Grant: Discovery Grants Program - Individual

<p>The research proposed herein aims to systematically develop the chemistry of phosphorus and its compounds. Phosphorus is an important element, not only being essential for life but being used in a wealth of commercial products. The primary objective of our work is to develop polymers that contain phosphorus as a key component of the main chain. The properties and potential applications of a particular polymer are a direct consequence of the arrangement and type of atoms that make up the chain structure. Most polymers in use today are comprised of chains containing carbon, oxygen, and/or nitrogen atoms in well-defined sequences. The development of polymers composed of other elements is at its infancy, however, there is considerable promise for these so-called inorganic polymers due to their unique physical properties and chemical functionality. For example, the commercial polymer silicone, consisting of alternating silicon and oxygen atoms, has extreme flexibility and temperature stability that is unattainable with organic polymers. The key challenge to inorganic polymer development is the lack of general synthetic routes to incorporate inorganic elements into long chains.<br /> <br /> The addition polymerization of the C=C bond of olefins is perhaps the most important method of industrial polymer production being used to make polyethylene, polypropylene polystyrene, acrylics, and Teflon, to name a few. It was long believed that heteroatom-containing multiple bonds were not suited for addition polymerization methods. We have shown that the addition polymerization of the P=C bond in a phosphaalkene is a route to phosphorus-containing polymers. This is a subject that will be rigorously pursued during the next five years. The mechanism of this new polymerization reaction is still in question and our proposed investigations are outlined herein. We will also explore the synthesis of chiral phosphaalkenes that may be employed directly as ligands for transition metal-catalysis and small-molecule activation or as monomers to afford polymeric ligands for use in polymer-supported catalysis. In a final area of pursuit, we propose to develop new types of p-conjugated phosphorus-containing polymers that exploit the chemical functionality of phosphorus as a means to tailor the electronic properties for application in areas such as small molecule sensor materials.<br /> <br /> In closing, the work proposed herein further expands the fascinating chemistry of phosphorus. This work will lead to gains in fundamental knowledge of inorganic chemistry and polymer science, and will provide a foundation for future technological applications.</p>