Sequential Postpolymerization Modification of CO2-Based Polycarbonates via Click Chemistry and Kabachnik–Fields Reaction

CO2-based polycarbonates represent an important class of sustainable polymers derived from carbon dioxide utilization. However, the inherent absence of functional groups hinders the use of these materials in high-value applications. To address this challenge, we combined click chemistry with the Kabachnik–Fields reaction for sequential postpolymerization modification of CO2-based polycarbonates. This strategy not only introduced biobased multifunctional pendants along the polycarbonate backbone but also enhanced the mechanical strength, thermal stability, flame retardancy, and hydrophilicity of the resulting films. Notably, the incorporation of α-aminophosphonate via the Kabachnik–Fields reaction imparted the resulting polymers with unconventional fluorescence and typical aggregation-induced emission (AIE) characteristics. This work provides a general and robust strategy for the rational design of functional aliphatic polycarbonates toward practical applications.