Self‐Healing Ionomers: Ionic Interactions, Mechanisms, and Emerging Applications

Self‐healing polymers have emerged as an important class of advanced materials capable of autonomously or stimuli‐responsively restoring mechanical integrity after damage. Among them, ionomers occupy a unique position due to the presence of reversible ionic interactions that simultaneously impart mechanical strength, toughness, and healing capability. This review provides a comprehensive and critical overview of self‐healing ionomers, focusing on the fundamental role of ionic interactions, the mechanisms governing damage repair, and recent advances in material design. The structure–property–healing relationships of ionomers are discussed in detail, with emphasis on ionic aggregates, counterion chemistry, and microphase separation. Various classes of self‐healing ionomers, including thermally activated, moisture‐assisted, and room‐temperature autonomous systems, are systematically reviewed. Representative material systems such as polyethylene‐, polyurethane‐, acrylic‐, styrenic‐, and bio‐based ionomers are highlighted. The influence of key parameters on healing efficiency, state‐of‐the‐art characterization techniques, emerging applications, sustainability aspects, and current challenges are critically analyzed. Finally, future research directions, including smart ionomers and AI‐guided polymer design, are outlined.