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Hydrophobic materials possess exceptional properties, making them extensively useful in daily production and life. However, developing low‐cost and flexible hydrophobic materials remains a challenging task. In this study, a series of composite emulsions were prepared by introducing hydroxyl‐terminated polydimethylsiloxane as a modifier into polyurethane acrylate via a solvent‐free approach. The composite emulsions were then used to fabricate polymer films using the solvent evaporation technique. The effects of varying siloxane content on the properties of composite emulsions and polymer membranes were examined. The results showed that increasing the siloxane content improved the hydrophobic properties and flexibility of the film materials. Fourier transform infrared spectroscopy confirmed the introduction of the SiOSi group into the polyurethane chain structure, the absorption peak for asymmetric stretching vibration of SiOSi is at 1100 cm−1. The mechanical properties test revealed that the film had excellent elongation at break (278.96 ± 0.01%), and a hydrophobic surface with a contact angle of 101.94° was obtained. The composite materials showed improved water resistance and thermal stability with the increase in siloxane content. The hydrophobic film is a promising material for application in decoration, architecture, and flexible wearable devices. [ABSTRACT FROM AUTHOR]

This work focuses on two meaningful points in green chemistry, one is providing a practical solution for CO2 transformation into a CO2 copolymer, and the other is disclosing the potential application of a CO2 copolymer as a water dispersible binder to overcome the bottleneck in heavy metal free anti-corrosion coatings. For the first point, a CO2-copolymer like CO2-polyol is synthesized from the telomerization of CO2 and propylene oxide using a zinc–cobalt double metal cyanide complex as a catalyst and terephthalic acid as a chain transfer agent. For the second point, for the past 30 years conducting polyaniline, with its unique anti-corrosion behaviour, has been regarded as a heavy metal free anti-corrosion material, but the development of a waterborne polyaniline anti-corrosion coating has encountered an impasse owing to the lack of a compatible binder. Therefore, a water borne cationic polyurethane dispersion (CPUD) was developed for this purpose, in which CO2-polyol was used as a soft segment, and 1,4-butanediol di(3-diethylamino-2-hydroxypropyl alcohol) ether was synthesized as a side-chain cationic extender. Unlike earlier acidic water borne dispersions, this water borne CPUD was near neutral, ensuring good compatibility with an aqueous conducting polyaniline dispersion, and is expected to create significant possibilities for the development of a novel generation of sustainable and eco-friendly metal anti-corrosion materials. [ABSTRACT FROM AUTHOR]

Currently, with the rapidly evolving technology landscape, there is growing demand for advanced secure information encryption and anti-counterfeiting technologies. Multi-stimulus-response materials have gained significant attention due to their promising application potential. In this study, 2,7-dichlorofluorescein (DCF) was anchored onto waterborne polyurethane chains to synthesize a fluorescent waterborne polyurethane (FWPU) with multi-stimulus response properties. The demulsification-induced fast solidification (DIFS) method developed by our group combined with the electrochemical approach was used to prepare an in situ information-encrypted coating on a metal surface. A triple-locked information-encrypted system based on anodic metal selection and pH-regulated fluorescence intensity was successfully designed and prepared. The anodic metal ions were automatically introduced in the process of preparing the FWPU coating, and the fluorescence intensity of FWPU was reduced or quenched by heavy metal anodes. Concurrently, the introduced DCF group in FWPU underwent structural change from a lactone ring to a quinone structure at higher pH levels, leading to a shift in fluorescence intensity. The pH response of FWPU coating and the change in fluorescence intensity with pH and anode metal were investigated by UV–vis and fluorescence spectra analysis. This innovative approach achieved multiple-stimulus response, enabling both encryption and decryption of information from one-dimensional to three-dimensional modes. The findings in this study may broaden the applications of information encryption, anti-counterfeiting, and fluorescent probes. • 2,7-Dichlorofluorescein was anchored to the main chain of fluorescent waterborne polyurethane by synthesis. • Fluorescent waterborne polyurethane has fluorescence pH response and Cu2+ quenching. • The FWPU coating with strong information encryption ability was prepared by demulsification-induced fast solidification. • The introduction of metal ions increases the fluorescence switch. [ABSTRACT FROM AUTHOR]