Collaborative Research: Polar-Polyolefin Segmented Copolymers with Complex Architectures - Expanding the Scope of Polymeric Hybrid Materials

With the support of the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry, Professor Eva Harth at the University of Houston and Professor Krzysztof Matyjaszewski at Carnegie Mellon University aim to develop polymeric materials based on segmented polar-polyolefin copolymers with complex properties. These polymers can then assemble into nanostructures, such as spheres, cylinders or wormlike structures. These polymers are desired to advance energy storage materials and plastic material upcycling. This is made possible by the ability to precisely design and place molecular units along the polymer chains. Some of these are reactive units in non-polar plastic materials and others are for highly activated exchange reactions allowing the precise positioning of activators to further modify the material. Results of this research enhance the knowledge in how to combine normally incompatible polar and non-polar polymer chains to gain access to novel materials. The collaborators are actively engaged in undergraduate training and committed to graduate education, dissemination, and communication of the findings to educate the general public and develop the next generation of polymer scientists. Under this award, Professor Harth and Professor Matyjaszewski and their teams will further advance the unique radical/spin coupling methodology, the polyolefin active ester exchange process and developing novel polyethylene end-capping approaches to yield precision functional polyolefins from mono- and binuclear α-diimine Pd(II) complexes. These methodologies will be used to form di- and triblock architectures as well as star polymers with strategically positioned polyolefin and polyacrylic segments. The anchoring of suitable initiation units for controlled radical polymerization and modern atom transfer radical polymerization (ATRP) techniques such as regenerative ATRP with ppm Cu catalysts and benign reducing agents will be utilized and further developed to expand the range of monomers and techniques for polar poly(meth)acrylate - polyolefin block copolymer synthesis and self-assembly. Polyolefin macromonomers for ATRP will be investigated to form bottle brush architectures and combs. These collaborative approaches will not only make segmented polar polyolefin structures more attainable but also enable the exploration of novel architectures including stars, bottlebrushes, and other tailored nanostructures, which have previously been limited by the unavailability of suitable precursors. 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.