Autodegradable Polymers:\nComplete Degradation without\nAny Trigger, Tunable Performance, and Biomedical Applications

Degradable polymers are an emerging research interest.\nThe innovation\nof new degradable polymers for biomedical applications is challenging\ndue to strict demands including nontoxicity of polymers and degraded\nproducts, complete degradation to avoid polymer residues in the body,\nand other suitable properties. Here, we demonstrate a series of degradable\npolymers for sustained-release drug applications synthesized by the\nalternating copolymerization of cyclic anhydrides and Schiff bases.\nIn addition to common feedstocks, the copolymerization is versatile\nand catalyst-free, affording polymers incorporating cyclic topologies\nand in-chain ester and peptoid groups. Particularly, the polymers\nexhibit self- and autodegradation without any trigger, which is distinct\nfrom remaining degradation mechanisms. The degradation performance\nis widely regulated by the polymer structure and external temperature,\nresulting in complete degradation from a few hours to several months.\nOwing to their unique properties, the polymers are approved for biomedical\napplications, as revealed soundly through cell viability assay, <i>in vitro</i> and <i>in vivo</i> drug release.