Strain-Driven Ring-Opening Metathesis Polymerization

Ring-opening metathesis polymerization (ROMP) has grown from an extension of olefin metathesis into a powerful, modular platform for synthesizing precision macromolecules. In this review, we explore the evolution and current landscape of strain-driven ROMP, beginning with historical and mechanistic foundations. A central focus is placed on the concept of ring strain─its theoretical basis, thermodynamic consequences, and practical implications for polymerizability. We critically examine the roles of Δ<i>H</i>, Δ<i>S</i>, and computational tools in guiding monomer selection and design, with tabulated comparisons across key monomer classes including cyclopropenes, cyclobutenes, cyclopentenes, larger rings, and bridged-ring systems. This review aims to bridge foundational understanding with new opportunities, guiding both experienced practitioners and newcomers in advancing the frontiers of ROMP.