In this EAGER project funded by the Macromolecular, Supramolecular and Nanochemistry Program of the Chemistry Division, Rigoberto Advincula of the University of Houston will study how to synthesize polymers with their backbones twisted into precisely-defined knots. The approach is to synthesize supramolecular metal complexes in which the ligands are linked together into knots via chains that contain iniferters for reversible addition-fragmentation chain transfer (RAFT) polymerizations or ring insertion polymerizations (RIP). Next, the links will be expanded via polymerization, and finally the metal ion templates will be removed to yield the free, knotted polymer. The broader impacts involve training undergraduate students and graduate students, incorporating template synthesis and knot theory into the chemistry curriculum at the university, and creating a website describing the results of the project and containing educational information on knot theory.
This work will enhance our fundamental understanding about the physical behavior of polymer chains. Polymer chains are the fundamental units of plastic materials, and further knowledge about their properties could lead to new applications in adhesives, structural materials, and automotive and aerospace composites.