High-throughput computational analysis of kinetic barriers to ring-closing depolymerization for aliphatic polycarbonates

The chemical reversion of polymers via ring-closing depolymerization (RCD) to their monomeric constituents is a highly promising avenue to enable end of life-cycle recycling and reuse. However, most reported systems using RCD revolve around bespoke monomer designs to facilitate facile depolymerization and there exists relatively few investigations into influence of functional groups on the ability of a particular monomer to cleanly undergo depolymerization. Here, we perform computational investigations into the energy barriers for RCD of 6-membered aliphatic carbonates in different solvents. The results demonstrate highlight clear trends observed in prior experimental studies, validating the utility of computational investigations towards understanding RCD. Experimental evaluation of thermal depolymerization of two monomers confirmed the ability of the computationally investigated monomers to cleanly undergo RCD. Overall, this work highlights the utility of high-throughput energy barrier computations to provide meaningful insight into broad reactivity trends that would be highly laborious to access experimentally.