Plastics, a form of polymeric materials, break down after repeated use. One of the causes of this break-down is the rupture of chemical bonds of the polymers. Professor Esser-Kahn examines methods of using force or pressure to generate new bonds in plastic materials. These materials will be capable of capturing energy from an applied force or pressure and using it to initiate the growth of a polymer chain or the formation of a polymer network to strengthen the material. This project includes research and educational components to impact fundamental knowledge about polymer materials across the disciplines of chemistry and engineering. Outreach entails summer research training of high-school interns.
Jointly supported by the Macromolecular, Supramolecular and Nanochemistry Program of the Division of Chemistry and the Polymer Program of the Division of Materials Research, the Esser-Kahn research group is developing novel approaches that use the reaction of piezo-electric particles as a method to generate new bonds in polymeric materials. In one direction, the project investigates the piezo-reduction of a Cu(II) precursor to a Cu(I) activator that initiates the growth of polymer chain via atom-transfer radical polymerization. In a second direction, the piezo-generated Cu(I) is used to catalyze azide-alkyne cyclo-addition, creating new bonds between click chemistry handles. The research activities include 1) generation of novel reactions using piezo-mechanical reduction, 2) the growth of new polymer chains and types using piezo-ATRP, 3) the crosslinking of polymer gels using piezo-electric reactivity; and 4) the study and development of piezo-responsive materials and their mechanical characterization.
