Dr. Gary L. Gard

Professor of Chemistry Ph.D., 1964, University of Washington Email: gardg@pdx.edu Phone: 503-725-4274
Research
Dr. Gard's research is in material science that involves preparing new fluoro-compounds of theoretical and/or practical interest. Among potential uses for these compounds are insulating materials in high-voltage transformers, new surfactants, fluoropolymers, electrolytes for fuel cells and batteries, new organic superconductors, semiconductors, metals, and new oxidant systems. General Research in our group is focused on both the chemistry of oxidation~Wnew oxidative materials with high valent non-metals or high valent transition metal systems~Wand of fluorine~Wnew high performance fluoromaterials. Our fluorine investigations also overlap into the oxidation area because many oxidizing compounds are stabilized by fluorine or fluorine containing ligands. The ability of fluorine to play important roles in so many fields of chemistry is unique. Oxidation Chemistry We are interested in the preparation, stabilization, identification, and chemistry of new and unique oxidizing agents containing either nonmetals or transition metals. Our studies to date have included work with SF₅Cl, SF₅Br, XeF₆, CrO₂F₂, CrF₅, CrOF₃, CrOF₂, M₂CrO₂F₄, M₂CrO₂(CF₃COO)₄, M₂CrO₂(CF₃SO₃)₄, M₂MoO₂(CF₃COO)₄, M₂WO₂(CF₃OO)₄, U(SO₃F)₄, CrO₂FSbF₆, and (C₄N₂H₅)CrO₃CrO₃Cl. We have found that many of the chromium (VI) heterocyclic complexes prepared in our laboratories are effective and selective oxidants for a number of primary and secondary alcohols. New oxidant systems and their applications to environmental problems are of great concern to us. Fluorine Chemistry Research with organic fluorine compounds has shown that the incorporation of fluoro groups such as F, SF₅, SO₂F, and others, into carbon-containing moieties brings about significant physical, chemical, and biological changes. In many cases, new high-performance fluoroorganic materials are produced that exhibit outstanding behavior as new dielectrics (SF₅CF=CF₂), as new fluoropolymers [SF₅(CF₂CF₂)₁₆Br_0.3], as new fuel cell electrolytes [HO₃SCF₂CF₂CF₂SO₃H), as new stable superacids (SF₅CF₂SO₃H, SF₅CH₂CH₂SO₃H), as new solid state ionic conductors [SF₅CF₂SO₃Li, (CF₃SO₂)₂CHLi], as new organic superconductors [(ET)₂SF₅CH₂CF₂SO₃]. Our group has also been very successful in preparing novel fluorinated epoxides such as SF₅CFCF₂O and OCH₂CHCH₂OCF₂CF₂SO₂F, and novel fluorinated acrylates such as SF₅(CF₂)_nCH₂CH₂OC(O)CH=CH₂. We have observed an extensive chemistry for these epoxides. More recently, we have been preparing new surface films and multilayer polymer structures that are enriched with various perfluorinated groups. It is expected that these films will be useful in photonic/electronic systems as chemically resistant and thermally stable coatings and membranes. In addition to our preparative studies, we have been involved with a number of structural investigations; gas phase XPS and electron diffraction studies, and solid-state crystal studies. We are keenly interested in the effects of hydrogen bonding and/or fluorine bridging operating in these systems.
Representative Publications
Photopolymerized Acrylates Copolymer Films with Surfaces Enriched in Sulfur Pentafluoride (-SF₅) Chemistry, Chem. Mater., in press (1999). Recent Advances in Organosulfur Fluorine Chemistry - New Fluorinated Surface/Films Containing the SF₅ Group., Polymer Preprints, 39, 926 (1998). Pentafluoro-sulanyl(SF₅)-fluoroalkyl Iodides, R.J. Terjeson, J. Renn, R.Winter, G.L. Gard, J.Fluorine Chem., 82, 73 (1997). Photopolymerized Epoxide Copolymer Thin Films with Surfaces Highly Enriched with Sulfonyl Fluoride Groups, G.L. Gard, Chem. Mater., 8, 1475 (1996). Superconductivity at 5.2 K in an Electron Donor Radical Salt of Bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) with Novel Polyfluorinated Organic Anion, SF₅CH₂CF₂SO₃^-, U.Geiser, J.A. Schlueter, H.H. Wang, A.M. Kini, P.P. Sche, H.I. Zakowics, M.L. VanZile, J.D. Dudek, J.M. Williams, J. Renn, M.H. Whangbo, P.G. Nixon, R.W. Winter, G.L. Gard, J. Am. Chem. Soc., 118, 9996 (1996). Ion Conductivity and Scanning Calorimetry of Poly(ethylene oxide) Complexes of the Plasticizing Salt LiSO₃CF₂SF₅, M. Lerner, R. Nafshun, P. Nixon, N.N. Hamel, G.L. Gard, J. Electrochem. Soc. Letters, 142, 153 (1995). Functionalization of Pentafluoro-sulfanyl(SF₅) Olefins and Acetylenes, R. Winter, G.L. Gard, ACS Symp. Ser. 555, Inorganic Fluorine Chemistry: Towards the 21st Century, 128, (1994). New Polyfluoroalkoxysulfonyl Fluorides (Part VIII). Alcoholic and Polymer Derivatives, N.N. Hamel, G.L. Gard, J. Fluorine Chem., 68, 253 (1994).