Assembly of Novel Branched Ionic Polymers: Chirality Induction and 2D Heterostructures

NON-TECHNICAL SUMMARY Ionic polymers (materials made of long molecular chains with ion-containing groups) possess unique internal morphologies guided by intermolecular and interfacial interactions of ionic groups and conductive properties for a wide range of applications. These materials will be studied here, as well as related branched polyelectrolytes, for which inter- and intra- molecular interactions resulting from the abundant ionizable groups can be further utilized to control the polymer morphology, shape, and conductivity. Specifically, the chiral helical organization of synthetic branched macromolecules and organized two-dimensional nanomaterials, which will be synthesized and studied in this project, are of potential interest for novel composite materials and advanced applications involving energy storage, energy conversion, and related energy saving. Among potential future science and engineering applications of these ionic polymeric composite materials are flexible, lightweight solid and liquid electrolytes for advanced wearable batteries and powerless devices for improved human performance and well-being. TECHNICAL SUMMARY This project is focused on branched ionic polymers with multiple functionalities and chiral branched polyelectrolytes and 2D heterostacks organized across multiple lengthscales from individual macromolecules to multicomponent assemblies and shape-persistent materials. First, weak ionic interactions or covalent bonding of terminal chiral groups will be exploited to induce novel helicoidal organization of chiral nematic type in branched polymer micellar solutions and upon self-assembly on different substrates and nanostructures. Second, co-assembly of ionic polymers and functionalized 2D materials such as MXenes with complementary functionalities will be explored for stacked organic-inorganic heterostructures and Janus star polymers with multiple functionalities. The research will impact our understanding of directed co-assembly of multi-phase ionic polymers with functionalized nanosheets and advance the field of novel organic-inorganic functional nanocomposites with special ordering and properties. . This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.