A review on catalytic copolymerization of carbon dioxide and epoxides

Abstract

The catalytic copolymerization of carbon dioxide (CO₂) and epoxides represents a paradigmatic strategy for carbon valorization, simultaneously addressing the imperative of greenhouse gas mitigation and the sustainable production of advanced polymeric materials. As an inherently atom-economical and energy-efficient transformation, this process affords aliphatic polycarbonates (PCs) with tunable architectures and high CO₂ incorporation, offering significant environmental and industrial benefits. However, the intrinsic thermodynamic stability of CO₂, alongside the kinetic inertness of epoxides, necessitates the development of highly active, selective, and robust catalytic systems capable of suppressing side reactions such as cyclic carbonate and polyether formation. This review critically examines the evolution of heterogeneous and homogeneous catalytic platforms, including well-defined metal complexes, multinuclear architectures, and emerging organocatalytic systems, unpacking the intricate interplay between electronic effects, steric modulation, and cooperative mechanisms in catalyst design. Furthermore, this review elucidates current limitations in catalyst stability, process scalability, and impurity tolerance, proposing forward-looking strategies such as dynamic ligand frameworks, heterobimetallic pairing, and macromolecular catalyst architectures to overcome these bottlenecks. By integrating mechanistic insights, material performance considerations, and sustainable process engineering principles, this contribution aims to the rational design for next-generation catalytic systems in CO₂-based polymer chemistry.