ZINC-BASED CATALYST FOR SUSTAINABLE SYNTHESIS AND CHEMICAL RECYCLING OF POLYLACTIDE

Polylactide (PLA), a leading biodegradable and biobased polymer, represents a promising alternative to conventional plastics. However, despite its environmentally friendly properties, several sustainability challenges persist. Its industrial production relies on toxic tin-based catalysts, and its end-of-life management predominantly follows a linear economic model. Furthermore, the high cost of its monomer (lactide), which can constitute up to 50% of total production costs, limits PLA’s widespread adoption.[1] Consequently, the development of chemical recycling strategies for PLA waste has garnered significant interest due to their potential to enhance both environmental and economic sustainability by recovering the original monomer and producing valuable chemical derivatives.[2] In this work, we report a zinc-based phenoxy-imine pyridine complex as a highly efficient and versatile catalyst for both the Ring-Opening Polymerization (ROP) of lactide and the chemical recycling of PLA.[3] Under tunable reaction conditions, the catalyst enables selective depolymerization to lactide, or conversion via alcoholysis and hydrolysis to alkyl lactates and lactic acid, valuable green solvents and synthetic intermediates.[4]