Ring-opening metathesis polymerization with 2–5 orders of rate increment

Abstract

The tuning of catalytic behavior in polymerization reactions using an organometallic catalyst has been achieved primarily by the design of new catalysts. In this work, however, ring-opening metathesis polymerization (ROMP) was tuned by an additional acid–base reaction without synthesizing any new catalyst. The reaction rate of the ROMP was enhanced by 2–5 orders of magnitude with the help of an additional acid–base reaction. The use of various acids including hydrochloric acid, sulfuric acid, and boron trifluoride could effectively block the re-coordination of the pyridine ligand to promote the rate of polymerization significantly. The modified pathway allows for: (1) the polymerization of challenging monomers with high steric hindrance that can be hardly polymerized otherwise and (2) the polymerization of regular monomers under challenging conditions such as low temperature. Polymerization catalyzed by an additional reaction provides broad opportunities for polyolefin synthesis via ROMP and brings insights into the design of new catalytic systems without synthesizing new catalysts.