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The modular synthesis of biomass-based diols (BDOs) in a facile and general way remains a grand challenge. To surmount this hurdle, here we present a new synthetic route, namely employing a Passerini reaction followed by a thiol–ene click reaction, to prepare BDOs. By selecting readily available starting biobased materials, including acids, aldehydes, isonitriles, and hydroxythiol as the building blocks, this method offers a convenient and efficient way for accessing structurally diverse BDOs without the need for catalysts and under mild reaction conditions. Specifically, the ability of our method to precisely regulate BDOs' aliphatic pendant chain length is demonstrated, which facilitates the development of waterborne polyurethane films with exceptional waterproof performance. By simplifying the BDO synthesis process, this method is poised to lead to a prosperous development for BDOs. [ABSTRACT FROM AUTHOR]

The gut is the body's largest immune organ, and the intestinal barrier prevents harmful substances such as bacteria and toxins from passing through the gastrointestinal mucosa. Intestinal barrier dysfunction is closely associated with various diseases. However, there are currently no FDA-approved therapies targeting the intestinal epithelial barriers. Long noncoding RNAs (lncRNAs), a class of RNA transcripts with a length of more than 200 nucleotides and no coding capacity, are essential for the development and regulation of a variety of biological processes and diseases. lncRNAs are involved in the intestinal barrier function and homeostasis maintenance. This article reviews the emerging role of lncRNAs in the intestinal barrier and highlights the potential applications of lncRNAs in the treatment of various intestinal diseases by reviewing the literature on cells, animal models, and clinical patients. The aim is to explore potential lncRNAs involved in the intestinal barrier and provide new ideas for the diagnosis and treatment of intestinal barrier damage-associated diseases in the clinical setting. [ABSTRACT FROM AUTHOR]

A large size, sensitive response thermally expandable microspheres (TEMs) for suede‐like leather manufacture was prepared by suspension polymerization using acrylonitrile (AN), methyl methacrylate (MMA) and vinyl acetate (VAC) as the shell monomers and iso‐pentane as the foaming component. The effect of the interfacial tension and viscosity of polymerization system on the particle size of TEMs, and in turn, the effect of the particle size of TEMs on the expansion temperature, expansion ratio and thermal response performance were investigated in detail. The results showed that increasing the interface tension and viscosity of the polymerization system was beneficial for preparing large size TEMs. Under the optimized conditions of 300 rpm, 25 wt% iso‐pentane dosage, and 9:3:1 mass ratio of AN/MAA/VAC, the TEMs shown above 100 μm particle size and 4 times expansion ratio at 150°C. Moreover, TEMs with 18% encapsulation ratio (Er) of the foaming component can complete foaming in the narrow temperature range (ΔT ≤ 10°C), showing a sensitive thermal response. The mixture of waterborne polyurethane and quantitative TEMs was coated on the surface of synthetic leather base, and a new type of suede‐like leather was obtained after foaming, which can substitute genuine suede leather. [ABSTRACT FROM AUTHOR]

Polymer materials containing oxime‐carbamate bonds show superior self‐healing ability under certain conditions. In this study, a series of dynamic oxime‐carbamate based PU‐D‐x (Polyurethane‐Dimethylglyoxime‐x) with different crosslinking degrees (x indicates the content of crosslinker based on the weight of solid content) were prepared, and the self‐healing together with the reprocessing characteristic was investigated. In situ variable temperature FTIR spectroscopy shows that the dissociation of oxime‐carbamate bonds occurred at 80°C and can be accelerated by the increasing temperature. With relatively lower cross‐linking degrees, these types of PU can be healed at low temperature and in a short time, for example, PU‐D‐0.3 can be completely healed at 80°C in 6 h, and PU‐D‐0.45 can be almost completely healed at 80°C in 9 h. With the increase of cross‐linking degree, the self‐repair of this kind of PU needs to be carried out at higher temperature and needs an extension of time. However, when the temperature increased to 100°C, the self‐healing time is greatly reduced to 3–5 h. Most interestingly, these types of crosslinked PUs showed expected reusing and reprocessing characteristics, even the PU‐D‐1.2 sample with the highest crosslinking degree can be completely reshaped and reprocessed under 120°C and 10 MPa pressure. [ABSTRACT FROM AUTHOR]

A type of polyester-based self-matting waterborne polyurethane (ESMWPU) with an excellent matte effect of 0.8° and transmittance of 78.5% for PVC artificial leather was synthesized. The influence of synthesis parameters, including R value, crosslinking and hydrophilic group content, on coating gloss and transmittance was investigated. Meanwhile, the properties necessary for applying water-based resins to plasticized PVC were detailed. The results demonstrated that R value, crosslinking degree and hydrophilic group content synergistically decided the morphological changes of latex particles during their film-forming process in three aspects: particle stiffness, three-dimensional structure and particle size, respectively. With optimized parameters of R = 1.9, TMP = 2 wt% and DMPA = 1.75 wt%, ESMWPU latex particles stabilized their spherical shapes without collapsing in the film-forming process and created a rough surface, resulting in a matte effect. In terms of application performance, good wetting and adhesion for ESMWPU to a plasticized PVC surface was achieved with a 2 wt% leveling agent load. Moreover, due to the high cohesion energy of ester bonds and intermolecular hydrogen bonds, this type of polyester-based ESMWPU also depicted admirable thermal adhesion resistance. All aforementioned results distinctly demonstrate a feasible yet promising paradigm for applying ESMWPU on PVC artificial leather. [ABSTRACT FROM AUTHOR]