A general strategy for access intrinsically antioxidant polyolefins

The long-term stability of various polyolefins relies on antioxidants. Traditional methods such as physical blending or chemical modification often suffer from non-uniform dispersion, migration, or lack of universality, especially for ultra-high molecular weight polyethylene (UHMWPE). Developing a general strategy to access various polyethylene types bearing intrinsically antioxidant properties (defined as polyolefins with antioxidant properties produced via polymerization, without postpolymerization antioxidant addition) remains a challenge. Here, we present a Catalyst-Enabled Antioxidation Strategy (CEAS) using phenolic hydroxy-functionalized dual-functional catalysts that both catalyze polymerization and provide antioxidant capacity, enabling the production of various types of intrinsically antioxidant polyolefins. We further develop enhancement strategies via auxiliary antioxidants and biomass-supported heterogeneous catalysis to boost antioxidant properties. This approach ensures uniform dispersion, overcomes processing limitations, retains mechanical properties, and enhances antioxidant performance. Notably, CEAS-synthesized UHMWPE demonstrates resistance to oxidation during demanding processing such as high-temperature spinning and radiation-induced crosslinking. Polyolefins require the addition of antioxidants to improve their stability during processing and lifetime. Here, the authors design catalysts containing phenolic units which impart antioxidant properties to the polyolefins, acting as both catalyst and antioxidant, leading to polyolefins with enhanced antioxidant performance.