RUI: CAS: Bespoke Polymer Degradation via Topology and Sidechain Variation

Kenyon College, Gambier OH

Investigators

Abstract

With the support of the Macromolecular, Supramolecular and Nanochemistry (MSN) Program in the Division of Chemistry, Professor Yutan Getzler of Kenyon College will explore how polymer topology impacts the speed and pathways of polymer degradation. Polymers are ubiquitous, from the polypeptides in our muscles to the polyolefins of our packages. It is vital that we understand how the structures of these chemicals at the molecular scale impact their properties at the macroscale. Depending on how conditions such as temperature, catalyst requirements, and polymer composition impact depolymerization, this work may have implications in fields ranging from targeted drug delivery to biodegradable agricultural films. Furthermore, the depolymerization products have the potential for use as monomers in a circular polymer economy when paired with existing catalytic systems. Undergraduate researchers will gain critical preparation as early career scientists while pursuing these goals in a closely mentored environment and will participate in ongoing quarterly meetings with graduate research groups. This research project will provide an exceptional training opportunity for an early career scientist who desires greater research experience prior to pursuing a doctorate degree. Mentorship of this post-baccalaureate trainee will focus on the skills critical to success in graduate school – experimental design, data analysis, project management, near-peer mentoring, presentation, and writing. There are inherent challenges in synthesizing cyclic polymer topologies and so they remain relatively uncommon. The Getzler group designed a catalyst to help construct cyclic polyesters, a shape that is otherwise difficult to access. Due to the lack of chain ends, these macrocycles are protected from a common, uncontrolled, degradation pathway. By carefully modifying the monomers used to form the macrocycles, other unique degradation pathways may be enabled and controlled. In this research project, the Getzler group will synthesize and characterize a range of cyclic homopolymers and copolymers with different side-chain structures. The impact of topology and side chains on the polymer stability and depolymerization mechanism will be examined. An important goal of this research is to understand the factors that control depolymerization of cyclic polyesters. If successful, the fundamental knowledge gleaned from these studies will inform the rational design of materials with customizable degradation profiles. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.