Our research is in the area of organic/polymer synthesis.  We aim to develop synthetic pathways leading to architecturally interesting macromolecules, such as monocyclic and bicyclic polymers, star polymers, and other structures.  To accomplish this, we rely on post-polymerization reactions that join polymer chains together.  Much of our focus is the mechanistic study and optimization of these reactions, which might be done by radical-radical coupling, trapping chain ends with radicals, “click” chemistry, or nickel-catalyzed reductive coupling.  Below is a sequence leading to C-C bond formation between two polymer chains.

The scheme above illustrates the combination of traditional organic synthesis applied into our polymer chemistry research agenda.  We have recently published papers describing this new system, and hope to expand its utility into new polymeric types and structures, and also into polymer synthesis.

Research students in my group must learn how to make a linear polymer and characterize it.  We most often use reactions known as “atom transfer” reactions, specifically applied to polymer chemistry.  This is called “atom transfer radical polymerization”, and is summarized below, along with the closely related “atom transfer radical coupling”.

Note that the atom being transferred is bromine, and a ligand-bond copper catalyst allows for this transfer.  This is a redox reaction, with the copper being oxidized and the alkyl bromide end group of the polymer being reduced.  As a consequence of this mechanism, the polymer ends up with a bromo end group which is essential to our group’s post-polymerization manipulations.

This is just a basic overview of our research, and we are interested in other topics as well.  Please reach out for more details.