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Luminescent oxygen sensor composed of platinum-porphyrin and a gas-permeable polymer binder was applied as an optical crack sensor paint for infrastructure. The sensor paints were designed as a three-layered structure in which the luminescent oxygen sensor layer was sandwiched between oxygen barrier layers. The sensor paints emitted intense luminescence under UV light irradiation, and the luminescence was efficiently quenched when a new crack formed on the concrete surface. Microcracks, which were

In this study, dual luminescent polymer sensors based on a pressure-sensitive palladium(II) tetraphenylporphyrin, PdTPP, and a temperature-sensitive europium(III) complex, EuDT, were newly fabricated by spray-coating or electrospinning of the solutions containing polystyrene as a matrix for the simultaneous detection of both pressure and temperature. The pressure and temperature responses were recorded as a function of the luminescence changes, and their sensitivities were carefully evaluated. The electrospun nanofibrous films exhibited a higher pressure-sensitivity than the corresponding spray-coated films, which was most likely attributed to their highly porous structures. In addition, accurate temperatures at the sample surface were determined from the luminescence intensities of the temperature-sensitive dye, which were used for the temperature correction of the surface pressure measurements. It was demonstrated that the accuracy of the pressure measurements based on the luminescence intensities of the pressure-sensitive dye was significantly improved after the temperature corrections. This is the first report of dual luminescent nanofibrous polymer sensors.

We have been developing smart photonic coating for structural materials to visualize strain mapping on steel or aluminum and to detect cracks on concrete. In the technology, strain imaging sheet made of colloidal photonic crystal film coated on a polyethylene terephthalate sheet. The strain imaging sheets change structural color by mechanical deformation. Now we have been testing smart photonic coating for real concreate bridges One of the key issues is the durability of the sheet for long-term use at the outfield site. In outdoor exposure test and in laboratory accelerated exposure test, polystyrene particles in the colloidal photonic crystal film were damaged and lost the structural color. To protect the deteriorating, top coat layer containing ultraviolet absorber was effective to reduce the damage of the colloidal photonic crystal film.

Here we will propose the conceptual new idea of the inspection of concrete bridge using smart materials and mobile IoT system. We apply opal photonic crystal film to detect cracks on concrete infrastructures. High quality opal photonic crystal films were coated on black color PET sheet over 1000 cm2 area. The opal film sheet was cut and adhered to concrete or mortar test pieces by epoxy resin. In the tensile test, the structural color of the opal sheet was changed when the crack was formed. As a demonstration, we have installated the opal film sheet on the wall of the concrete bridge. Our final purpose is the color change will be recorded by portable CCD devices, and send to expert via IoT network.

The paper reviews control of surface wetting via the production of polymer coatings sensitive to changes in external conditions. Graft polymer compositions having the adaptive properties are obtained by method of surface-initiated atom transfer radical polymerization on aluminum surface. The chemical composition of polymer coatings is confirmed by X-ray photoelectron spectroscopy. The morphology of the modified surface is investigated by scanning electron microscopy. The possibility of wetting control of modified aluminum surfaces modified in a wide range with a change in the pH value and temperature is shown.

Active control of flow over object surfaces achieved by means of mechanical and/or electrical methods has recently been studied. However, there has been no report on actively switching the surface drag of an object by chemical modification of the object's surface. Poly(N-isopropylacrylamide) (PNIPA) was grafted onto the surface of an aluminium (Al) substrate via (A) surface-initiated atom transfer radical polymerization and (B) radical polymerization with an azo-group surface initiator. The grafting density was 0.19 and 0.15 chains nm−2, respectively. The water contact angle of the PNIPA-grafted Al surface reversibly changed between 55° and 82° for (A) and between 42° and 65° for (B) at temperatures of 25 and 40 °C, which was ascribed to the temperature-responsive, hydrophilic–hydrophobic switching of the grafted PNIPA surface. The PNIPA grafting was applied on the surface of an ogive-shaped Al model. The normalized dropping speed of the model in water increased 1.1 times at 42 °C in comparison to that at 22 °C. Switching of the surface drag of PNIPA-grafted Al in water was demonstrated on the basis of the hydrophilicity and hydrophobicity of the grafted Al surface, the switching occurring with a change in temperature. Copyright © 2010 Society of Chemical Industry

A triple-layered luminescent polymer coating was prepared to simultaneously detect both oxygen and temperature upon the coating. The coating was composed of an oxygen and a temperature sensory layer based on platinumporphyrin (PtTFP) and ruthenium phenanthroline (Ru(phen)) dye molecule, respectively. The temperature-sensitive Ru(phen) was dispersed in gas-barrier polyvinyl alcohol as the first layer, which was further coated with a water-proofing fluorine-containing polymer. The oxygen sensory layer composed of the oxygen-sensitive PtTFP and high oxygen-permeative poly(1-trimethylsilyl-1-propyne) was coated as the third layer. The two luminescences were separately monitored: the oxygen partial pressure and temperature in the range of 0-21 kPa and of 25-120 °C were successfully detected.

Poly[1-trimethylsilyl-1-propyne-co-1-(3-pyridyl)propyne] 1 was prepared both as a polymer-ligand of a palladium porphyrin (PdOEP) and of a platinum porphyrin (PtTFP) and as a highly gas-permeable polymer matrix of the porphyrin. The porphyrin acted as a phosphorescence probe which could be quenched with oxygen and sense the oxygen partial pressure. 1 gave a smooth and tough coating with a thickness of ca. 2 µm which homogeneously involved the porphyrin. The porphyrin-1 coatings displayed strong red-colored phosphorescences (the emission maximum at 670 and 650 nm for PdOEP and PtTFP, respectively), and their intensity significantly decreased with an increase in the oxygen partial pressure on the coating. The high oxygen-quenching efficiency or the high oxygen pressure sensitivity of the porphyrin's phosphorescence was observed even at cryogenic temperature. Aggregation of the porphyrin was suppressed in the coating by ligation of the porphyrin with the nitrogenous residue of 1 to significantly reduce spatial noise in the phosphorescence measurement or the oxygen-pressure sensing. PtTFP-1 was coated on the surface of a delta wing model. The oxygen-pressure distribution on the coated model was successfully visualized in a cryogenic wind tunnel test. Copyright © 2008 John Wiley & Sons, Ltd.

We will present a simple and low cost method to visualize local strain distribution in deformed aluminum plates. In this study, aluminum plates were coated with opal photonic crystal film with tunable structural color. The photonic crystal films consist of a silicone elastomer that contains an array of submicron polystyrene colloidal particles. When the aluminum sheets were stretched, the change in the spacing of the colloidal particles in the opal film alters the color of the film. This approach could be useful as a new strain gauge having a visual indicator to detect mechanical deformation.

Start-up and shut-down cycling in PECFs causes severe degradation, because the carbon supports at the cathode catalyst layers are corroded due to the instantaneous reaction with H2O. We developed a new CO2 visualization system using a CO2-sensitive dye for detecting the generation of CO2 during the corrosion processes in real time and with spatial resolution. The corrosion occurring during the shut-down process continued longer near the inlet and produced a more serious effect than during the start-up process, near the outlet. This new CO2 visualization technique should help to minimize the corrosion of carbon supports in all types of PEFCs. © 2012 The Electrochemical Society. [DOI: 10.1149/2.018204esl] All rights reserved.

We describe the capsulation of colloidally templated polythiophene (P3-TAA) arrays with multi-walled carbon nanotubes (MWNTs) after colloidal template electropolymerization. The dissolution of the polystyrene (PS) particle templates, which were assembled via the Langmuir-Blodgett (LB)-like technique, allowed the formation of hollow-shell Janus type arrays.

Electrochemically oxidized patterns of stable poly(nitroxide radical)s at the nano-scale were demonstrated by controlling lithographic parameters, such as voltage, scan speed, and sweep duration.

A luminescent porphyrin dye film has been coated onto a transparent separator on the cathode side of a direct methanol fuel cell (DMFC) to visualise clearly oxygen distribution under operating conditions by analysing emission from the dye.