In typical cyclic polymer synthesis via ring-closure, chain growth and cyclization events are competing with each other, thus affording cyclic polymers with uncontrolled molecular weight or ring size and high dispersity. Here we uncover a mechanism by which Lewis pair polymerization (LPP) operates on polar vinyl monomers that allows the control of where and when cyclization takes place, thereby achieving spatial and temporal control to afford precision cyclic vinyl polymers or block copolymers with predictable molecular weight and low dispersity (~1.03). A combined experimental and theoretical study demonstrates that cyclization occurs only after all monomers have been consumed (when) via conjugate addition of the propagating chain end to the specific site of the initiating chain end (where), allowing the cyclic polymer formation steps to be regulated and executed with precision in space and time.
Bibliographical noteKAUST Repository Item: Exported on 2022-02-11
Acknowledgements: We gratefully acknowledge support by the U.S. National Science Foundation (NSF-1904962) for the work by MLM and LTR, and the U.S. Army Research Office (W911NF1810435) for the work by RWC. We thank Dr. Roy Geiss for his expertise and assistance with acquiring TEM images.
ASJC Scopus subject areas
- General Chemistry