Polyethylene materials with in-chain ketones from nonalternating catalytic copolymerization

Polyethylene with a nickel’s worth of CO The biggest problem with polyethylene, the most abundantly manufactured plastic, is that it doesn’t break down easily once it is discarded. Chemists have long sought to introduce small quantities of carbon monoxide (CO) into polyethylene chains to promote photodegradation, but too much CO tends to jump in and spoil the plastic’s other properties. Bauret al . report that nickel catalysts coordinated by bulky phosphinophenolate ligands can catalyze ethylene polymerization with approximately 1% CO incorporation, preserving tensile strength while promoting degradation under ultraviolet exposure (see the Perspective by Sobkowicz). —JSY