Functionalized Magnetic Nanoparticles as Polymerization Catalysts

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AbstractProposal Title: Functionalized Magnetic Nanoparticles as Polymerization CatalystsProposal Number: CTS-0553554Principal Investigator: Christopher W. JonesInstitution: Georgia Tech Research Corporation GA Institute of TechnologyThe advent of single site, homogeneous polymerization catalysts based on discrete transition metal complexes has produced a revolution in the field of polymer chemistry. Despite all the successes of these new catalysts, they are hampered by one common problem that all homogeneous polymerization catalysts share they are difficult to remove from the product polymer. In some cases, this places severe limitations on this new technology for examples in biomedical applications. Magnetic nanoparticles (10-50 nm in diameter) have great potential for use as solid supports for catalysts in polymerization processes. The extremely small particle size of the material gives a large external surface area to volume ratio allowing for an enormous catalytic active site density all on the external surface of the solid, eliminating all intra-particle diffusional limitations that hamper porous solids as catalyst supports. Furthermore, the magnetic capability of the nanoparticulate support provides a way for simple and efficient recovery of the catalysts through the use of an applied magnetic field, potentially allowing for the preparation of polymers that are free of residual metal. Spinel ferrite nanoparticles offer an excellent platform for design and control of magnetic properties to satisfy these criteria. In particular, the cobalt spinel ferrite system (Co1-xMxFe2O4 with M = Mg or Zn and X = 0 1), offers a variety of potentially useful supports, as the magnetic properties of the spinel ferrite nanoparticles can be altered by chemical means and their properties can be optimized for specific applications. Spinel ferrite magnetic nanoparticles are to be functionalized with silanes to immobilize polymerization catalysts where catalyst recovery might be beneficial. In particular, lactone polymerization catalysts are a key focus. It is anticipated that the nanoparticle supports will be ideal for many other types of immobilized catalysts as well, not just polymerization catalysts. Nearly all commercial consumer products have plastics and polymers as key components in their construction. Thus, this project, in offering a potentially new technology platform for polymerization catalysis, has the possibility to broadly impact myriad different fields. The multi-disciplinary project brings together several key technology areas including nanotechnology, spectroscopy, surface chemistry, coordination chemistry and polymer science. Hence, it will greatly broaden the technical backgrounds of the graduate students involved, with the close interactions among graduate students in chemistry and chemical engineering offering the invaluable experience of working in a multidisciplinary team environment just as in a typical modern industrial research and development laboratory. The results from this research will trickle into Georgia Institute of Technology's newly initiated and evolving campus-wide courses on nanotechnology at both graduate and undergraduate levels, in which both PIs are playing key roles.