Degradable polymers via controlled alternating ring-opening metathesis copolymerization of bio-sourced oxa-norbornenes and 2,3-dihydrofuran

To mitigate the environmental footprint of the polymer industry, developing sustainable and eco-friendly bio-based polymers has become imperative. Herein, we report the synthesis of degradable, bio-based copolymers via the alternating ring-opening metathesis polymerization (ROMP) of biomass-derived oxa-norbornenes (synthesized from itaconic anhydride and furfuryl alcohol) and 2,3-dihydrofuran (DHF). Under optimized conditions, the polymerization proceeded in a controlled manner, yielding predictable molecular weights from the monomer-to-initiator feed ratio and enabling block copolymer synthesis. The unsymmetrical oxa-norbornene monomers underwent ring-opening with moderate regioselectivity. DFT calculations revealed that this selectivity is governed by kinetic control. The thermal and mechanical properties of the copolymers were also investigated. Furthermore, the copolymers underwent degradation under acidic conditions to yield small molecules derived from the original monomer segments. This work establishes a versatile strategy for producing bio-derived, degradable polymers with potential for sustainable applications.