Highly‐Efficient Recycling of Poly(ethylene terephthalate)/Polyethylene Film through Low‐Temperature Methanolysis Catalyzed by Nonmetallic Deep Eutectic Solvent

While the poly(ethylene terephthalate) (PET)/polyethylene (PE) multilayer films find extensive applications, particularly in packaging, the recovery of single PE layer or high‐purity monomers from these films is seriously hindered by their complex compositions. Herein, a novel low‐temperature methanolysis strategy for the highly efficient recycling PET/PE multilayer films with nonmetallic deep eutectic solvent (DES) is developed, where PET can be depolymerized to dimethyl terephthalate (DMT) and ethylene glycol (EG) monomers at 115 °C and 0.45 MPa for 60 min with 100% PET conversion and up to 97.1% DMT yield while PE maintains its stability. The process flow for the high‐efficient recycling of PET/PE multilayer films is proposed, consisting of the methanolysis step and two solid–liquid separation ones to obtain the PE, DMT, and EG products. The process optimization, catalyzed mechanism, and swelling behaviors of DES for the PET methanolysis are studied. Finally, the kilogram‐scale experiments under best conditions also can obtain 100% PET conversion and 87.8% DMT yield with complete recovery of PE, which efficiently confirms scalability of the proposed recycling pathway. This work establishes a sustainable pathway for closed‐loop recycling of multilayer plastics by integrating PE material recovery with PET chemical upcycling.