This National Science Foundation (NSF) grant will support research to understand the role of exchangeable covalent bonds on block copolymer and network self-assembly. The co-principal investigators, Christopher Evans and Charles Sing (ChBE), started research in September and will support two students working on both experiments and theory.

Block copolymers are useful in many applications such as epoxies, battery electrolytes, and nanolithography, and are valued for their ability to combine two functions into one material. The differing chemical monomers causes the blocks of the polymer to separate, like oil and water. However, because they are bonded together, the separation is limited to nanoscale domains consisting of one block or the other. Forming a regular, ordered pattern of these small domains is challenging as the ordered phases often exhibit defects, or deviations from the pattern, where the polymer chains become trapped.

The investigators propose to introduce dynamic links between blocks that will allow some of the block copolymers to exchange their sections with a nearby block copolymer. The investigators hypothesize that this additional freedom will give the system as a whole greater flexibility to achieve long-range order of the different phases. This faster assembly is expected to reduce processing time, energy, and waste. Evans and Sing plan to incorporate lessons about dynamic polymer characterization and molecular simulation into day-camp projects by partnering with the Girls Learning About Materials and the CURIE organizations.