Oleogel Microsphere‐Based Composite Protective Coatings with Room‐Temperature Self‐Healing Enabled by a “Soft + Hard” Hybrid Architecture

Abstract

AbstractIntrinsically self‐healing coatings are compelling candidates for highly reliable anti‐corrosion technologies because of their easy implementation, low cost, and repeatable self‐healing. However, most of these coatings require intervention to initiate healing due to the locking of their chain segments under ambient conditions (to provide sufficient mechanical strength). Herein, a “soft + hard” hybrid architecture strategy of preparing oleogel‐based protective coatings with room‐temperature and repeatable self‐healing is proposed by embedding “soft” self‐healing and viscoelastic oleogel microspheres (OMs) in “hard” waterborne epoxy matrix. Such a decoupled design affords both instantaneous healing without external stimuli (crack narrowing within 10 min and protection recovered within 5 h) and good mechanical properties (improved wear resistance with an 80% reduction in friction coefficient, a 63% reduction in wear volume, as well as a maintained adhesion strength of 96%). The slippery and hydrophobic OMs also bring anti‐biofouling, interfacial water repellency, and inhibitor loading‐release features, leading to coatings with superior corrosion protection (>1010 Ω cm2 impedance modulus throughout 110 d) rather than just their self‐healing. This work demonstrates a feasible approach to integrating room‐temperature repeatable self‐healing and sufficient mechanical strength in future coating design.