Catalyst design strategies for solventless chemical recycling of Nylon-6

Finding sustainable methods for the cyclodepolymerization of polymers, such as Nylon-6, is a critical target to address growing accumulation of these materials. In this issue of Chem, Marks and coworkers present an effective catalyst system using an yttrium ansa-metallocene catalyst for the efficient and solvent-free cyclodepolymerization of Nylon-6. Finding sustainable methods for the cyclodepolymerization of polymers, such as Nylon-6, is a critical target to address growing accumulation of these materials. In this issue of Chem, Marks and coworkers present an effective catalyst system using an yttrium ansa-metallocene catalyst for the efficient and solvent-free cyclodepolymerization of Nylon-6. Catalyst metal-ligand design for rapid, selective, and solventless depolymerization of Nylon-6 plasticsYe et al.ChemNovember 30, 2023In BriefNylon-6 is an extraordinarily robust material that lacks biodegradability, leading to persistence and accumulation in the environment. In this mechanism-oriented catalysis study, we design an efficient, tunable metallocene catalytic system using abundant metals, achieving a record Nylon-6 depolymerization rate with ≥99% yield of re-polymerizable ε-caprolactam. This solventless process operates with a minimal 0.04 mol % catalyst in a model continuous process. These catalysts and processes are compatible with depolymerizing diverse commodity Nylons, such as fishing nets, carpets, clothing, and plastic mixtures. Full-Text PDF