CAREER: Ribosome-inspired Synthesis of Precision Polymers

Purdue University, West Lafayette IN

Investigators

Abstract

Nature builds very large molecules (so called polymers) with molecular assembly lines. Crucial for life, these assembly lines add building blocks to growing polymer chains one after another in a specific order. This is how DNA and RNA are formed. In this project, Dr. Schneebeli is imitating the natural assembly-line approach to create well-defined polymeric materials. While this research focuses on enabling and understanding artificial molecular assembly lines, the well-defined polymers created may ultimately be useful materials for a variety of important applications. The artificial molecular assembly lines are created by connecting a catalyst to the polymers with rings that slide along the growing chains. This catalyst adds individual building blocks to the growing polymers one by one. In addition, Dr. Schneebeli is engaging the public in polymer chemistry through K-12 outreach at a local science museum (ECHO Lake Aquarium and Science Center in Burlington, VT) and at local high schools. For this outreach, Dr. Schneebeli is inventing interactive dynamic models. These models lead K-12 students to discover key aspects of polymer growth independently and foster independent creative thinking within the future STEM workforce. With support from the Chemical Catalysis Program of the Chemistry Division, Dr. Schneebeli of the University of Vermont is learning how to enable new polymerization mechanisms that could ultimately result in molecular assembly lines for sequence-defined, pi-conjugated polymers. Inspired by how Nature creates sequence-defined, functional macromolecules, Dr. Schneebeli is creating special interlocked catalysts, which can transform difficult-to-control step polymerizations into robust living chain-growth processes. While efficient chain-growth processes exist for numerous conjugated, cyclic, and hyperbranching monomers, this research explores a universal chain-growth strategy for general monomers, many of which cannot yet be polymerized in a controlled manner. Dr. Schneebeli's design prevents the catalysts from falling off the polymers, thus rendering this new living polymerization methodology fully chain-transfer free. Dr. Schneebeli is utilizing this new polymerization technique to enable the enzyme-free translation of DNA templates into diverse, pi-conjugated precision polymers, in a manner analogous to how the ribosome builds proteins. In support of the broader impacts of the project, Dr. Schneebeli is actively engaged in K-12 outreach with special macroscopic dynamic models. These models are devised to lead K-12 students to discover qualitative and quantitative aspects of different polymerization mechanisms to foster discovery-based reasoning and creative thinking among the future STEM workforce. 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.