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The versatile absorption and fluorescence properties alongside the outstanding chemical and photostability make the rylene‐based derivatives one of the most investigated compounds in the field of third‐generation solar cells. Over the last 25 years, an intensive research activity has made the rylene‐based derivatives one of the most interesting and modular class of sensitizers in the dye‐sensitized solar cells. This critical analysis compares and discusses the state of the art of the rylene‐based dyes, starting from the pioneering studies on the perylene bisimides to the latest N‐annulated rylene derivatives. The focus of this review is to discuss the structure‐to‐properties relationship highlighting how critical points have been overcome and what are the most recent approaches toward the achievement of novel record efficiencies in the dye‐sensitized solar cells. [ABSTRACT FROM AUTHOR]

Polyvinyl butyral (PVB) is a high-performance thermoplastic polymer, commonly used as an interlayer material in laminated safety glass for the automotive and architectural sectors. Currently, there is no end-of-life cycle program for a substantial amount of PVB film, which mainly ends up in landfills. According to a circular approach, PVB can be revalorized after efficient separation and recovery from glass. Thus, the aim of this work was to develop functional coatings for textile applications using recycled PVB (re-PVB), also in combination with an organic UV absorber, to enable the production of UV-protective final coated fabrics. The re-PVB-coated fabrics were obtained through an industrially scalable spraying process (leading to an average weight increase of 20 ± 3 wt.%), and the effectiveness of the application was evaluated according to different characterization techniques, such as FT-IR (Fourier transform–infrared) spectroscopy, SEM (scanning electron microscope), a washing test, a mechanical test, a thermo-physiological test, and the ultraviolet protection factor (UPF). Based on the results, the re-PVB-coated fabrics appeared stable upon washing (with a negligible weight loss compared to the average amount of coating) and effective in UV protection (with a final UPF being four times higher and a reduced UVA transmittance from 2.0% to 0.6%). [ABSTRACT FROM AUTHOR]

In this study, the protic ionic liquid N,N-diethyl-3-sulfopropan-1-ammonium hydrogen methanedisulfonate is synthesized and characterized with the aim of elucidating its transport properties. A unique feature of this ionic liquid are the exchangeable acidic protons present on the anion and the cation, both of which contain low proton affinity sulfonic groups. The pronounced superionicity of this liquid, highlighted in the Walden-plot (ΔW > 0.8), indicates the decoupling of the conductivity from ionic diffusion. To explicate this enhanced proton mobility, the diffusion coefficients of the protons were measured by Pulsed-Field Gradient Spin-Echo NMR experiments at different temperatures. Below 373 K the diffusion coefficients of the cationic and anionic exchangeable protons are comparable with the ones of the other protons of the respective ions, indicating a vehicular transport mechanism. However, in the temperature range 383–413 K the diffusion coefficient of one of the exchangeable protons exceeds the diffusion of both ions by an unprecedented factor between 2 and 3. This temperature-induced switch in the proton transport mechanism is the result of a mixed-ion proton-transfer chain, as also supported by computational simulations. Both experimental and theoretical findings suggest the existence of a Grotthuss(-like) proton transport mechanism at high temperature in this system. [ABSTRACT FROM AUTHOR]

Until recently, recycling thermoset polyurethanes (PUs) was limited to degrading methods. The development of covalent adaptable networks (CANs), to which PUs can be assigned, has opened novel possibilities for actual recycling. Most efforts in this area have been directed toward inventing new materials that can benefit from CAN theory; presently, little or nothing has been applied to industrially producible materials. In this study, both an industrially available polyol (Sovermol780®) and isocyanate (Tolonate X FLO 100®) with percentages of bioderived components were employed, resulting in a potentially scalable and industrially producible material. The resultant network could be reworked up to three times, maintaining the crosslinked structure without significantly changing the thermal properties. Improvements in mechanical parameters were observed when comparing the pristine material to the material exposed to three rework processes, with gains of roughly 50% in elongation at break and 20% in tensile strength despite a 25% decrease in Young's modulus and crosslink density. Thus, it was demonstrated that theory may be profitably applied even to materials that are not designed including additional bonds but instead rely just on the dynamic urethane bond that is naturally present in the network. [ABSTRACT FROM AUTHOR]

Polyvinyl butyral (PVB) is widely used as an interlayer material in laminated glass applications, mainly in the automotive industry, but also for construction and photovoltaic applications. Post-consumed laminated glass is a waste that is mainly landfilled; nevertheless, it can be revalorized upon efficient separation and removal of adhered glass. PVB interlayers in laminated glass are always plasticized with a significant fraction in the 20–40% w/w range of plasticizer, and they are protected from the environment by two sheets of glass. In this work, the aim is to develop a thorough characterization strategy for PVB films. Neat reference PVB grades intended for interlayer use are compared with properly processed (delaminated) post-consumed PVB grades from the automotive and construction sectors. Methods are developed to open opportunities for recycling and reuse of the latter. The plasticizer content and chemical nature are determined by applying well-known analytical techniques, namely, FT-IR, TGA, NMR. The issue of potential aging during the life cycle of the original laminated material is also addressed through NMR. Based on the findings, a sensor capable of directly sorting PVB post-consumer materials will be developed and calibrated at a later stage. [ABSTRACT FROM AUTHOR]