Researcher(s)
- Maren Thompson, Chemical Engineering, Arizona State University
Faculty Mentor(s)
- Emil Hernandez-Pagan, Chemistry & Biochemistry, University of Delaware
- Joel Rosenthal, Chemistry & Biochemistry, University of Delaware
Abstract
Electrochemistry is a promising route for waste polymer up-cycling because it uses electricity to drive a reaction in place of potentially harmful or expensive catalysts and can be powered by renewable energy.
One application of electrochemistry would be to convert poly(acrylic acid), a superabsorbent polymer found in diapers, to poly(vinyl methyl ether), a plasticizer and tackifier used in adhesives. This conversion occurs via a non-Kolbe decarboxylation reaction which has previously been studied using RVC as the anode material.
This work investigates the effect of different anode materials to learn more about what drives the reaction. Surveyed anode materials included carbon, metals, and metal oxides in both their bulk and nanoparticle forms, with nanoparticles used to study the effects of electrode size. Nanoparticles synthesized for this project were characterized using XRD and TEM, and CV was performed to investigate the electrochemical properties of the materials.
2-methyl-3-phenylpropanoic acid was chosen as a model system due to ease of handling and characterization compared to the larger polymers. The resulting ether yields, determined by 1H NMR, showed nanoparticles performed better than their bulk counterparts and non-metals performed better than metals.
In the future, anode materials with a low yield of non-Kolbe products and little remaining starting material will be investigated for the Kolbe reaction pathway. Carbon-carbon bonds formed by Kolbe decarboxylation might act as crosslinks between polymer chains, modifying material properties and providing another avenue for electrochemically upcycling these polymers.