Biomass‐derived Functional Polyacetals via Controlled Cascade Enyne Metathesis Polymerization: Tunable Degradability, Post‐Polymerization Modification, and Self‐assembly

We present a versatile platform for the synthesis of functional polyacetals from sugar and furfuryl alcohol derivatives using controlled cascade enyne metathesis polymerization. A range of monomers with defined stereochemistry were explored that featured broad functional group tolerance. The polymerization showed living character and permitted preparation of functionalized polyacetals with targetable molecular weights and more complex architectures. In addition, by harnessing the chiral nature of starting materials, the method granted facile access to chiral polyacetals. Modulation of regiochemical and substituent factors around the acetal motif conferred tunable hydrolysis rate, as well as photodegradability when installed with an ortho-nitrobenzyl group. The polymer structure was further elaborated by postpolymerization modification via leveraging the reactivity of suitable pendent groups and preparation of fully degradable bottlebrush polymers via graft-through polymerization. Further utilities of the method were showcased by the preparation of amphiphilic copolymers with complete degradability that exhibited self-assembly behaviors through copolymerization.