cis-Fused cyclohexane promoted the chemical recycling of polycarbonate to monomer

The development of chemically recyclable polymers serves as a promising strategy to solve the plastic pollution issue. In this contribution, we prepared a seven-membered cyclic carbonate with a cis-fused cyclohexane structure (C6DO). Ring-opening polymerization of this monomer afforded the aliphatic polycarbonate P(C6DO) with high molecular weight and narrow polydispersity. Copolymerization of C6DO with L-lactide (L-LA) allowed access to a series of random copolymers with various C6DO compositions. Changing the C6DO content in the copolymers led to fine-tuning of the thermal and mechanical properties of the resulting copolymers. The amorphous P(C6DO) displayed excellent ductility, with an elongation at break of 423.41 ± 39.22%. Remarkably, copolymer P[(C6DO)₈₀₀-co-(L-LA)₂₀₀] demonstrated a tensile strength at break of 10.88 ± 1.08 MPa and elongation at break of 336.78 ± 46.13%. More importantly, P(C6DO) could be effectively and selectively depolymerized into the corresponding monomer C6DO, establishing a circular plastic economy.