Microcapsule‐Mediated Vibration‐Induced Emission for Real‐Time Visualization of Polymer Deformation

Abstract Mechanochromic materials usually exhibit observable changes in photophysical properties under force stimulation, and have attracted increasing attention due to their wide range of potential applications. Herein, the study designs and synthesizes mechanochromic microcapsules that harness mechanically triggered release to precisely modulate the excited‐state conformation of vibration‐induced emission (VIE) fluorophores. Double‐shelled polyurethane/poly(urea‐formaldehyde) microcapsules encapsulating hexyl‐acetate solution of VIE molecules are fabricated via in situ emulsification condensation polymerization. The microcapsules can protect VIE molecules from external environmental interference and be embedded with various polymers without chemical modification to build mechanochromic materials. Mechanical activation triggers instantaneous rupture of the microcapsules; the vibrational limitation of VIE molecules due to solvent evaporation provides detectable fluorescent color changes, making it possible to monitor polymer damage and deformation through naked‐eye vision. This microcapsule‐based mechanochromic material exhibited exceptional sensing performance under complex external forces, offering new mechanistic insights for the design of intelligent mechanoresponsive systems.