Engineering Functional Polymer Networks: A Critical Review of Ion Exchange Resins for Selective Separation, Catalysis, and Environmental Applications

ABSTRACT This review provides a critical and exhaustive analysis of the Purolite resin portfolio, positioning it as a high‐precision technological platform for advanced separation and chemical conversion processes. Moving beyond their historical application in conventional water treatment, these polymeric materials have evolved into sophisticated molecular architectures, encompassing strong acid cation (SAC) and strong base anion (SBA) exchangers, high‐affinity chelating resins, and specialized enzymatic supports. The study first evaluates the decisive influence of matrix morphology contrasting gel‐type and macroporous structures on active site accessibility and diffusional constraints. Subsequently, the fundamental mechanisms governing adsorbate‐resin interactions are elucidated through the lens of thermodynamic equilibrium models and advanced spectroscopic characterization, including XPS, Raman and EXAFS. Particular emphasis is placed on emerging frontiers, such as the sequestration of per‐ and polyfluoroalkyl substances (PFAS), the selective recovery of uranium and rare earth elements, and the deployment of heterogeneous enzymatic catalysis for biofuel synthesis. Finally, the integration of life cycle assessment and techno‐economic indicators underscores the industrial scalability and sustainability of these functional materials in addressing the contemporary challenges of green chemistry and the global ecological transition.