Near-Infrared Responsive Smart Superhydrophobic Coating with Self-Healing and Robustness Enhanced by Disulfide-Bonded Polyurethane

Abstract

Synergistic self-healing materials and inorganic particles to create self-healing superhydrophobic surfaces for improving their robustness is a common technique, but the suitability between the two is rarely mentioned. In this work, we developed a multifunctional superhydrophobic coating with room-temperature stability, mechanical stability, self-healing, and NIR stimuli response, in which self-healing polyurethane (PU) serves as the interface reinforcement layer and poly­(dopamine) (PDA)-coated flower-like ZnO composite particles serve as the hydrophobic layer. A series of temperature-dependent self-healing PU materials were designed and synthesized by regulating the ratio of hard and soft chain segments in PU, and the relationship between the healing temperature of PU and the hydrophobic stability of the composite coatings was investigated. Based on dynamic hydrogen and disulfide bonds, PUs displayed excellent self-healing performance. Thanks to the self-healing and interfacial strengthening effect of PU and the photothermal properties of PDA, the composite coating exhibits not only excellent mechanical stability but also rapid self-healing ability in response to NIR stimuli. Furthermore, the smart coating demonstrated superior self-cleaning and corrosion resistance. This work provides a reference for developing strong and stable water-repellent reversible superhydrophobic coatings with great potential and promising future.

Self-Healing, Robust, Liquid-Repellent Coatings Exploiting the Donor–Acceptor Self-Assembly

“…(d) Comparison of the self-healing properties of DA-PU with different repair mechanisms. (Previous work on D–A self-assembly, Diels–Alder chemistry, , disulphide linkage, − phenolic urethane chemistry, microcapsule, segmented PU, and multiple hydrogen bonding. − Details are presented in Table S1 in the Supporting Information).…”

Self-Healing of Biocompatible Superhydrophobic Coatings: The Interplay of the Size and Loading of Particles

“…After degradation via exposure to oxygen plasma, the coating is able to recover superhydrophobicity spontaneously within 20 min. Li et al fabricated a near-IR light-responsive self-healing superhydrophobic coating using polyurethane and polydopamine-modified ZnO NPs . The scratch-degraded coating can regain superhydrophobicity after either heating at 70 °C for 1 h or 30 s exposure to near-IR laser light.…”

“…Li et al fabricated a near-IR light-responsive self-healing superhydrophobic coating using polyurethane and polydopaminemodified ZnO NPs. 28 The scratch-degraded coating can regain superhydrophobicity after either heating at 70 °C for 1 h or 30 s exposure to near-IR laser light. A more ecofriendly approach was demonstrated recently by Sun et al where natural diatom and beeswax were used to prepare a self-healing superhydrophobic coating.…”

Molecular Engineering of Binder for Improving the Mechanical Properties and Recyclability of Energetic Composites

“…The zigzag arrangement of hydrogen bonds can destroy the regularity of polymer chains and promote the exchange of hydrogen bonds [ 21 ]. On the other hand, the disulfide bond as a weak dynamic covalent bond could be reformed and exchanged at a suitable temperature [ 22 , 23 ], thus endowing materials with self-healing [ 24 , 25 ] and reprocessing properties [ 26 ]. In addition, the dynamic exchange of disulfide bonds is conducive to the reorganization of entangled polymer chains [ 27 ], further improving the toughness of materials [ 28 ].…”