NSF Award
2404144
NON-TECHNICAL SUMMARY<br/><br/>This project seeks to develop the next wave of sustainable polymers, merging sustainability with material durability and practicality. A central objective is to overcome the current dichotomy within polymer science wherein recyclable and reprocessable materials often lack stability, while more robust ones lead to negative consequences because of their long-term environmental persistence. Through innovative design and precise molecular manipulation, this project aims to develop polymers that offer both long-term usability and innate reparability while maintaining their robust nature and resistance to solvents and high temperatures. The research will explore the critical molecular parameters of an underutilized chemical moiety that will govern polymer lifecycle—from synthesis to degradation—balancing processability with performance. The success of this project will lead to materials that require less frequent replacement, thereby reducing waste and promoting sustainability. Critical components of this project involve educational and outreach activities directed toward local students of all levels, as well as training and professional development of graduate and undergraduate students in emerging areas of chemistry and polymer science.<br/><br/><br/>TECHNICAL SUMMARY<br/><br/>The research focuses on four specific aims that collectively seek to expand the capabilities of covalent adaptable materials (CANs). Aim 1 investigates using pendent squarate esters as a novel dynamic exchange mechanism for CANs to improve the diversity of catalyst-free exchange chemistries for vitrimer materials. Aim 2 will explore the influence of pendent group squaramides on supramolecular polymer networks, aiming to understand how squaramides contribute to network properties and responsive behavior. The work in Aim 3 will combine squaramide and vinylogous urethane exchange to generate materials that are both dynamic-covalent and supramolecular, aiming to illustrate the enhanced properties that can be attained through straightforward methods. Aim 4 seeks to develop a new dynamic exchange approach through step-growth polycondensation, aiming to introduce unique exchange chemistry for CANs. The research employs a comprehensive set of molecular manipulations designed to elucidate fundamental structure-property relationships. The modularity of the approach provides a viable platform for understanding the roles of chain structure, topology, and functionality in the dynamic behavior of associatively crosslinked polymers. The scientific broader impacts of this research contribute to sustainability by designing polymers with longer life spans and recyclability. The work extends the benefits of dynamic networks to new exchange mechanisms, offering an alternative route to sustainable materials. The educational goals include this project serving as a training ground for the next generation of scientists. Students will acquire expertise in various synthetic and materials characterization methods, gaining a balanced understanding of both contemporary and foundational aspects of polymer science. A multi-pronged outreach program aims to foster excitement and broaden participation in science. The program includes research experiences with a focus on underrepresented minorities. By integrating scientific research with educational and outreach activities, the project aims to make a significant contribution to the field of polymer science while also addressing broader societal needs.<br/>.<br/><br/>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.
