In this work, we report a dynamic mechanophore system enabled by Cu-catalyzed ring-opening condensation polymerization of propargyl cyclic carbonates, featuring a diyne backbone with mechanosensitive propargylic/benzyl C(sp3)-C(sp3) linkages and simultaneously unmasked hydroxy side chains. The weak C–C linkages generate stabilized mechanoradicals under stress, which recombine at ambient temperature. Meanwhile, the hydroxy side groups facilitate the seamless incorporation of macromolecular cross-linkers in polyurethane (PU) networks, yielding elastomers with enhanced tensile strength, toughness, and self-healing efficiency. Molecular weight-dependent mechanosensitivity suggests potential topological effects. This work provides an approach to high-performance dynamic networks with a sensitive mechanochemical response.
