Guest Speaker – Poly/Mat (CHEM 721) – April 13, 2023

Bio
Johnathan Brantley completed his B.S. degree in chemistry at Western Kentucky University in 2010, after which he moved to the University of Texas, Austin for his graduate studies. As an NSF predoctoral fellow in Christopher Bielawski’s laboratory, John explored how mechanical force can control chemical reactivity in polymers. After completing his Ph.D. in 2014, John joined Dean Toste’s group at the University of California, Berkeley. As an NRSA postdoctoral fellow, he explored the synthesis and reactivity of trifluoromethyl iodonium salts. John joined the Department of Chemistry at the University of Tennessee, Knoxville in 2017, where he is currently an Assistant Professor.

Abstract
The exploration of unique architectural elements is critical for advancing our fundamental understanding of polymer structure-property relationships and accessing next-generation materials. As such, expanding the range of functional groups that can be incorporated within polymers is paramount for developing advanced soft materials. The precise installation of reactive motifs, in particular, could be leveraged to access tunable (or otherwise functional) polymers with bespoke properties. Here, we will explore a variety of novel materials that are decorated with underutilized functional groups in materials science. For example, cumulenes are valuable synthetic handles that are largely absent from macromolecular architectures. Metallocarbenes, which participate in numerous chemical transformations, are also underexplored functional groups in polymer chemistry. We found that both motifs could be incorporated into polymers with good fidelity, and the resultant materials exhibited various stimulus-responsive behaviors (e.g., network formation or CO release). We will also explore how new methodological developments can enable iterative modifications to realize functionalization and/or degradation of various polymers. For example, Suzuki chemistry can be harnessed to decorate polymers with reactive aryl aldehydes (which can undergo an array of subsequent modifications). Conversely, electrochemical editing of polymers (via radical cation pathways) can open new opportunities for polymer degradation and/or functionalization.