At present, numerous methods have been developed to prolong the durability of superamphiphobic coatings. These studies mainly focus on the repairing of coating surface morphology and the supplement of low surface energy materials. These self-healing methods are performed on the surface of the coatings, which will not be self-healed when deep damage occurs. To provide a viable strategy to self-heal deep damaged coatings such as tearing and sharp cutting, a series of UV light curable self-healing superamphiphobic coatings were fabricated by deposition of hydrophobically modified and functionalized Al2O3 nanoparticles (SMANP) on the surface of UV light curable polyurethane acrylic resin containing disulfide bond (DSPUA) and subsequent UV light irradiation. The resultant coating can repel both water and oil and performs excellent superamphiphobicity. With the help of the disulfide exchange reaction, the coatings perform excellent self-healing behavior after sharp cutting; the scratches gradually disappear, and the surface recovers to an integrated one. Meanwhile, the coatings can also restore their superamphiphobicity after heating or UV irradiation. Moreover, the effects of temperature, disulfide bond contents, and UV light irradiation on the self-healing performance of coatings were studied in detail. It has been demonstrated that increasing temperature or disulfide bond content can improve the self-healing performance of coatings; meanwhile, UV light irradiation can dramatically improve the self-healing rate. The current findings not only unlock more possibilities of fabricating self-healing superamphiphobic coating but also provide preliminary understanding of the self-healing kinetics based on disulfide exchange reaction.

A series of novel polyelectrolyte-amphiphilie complexes were prepared by ionic self-assembly of cationic linear poly(ferrocenylsilane) (PFS) of [Fe(η-C 5 H 4 ) 2 SiMe(OCH 2 CH 2 NMe 3 I)] n (PFS) with anionic dendrons of 3,4,5-tris(n-alkan-1-yloxy)benzoic acid [(3,4,5)nG1-COOK, n ) 12, 14, 16, where n was the number of carbon atoms in the alkyl tail]. These complexes PFS-(3,4,5)nG1 (n ) 12, 14, 16) were characterized with XRD, FTIR, TG, DSC, cyclic voltammetry (CV), and polarized optical microscope (POM). XRD profiles indicated the presence of the crystalline phase in the complexes resulted from the dendritic amphiphiles, which formed the end-to-end bilayer lamellar structure with the long period d ) 4.84, 5.34, and 5.76 nm for n ) 12, 14, and 16, respectively. With increasing the length of amphiphile alkyl tails, the stacking order was improved. The ionic thermotropic liquid crystalline state was obtained from these PFS-(3,4,5)nG1 complexes at temperature above the melting point of the dendron crystal. CV measurements indicated that these PFS-(3,4,5)nG1 complexes exhibited a good reversible redox process. Our work provides for the first time a simply and facile approach to fabricate redoxactive PFS polymers with ionic thermotropic liquid crystalline phase by the ionic self-assembly.

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Two novel photoreversible poly(ferrocenylsilanes) (PFS) with coumarin side groups, i.e., halfand whole-substituted poly(ferrocenyl(3-(7-hydroxycoumarin) propyl)methylsilane), are synthesized by transition metal-catalyzed ring-opening polymerization of ferrocenyl(3-chloropropyl) methylsilane monomer and subsequent group exchange and nucleophilic substitution reaction. The two polymers are characterized by elemental analysis, 1 H and 13 C NMR, FTIR, UV-vis, emission spectra, TG, and DSC. Their photochemical reactivity and electrochemical behavior are studied by UV-vis spectra and cyclic voltammetry, respectively. The two PFS polymers, like coumarin derivatives, can undergo reversible photodimerization and photoscission, but the content of coumarin significantly affects their photochemical reactivity and electrochemical properties. The photochemical reaction of coumarin side groups can cause a reversible change of electrochemical behavior of these PFS polymers, i.e., the peak separation ∆E increases with photodimerization and decreases with photoscission again. Cyclic voltammograms indicate that the electrode processes of the films of both original and photo-cross-linked polymers coated on a glassy carbon electrode are diffusion controlled and quasireversible in a wide scan rate range in 0.1 M NaCl aqueous solution at room temperature because of a low rate of mass diffusion and slow rate of the change transfer between the active sites, judged from small kinetic parameters such as surface transfer coefficient Rn R , standard rate constant K s , and apparent diffusion coefficient D app of the electroactive species. Interestingly, the electrode process of the half-/whole-substituted PFS polymer was less reversible than the half-substituted one at high scan rate. Photoirradiation causes the electrode processes of the two coumarin PFS polymers to become less reversible due to the cross-linking of the films. These coumarin PFS polymers may have potential use in many fields because they combine the useful photochemical reactivity with redox activity.

A novel poly(ferrocenylsilane) with a coumarin side group was synthesized. This photoreversible polymer exhibits interesting electrochemical activities, which change with photodimerization and photoscission reactions of the coumarin moieties.