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In this work, a simple anti‐fingerprint strategy (reduced ≈40–60%) to rearrange fingerprint droplets by patterned micro/nano‐pore/spoons texture, air cushion and low surface energy is reported. Superior to previous precise and complex preparation methods, the micro/nano‐texture are fabricated through conventional process of spray and dip. The pore and spoon can be freely switched by changing the process. The number (N) and size (r) of pores and spoons are controlled intelligently by solvent volatilization and interfacial tension (γFP/PU−H2O${{\bm{\gamma }}_{{\rm{FP/PU}}{\bm{ - }}{{\rm{H}}_2}{\rm{O}}}}$ and γFP/PU − Solvent), the key for pore/spoon's forming and expanding. A physical model of interface intelligent controlling the micro/nano‐pore/spoon surface texture induced by "Vacancy‐Capture" is proposed. The description is being reported, for the first time, to the knowledge, expecting to make it possible to prepare anti‐fingerprint engineering materials with newly potential industrial applications on optical device for large‐scale in the future. [ABSTRACT FROM AUTHOR]

Bionic self‐cleaning coatings have exhibited scaling inhibition for their low surface free energy. The key issue is focused on the long‐term anti‐scaling performance for the hydrophobicity failure after scaled. Inspired by "grass‐to‐stone" phenomenon, we reported a polymer coating (WCA = 120°, WSA = 14°) with the water contact angle of its 720 h‐scaled surface increased to 135°and scaling reduced by 90–95%. The nucleation and growth of CaCO3 at "coating‐crystal" interface are investigated, and a physical model for self‐healing film interface inhibiting scaling is innovatively proposed, as an important step toward designing long‐term anti‐scaling coating for engineering application. [ABSTRACT FROM AUTHOR]

In view of the technology bottleneck of the adhesion failure of traditional functional protective coatings on the smoother surface of precise parts served in the marine atmosphere, a room-temperature-curable fluoropolymer/polyurethane (denoted as RFP) polymer composite coating of 20–30 μm is prepared on the metal substrates. Static pull-off and dynamic friction test methods are used to evaluate the interface adhesion of the coating. The coating shows superior adhesive strength of 18–24 MPa on a variety of metal substrates with a wide range of surface roughness (Ra = 0.1–1.6 μm). The friction coefficient of the coating surface is about 0.05–0.08, and the wear life is up to 9–12 km/μm. Furthermore, the adhesion strength of the coating remains 12–14 MPa after 1600 h of salt spray while the wear life of the coating keeps 3–9 km/μm after 720 h of salt spray. The influences of surface roughness (R a) , surface free energy (γ O x i d e ), surface potential (φ O x i d e) of the metal substrates and the bonding force at substrate-coating interface on the adhesive energy (E a d h.) are discussed, and the mechanism of "physical-chemical-surface" synergetic enhanced interface adhesion is proposed. The RFP coating is used as the intermediate layer for traditional PU and EP coatings to improve their adhesion on smooth aluminum substrate from 1.39 MPa to 17.5 MPa (increased by 1260 %). Thus, the polymer coating has the potential to provide technical support for the development of long-term anticorrosive coating technology for precision components of marine high-tech equipment. • The RFP polymer coating showed adhesive strength of 18-24 MPa on metals with surface roughness (Ra) about 0.1-1.6 μm. • Static pull-off and dynamic friction tests were integrated to evaluate the interface adhesion and reveal its mechanism. • The adhesion remained 12-14 MPa after 1600 h of salt spray and the wear life reached 3-9 km/μm after 720 h of salt spray. • Ra , γ O x i d e , φ O x i d e E a d h. .A mechanism of "physical-chemical-surface" synergetic enhanced interface adhesion has been innovatively proposed. • The RFP coating shows promise in addressing adhesion for functional coatings on smoother substrates or primers. [ABSTRACT FROM AUTHOR]

At present, mechanical de-rust technologies (grinding and sandblasting) are forbidden in some specific engineering fields such as oil drilling platforms equipped with storage tanks, chemical pipelines and power transmission system. It is passivated rust with cracks and holes that is known to hinder adhesion between anticorrosive coating and metallic substrate. This paper reported an organic-organic fluoropolymer/polyurethane (PF/PU) polymer coating, showing strong adhesion strength of 18.2 MPa with rust and 16.5 MPa after 240 h salt spray test, which is 2–3 times higher than conventional inorganic-organic epoxy (EP) coating (6–9 MPa). The PF/PU coating have protected rusted chemical pipelines from marine atmosphere corrosion for 3 years. Due to the micro/nano-channels in the rust layer, PF/PU precursor of appropriate surface tension and viscosity spontaneously adsorb/adhesive, wet, spread and fill with the channel by capillary force. A composite polymer-rust‑iron substrate with three-dimensional interpenetrating network is fabricated via mechanical interlocking/chemical bonding and PU cross-linking. The physical model of "capillary filling of polymer coating in micro/nano-rust-channels (μ/nRCs)" is proposed and demonstrated by "spinning by air cushion escaping" phenomenon as one end of the channel sealed. Based on researches and practical engineering applications on chemical pipelines and subway/railway tracks, a new polymer coating technology with rust towards on-site maintenance has been developed, aiming to realize the surface function remanufacturing of high-tech equipment served in severe corrosive medium and improve reliability of the equipment. [Display omitted] • A PF/PU polymer coating was designed to fabricate a polymer-rust‑iron with three-dimensional interpenetrating network. • The PF/PU coating with rust showed strong adhesion strength of 18.2 MPa, even 16.5 MPa after exposed to salt spray for 240 h. • A physical model of "capillary filling of polymer coating in micro/nano-rust-channels (μ/nRCs)" is proposed. • "Spinning by air cushion escaping" phenomenon is found at the rust-coating interface with the channel outlets sealed. • Based on engineering applications, a new polymer-coating-technology with rust towards on-site maintenance has been developed. [ABSTRACT FROM AUTHOR]

Surface behaviors of superhydrophobic polymer coating applied in severe engineering environment are firstly systematically investigated. The PTFE/PPS (Polytetrafluoroethylene/Polyphenylene sulfide) coating still possess good superhydrophobicity after natural ice and snow covering for 10 day due to its micrometer-nanometer-scale binary structure (MNBS) with long-term stability. Scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) and water contact angle (WCA) are used to characterize the morphology, chemical components and wetting properties of the coating, respectively. Surprisingly, the PTFE nano-fibers on most micro-scale papillae of the original coating were 'chemical-etched' and then 'secondary-constructed' to form nano-spheres/papules by HSO under 'accelerated simulated acid rain' condition (pH = 0.3). It is firstly found that chemical-etching by simulated acid rain only result in the 'secondary-construction' of MNBS structure. However, the laboratory weathering tests indicated that light-etching by the light with specified wavelength (UV, about 300-400 nm) can lead to both the 'secondary-construction' of MNBS structure and the change of surface chemical composition/groups on the superhydrophobic coatings. This thesis clarifies the long-term stability and surface behaviors of the superhydrophobic polymer coating under severe engineering condition, and will provide significant theoretical guidance for superhydrophobic polymer coating as anti-ice/frost engineering material. [ABSTRACT FROM AUTHOR]