Synthesis and Characterization of Asymmetric A1BA2 Supramolecular Triblock Copolymers via Noncovalent Interactions: A Solution and Solid-State Study

We present the design, synthesis, and characterization of triple hydrogen-bond-forming precursors and their supramolecular triblock copolymers. Thymine end-functionalized polystyrene-b-polyisoprene (PS-b-PI-Thy) and diaminotriazine end-functionalized polystyrene (PS-DAT) were successfully synthesized via anionic polymerization followed by suitable organic reactions and then solution-mixed to form supramolecular triblocks via hydrogen-bonding interactions. Three different types of asymmetric A1-b-B-sb-A2 supramolecular triblock copolymers were prepared by varying the molecular weight of the A1-b-B diblock copolymers and A2 homopolymers. Proton nuclear magnetic resonance spectroscopy was used for the detailed structural characterization of the polymers in solution, and gel permeation chromatography was used to determine the molecular weight and polydispersity index of all homopolymers and block copolymers. Additionally, transmission electron microscopy and small-angle X-ray scattering measurements were employed to assess the solid-state morphological structures of the supramolecular triple hydrogen-bond triblocks, the diblocks, and single hydrogen-bond mixtures of diblocks with homopolymers.