Degradation and utilization of polyvinyl chloride (PVC): Challenges and opportunities toward a circular economy

Polyvinyl chloride (PVC) poses persistent environmental and recycling challenges due to its high chlorine content, complex additives, and structural resistance to degradation. Recent research has shifted focus from traditional disposal methods toward chemically informed strategies that valorize PVC within the framework of a circular economy. This review systematically summarizes three emerging pathways for PVC transformation. The first involves catalytic deconstruction into small molecules such as chlorinated olefins, hydrocarbons, and oxygenates through thermal, photocatalytic, and electro-assisted processes. The second explores backbone-preserving reconstruction into functional materials including porous carbons, membranes, ion-conducting films, and vitrimer-type polymers by leveraging selective dechlorination and structural reprogramming. The third addresses the co-processing of PVC with mixed plastic wastes through synergistic catalytic systems that tolerate chlorine-rich streams and promote selective transformation. Across all pathways, emphasis is placed on structure–property correlations, chlorine management, additive compatibility, and downstream utility. Summary tables and schematic diagrams are included to compare system efficiencies, product selectivities, and application scopes. By integrating mechanistic understanding with materials innovation, this review highlights how PVC can be reimagined as a tunable molecular platform rather than a persistent pollutant.