyclable replacement for the environmentally hazardous solvents that dominate the polymer and chemical industries. The lab demonstrated that highly fluorinated polymers, which were conventionally only accessible in ozone-depleting chlorofluorocarbon (CFC) solvents, could instead be synthesized by free-radical polymerization in homogeneous supercritical CO₂, establishing carbon dioxide as a viable medium for industrial polymer synthesis (Science, 1992). Building on this, the group developed the first dispersion polymerizations in supercritical CO₂, using amphiphilic stabilizers to carry out the polymerization of lipophilic monomers such as methyl methacrylate to high conversion and high molecular weight, yielding polymer microparticles in a CO₂ continuous phase (Science, 1994). To broaden the range of materials and processes that CO₂ could support, the lab designed molecularly engineered, "CO₂-philic" surfactants and demonstrated their self-assembly into micelles capable of stabilizing and dispersing otherwise CO₂-insoluble matter, laying the design principles for emulsion and dispersion chemistries in carbon dioxide (Science, 1996). These advances underpinned commercial green-manufacturing applications, including CO₂-based dry cleaning and precision cleaning.