New sustainable polymers with on-demand depolymerization property

To combat the crisis of today’s synthetic polymers arising from unsustainable production and disposal, it is essential for the synthetic polymer community to reshape the current polymer industry with sustainable polymers. As an emerging class of sustainable polymers, the development of chemically depolymerizable polymers (CDPs), which can undergo closed-loop depolymerization/repolymerization cycles to reproduce virgin polymers without the loss of properties from recovered monomers, offers an ideal solution to preserve finite natural resources, provides a feasible solution to the end-of-life issue of polymer waste, and thereby establishes a circular materials economy. However, two grand key challenges have been encountered in the establishment of practically useful CDPs: how to balance polymerization and depolymerization ability and how to unify conflicted depolymerizability and physical properties. Accordingly, this critical review article presents our vision for summarizing feasible strategies to overcome the above two significant challenges and the design principles for constructing an ideal CDP by highlighting selected major progress made in this rapidly expanding field.