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[Display omitted] • The innovative application of the semi-IPN pressure-sensitive adhesive for transdermal drug delivery system. • Pressure-sensitive adhesive with excellent mechanical properties, effective adhesion to the skin, and high drug release. • A simple but effective method to synthesize the semi-IPN pressure-sensitive adhesive with high cohesion and adhesion. The application of pressure-sensitive adhesives (PSAs) in transdermal drug delivery systems (TDDSs) is limited. Insufficient cohesion in TDDS can lead to cold flow, patch displacement, dose inaccuracies, and the 'dark ring' phenomenon. To address these issues, we developed a semi-interpenetrating network (semi-IPN) PSA using a 2-hydroxyethylacrylate-modified acrylic copolymer as the linear polymer and poly[tri(propylene glycol) diacrylate] as the cross-linked network. Semi-IPN PSAs have better mechanical properties compared to traditional PSAs. The cohesion of the semi-IPN PSA was 31 times and 1.6 times that of commercially available DURO-TAK®87-2287 and DURO-TAK® 87–4098, respectively, and the cold flow of the semi-IPN PSA was significantly reduced. Furthermore, the semi-IPN PSA adhered to the human forearm for longer time and did not exhibit the 'dark ring' phenomenon after removal. When loaded with flurbiprofen, the semi-IPN PSA was found to maintain high levels of drug release and skin permeation amount, and flurbiprofen loading did not affect its superior cohesive performance. In conclusion, the innovative application of the semi-IPN PSA for TDDS showed excellent mechanical properties, effective adhesion to the skin without irritation, and highly effective drug release. These findings indicate that the use of the semi-IPN is both simple and highly effective for TDDS. [ABSTRACT FROM AUTHOR]

[Display omitted] • An acoustic metafluid made of hollow regular polygons immersed in water is proposed, which can realize independent manipulation of mass density and bulk modulus. • A theory model is established to accurately calculate the effective acoustic parameters of the proposed metafluid. • The underwater impedance-matched gradient index lens and carpet cloak have been designed and experimentally demonstrated based on the proposed metafluid. Tuning the mass density and bulk modulus independently is the key to manipulate the propagation of sound wave. Acoustic metamaterials provide a feasible method to realize various acoustic parameters. However, the relevant studies are mainly concentrated in air, and the huge impedance difference makes it difficult to directly extend these airborne structures to underwater application. Here, we propose a metafluid to realize independent manipulation of the mass density and bulk modulus underwater. The metafluid is composed of hollow regular polygons immersed in the water. By adjusting the side number of the hollow regular polygons and choosing proper materials, the effective mass density and bulk modulus of the metafluid could be modulated independently. Based on the flexible adjustment method, metafluids with same impedance but different sound velocities are designed and used to realize an underwater impedance-matched gradient index lens. In addition, by combining the proposed metafluid with other artificial structures, acoustic parameters with great anisotropy can be achieved, which is exemplified by the design and demonstration of an impedance-matched underwater acoustic carpet cloak. This work can expand the practicability of underwater metamaterials and pave the way for future potential engineering applications in the practical underwater devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Superhydrophobic ZnO@STA@PDMS coating was designed via spraying method. • The coating possesses fluorine-free, substrate-independent and robust properties. • EIS and polarization results present greatly enhanced corrosion resistance. • A new salt-deliquesce self-coalescence anti-corrosion mechanism was proposed. • The coating provides promising applications in marine submerged and atmospheric zones. Biomimetic superhydrophobicity endows various substrates with amazing multi-functional properties. However, fragile hierarchical structures, fluorine-containing chemicals usage, and strict requirements for substrate scopes remain thorny challenges. Herein, we constructed a mechanical robust superhydrophobic ZnO@STA@PDMS coating with fluorine-free reagents through wide-applicable and substrate-independent spray-coating method. Field-emission scanning electron microscopy (FE-SEM), energy-dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and contact angle meter were used to assess the surface micro-nano structures, chemical compositions, thermal stability and wettability variations. The corrosion resistance of the developed superhydrophobic ZnO@STA@PDMS coating was evaluated by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization measurements. The corrosion current density (I corr) of the substrate reduces by two orders of magnitude after being spray-coated with superhydrophobic ZnO@STA@PDMS coating, indicating excellent corrosion resistance in marine submerged zone. In simulated marine atmospheric conditions with high relative humidity, the salt-deliquesce behaviors of single and double NaCl particles on bare and coated Q235 carbon steel surfaces were recorded. In a high humidity atmospheric environment, the instantaneous salt-deliquesce self-coalescence phenomena provides a new type of anti-corrosion mechanism. Furthermore, the prepared superhydrophobic coating can withstand more than 30 tape-peeling cycles and 400 cm abrasion distance, demonstrating good mechanical stability in prospective real-world applications. [ABSTRACT FROM AUTHOR]