CBE Colloquia  - Bottom-up Design and Synthesis of Functional Polymeric Materials via Dynamic Covalent Chemistry

Dynamic covalent chemistry (DCvC) has proven to be highly effective toward the construction of well-defined molecular and polymeric architectures. The error-correction mechanism enabled by the reversible formation of dynamic covalent bonds leads to the formation of structurally ordered, thermodynamically favored species. One such example is the solvothermal synthesis of covalent organic frameworks (COFs) with periodic structural order and low defect density. The chemical compositions of such frameworks are usually well-defined and inter-monomer connectivity (covalent bonding) is robust. Bottom-up synthesis of covalently linked polymers through DCvC has many critical advantages, such as easy tunability of functional and structural properties in a controlled fashion through rational design of the precursors, formation of highly stable linkages, minimized structural defect, and possible access to sophisticated architectures that are hard to obtain otherwise. This talk will focus on our recent progress in the development of three types of DCvC, namely alkyne metathesis, spiroborate exchange and dynamic nucleophilic aromatic substitution (DySNAr). These powerful synthetic tools enabled the bottom-up design and synthesis of novel polymeric materials, such as unprecedented single-crystal DNA-like helical covalent polymers (HCPs), a novel carbon allotrope, and closed-loop recyclable thermosets.