Dry adhesives that combine strong adhesion, high transparency, and reusability are needed to support developments in emerging fields such as medical electrodes and the bonding of electronic optical devices. However, achieving all of these features in a single material remains challenging. Herein, we propose a pressure-responsive polyurethane (PU) adhesive inspired by the octopus sucker. This adhesive not only showcases reversible adhesion to both solid materials and biological tissues but also exhibits robust stability and high transparency (>90%). As the adhesive strength of the PU adhesive corresponds to the application force, adhesion could be adjusted by the preloading force and/or pressure. The adhesive exhibits high static adhesion (∼120 kPa) and 180° peeling force (∼500 N/m), which is far stronger than those of most existing artificial dry adhesives. Moreover, the adhesion strength is effectively maintained even after 100 bonding–peeling cycles. Because the adhesive tape relies on the combination of negative pressure and intermolecular forces, it overcomes the underlying problems caused by glue residue like that left by traditional glue tapes after removal. In addition, the PU adhesive also shows wet-cleaning performance; the contaminated tape can recover 90–95% of the lost adhesion strength after being cleaned with water. The results show that an adhesive with a microstructure designed to increase the contribution of negative pressure can combine high reversible adhesion and long fatigue life.

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This study aims to evaluate the effects of different electrolyte concentrations on titanium-porcelain bonding strength after microarc oxidation (MAO) treatment. Four MgSiF6 electrolyte concentrations (10 g/L, 20 g/L, 30 g/L, and 40 g/L) were chosen for the MAO bath solutions. According to ISO 9693, the bonding strengths of titanium-porcelain restorations were detected by the three-point bending test. Scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) were applied to evaluate the morphologies and elemental compositions of the MAO coating, titanium-porcelain fracture surfaces, titanium-porcelain interfaces, and oxygen diffusion. The bonding strength of the 20 g/L MgSiF6 group was significantly higher than that of the control group. However, overly high MgSiF6 concentrations had a negative influence on the bonding strength between titanium and porcelain. The results demonstrate that MAO treatment with only appropriate electrolyte concentration can improve the titanium-porcelain bonding strength.

Photosensitive glass-ceramics have been extensively studied in recent years in that it is an attractive high diffraction efficiency grating materials. It is based on Stookey’s mixed fluoride sodium glass system for us to adopt, design prescriptions on the basis of SiO2-Na2O-Al2O3-ZnO for the glass main component and a series of glass doped with CeO2, AgNO3 and NaF etc. melted at about 1450 °C, and the glass have good optical property (homogeneity, without bubble and stripe, high transparency). The borosilicate glass was exposed by ultraviolet light, and then after the heat treatment of the sample, the measurement of ultraviolet-visible-near infrared absorption spectrum and the X ray diffraction of exposure part was performed.