CAREER: CAS: Structured Assemblies of Block Copolymers and Macrocycles with the Novel Halogen Bond

Oakland University, Rochester MI

Investigators

Abstract

With the support of the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry, Ngong Kodiah Beyeh of Oakland University in Rochester, Michigan, will develop a novel approach that combines supramolecular chemistry and polymer science to assemble polymeric structures that consist of organic macrocycles with persistent internal cavities. Analogous to the widely researched “hydrogen” bonds that play important roles in many natural and synthetic systems, “halogen” bonds could serve as recognition sites holding together the components in complex structures, but they are less explored. This project will provide new fundamental knowledge on the roles of halogen bonds and investigate the properties of this new class of functional polymers. The internal cavities of these porous structures may serve as recognition sites for sensing, uptake, separation, or storage of specific guest molecules, e.g., methane and carbon dioxide. The reversible formation of halogen bonds bestows self-healing properties and the possibility of recycling. This project will also incorporate educational training and mentoring of the next generation of a diverse workforce in science and technology. The multidisciplinary nature of this project ensures that students, including high school students, will develop broad skills in both organic and materials chemistry. Student participation in the project, including workshops and colloquia focusing on career options, will foster their pursuit of careers in science. An important objective of this project is to fully elucidate the capabilities and properties of halogen bonds as recognition "sticky" sites in the assembly of functional polymeric structures. Dr. Beyeh and his students will synthesize several libraries of resorcinarene macrocycles and block copolymers. The resorcinarene macrocycles, which provide persistent internal cavities for guest binding, will be decorated with functional groups to form halogen-bonds with different block copolymers. The halogen-bonded hybrid structures will be fully characterized. The halogen-bonding properties, stability, and self-healing efficiency of these hybrid structures will be studied. Their morphology, porosity, and guest-uptake properties will be evaluated. If successful, this project will provide new fundamental knowledge on the roles of halogen bonds and their properties in building new classes of functional polymers. 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.