A significant amount of abandoned plastics has caused serious harm to the environment and ecosystems. The urgent demand for carbon‐neutral technology has driven the effective recycling of plastic waste. Various chemical approaches have been extensively explored for plastic waste management, with recycling strategies aimed at selectively producing high‐value products garnering increasing attention. Notwithstanding considerable progress, each treatment method possesses certain constraints. Multi‐step cascade coupling offers a viable strategy for efficient plastic recycling, affording enhanced selectivity towards desired products. This review provides a systematic review of the reaction mechanisms and representative studies of pyrolysis, photocatalysis and electrocatalysis for various types of plastics. A strategy centred on the design of specific intermediate molecules enables a polymer conversion pathway where depolymerisation into monomers, oligomers or other intermediates is followed by their selective transformation into high‐value chemicals. Uniting established methods like thermal degradation and solvolysis with emerging fields—including photocatalysis, electrocatalysis and biotransformation—this review proposes a coherent framework for the rational design of multi‐stage or cascade plastic recycling processes. This approach paves the way for the efficient transformation of abandoned plastics into valuable chemicals.
Tang et al. (Thu,) studied this question.