Precision Pseudo-Polysaccharides via Chain-Growth Polymerization of Sugar-Based Monomers

About This Grant

With the support of the Macromolecular, Supramolecular, and Nanochemistry Program in the Division of Chemistry, Dr. Jia Niu of Boston College is developing a new class of sugar-based polymers called pseudo-polysaccharides. These materials are inspired by natural polysaccharides—like cellulose and starch—but will be made with modifications not naturally found to impart new functions using synthetic techniques that allow for greater control over their structure and properties. The project will focus on designing sugar-based building blocks that are affordable and easy to produce, and then assembling them into polymers with precise control over their size and functional groups. These new polymers could lead to more sustainable plastics and advanced materials for medicine. In addition to the scientific goals, the project will include an outreach program called “Polymers and You,” developed in partnership with Housing Families, a nonprofit organization in Malden, MA. This initiative will offer educational workshops and research opportunities to middle school-aged youth in the Greater Boston area, including those who are homeless, helping to inspire the next generation of scientists and engineers. This research will establish a synthetic platform for accessing precision pseudo-polysaccharides, an emerging class of polysaccharide-like polymers consisting of monosaccharide repeating units and non-native linkages in the backbone, through the design and polymerization of sugar-based monomers. The project will enhance our fundamental understanding of synthesizing polysaccharide-based polymers by exploring three distinct polymerization strategies. The first strategy is focused on the radical ring-opening and cascade polymerizations of cyclic ketene acetals and exomethylene-monosaccharides, as well as their copolymerization with vinyl monomers. The second strategy will leverage stereoselective cationic ring-opening polymerization of cyclic thionocarbonates and thionocarbamates to enable the synthesis of stereoregular thiocarbonate-linked pseudo-polysaccharides and their copolymers with vinyl monomers. The third strategy explores anionic polymerization of sugar-derived lactones to construct ester-linked pseudo-polysaccharides. Each approach will be used to investigate how sugar structure, protecting groups, and heteroatom incorporation influence monomer reactivity, polymer architecture, and stereoselectivity. The resulting polymers will feature well-defined molecular weights, narrow dispersities, and tunable chain-end functionalities. The insights gained from this work will not only enable the scalable and well-controlled synthesis of pseudo-polysaccharides but also provide generalizable principles for designing sustainable, recyclable, and functional polymeric materials. 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.