Emerging Applications of CO2-Based Polyurethanes: Bridging Material Sustainability and High-Performance Engineering.

Carbon dioxide-derived polyols (CO2-polyols), synthesized via the copolymerization of CO2 with epoxides, have emerged as a compelling sustainable alternative to petroleum-based polyols for polyurethane (PU) manufacturing, offering the dual benefit of sequestering waste CO2 and reducing reliance on fossil feedstocks. However, the carbonate linkages embedded within the CO2-polyol backbone impart a chain rigidity that alters intermolecular interactions and physico-mechanical behavior relative to conventional polyols, creating uncertainty over how CO2 incorporation translates into end-use performance and slowing industrial adoption despite clear environmental incentives. This review maps the diverse application frontiers of CO2-polyol-derived PUs. Specifically, we highlight their critical roles in adhesives, coatings, thermal stimuli- responsive shape-memory materials, waterborne PUs with enhanced hydrolytic and oxidative resistance, lithium-ion battery binders, and polyurethane foams. Across these systems, we describe how tuning the carbonate unit content and polyol functionality allows the rigidity, crosslink density, and thermal transitions of the resulting PUs to be precisely engineered, often matching or exceeding the performance of conventional counterparts while retaining a favorable sustainability profile. Collectively, this review provides a practical design framework to accelerate the transition of CO2-polyol-based PUs from laboratory-scale demonstrations to industrially viable, sustainable materials.