From Binding to Building: A Squaramide-Based Ion Pair Receptor as an Iniferter for Functional Polymer Synthesis

To address the challenge of developing the first squaramide-based ion pair receptor acting as an iniferter in the polymerization process, a well-known BDPA molecule with specific radical functions was incorporated into its structure. The developed ditopic receptor demonstrated the ability to cooperatively bind ion pairs. Moreover, it proved to be an effective iniferter in the polymerization reaction using methyl methacrylate. The polymerization process preserved the ion-binding properties of the receptor, enabling the formation of functional polymeric materials. It was shown that the resulting polymer with the embedded receptor can be used for salt extraction from both solid and liquid phases, whereas the reference receptor lacking the BDPA unit did not exhibit this capability. This opens new avenues for the design of intelligent and selective polymeric materials for applications in supramolecular chemistry and separation technologies.