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Polymers with high flexibility and high content renewable biomass materials have attracted particular attention. Plant‐derived trans‐cinnamic acid (CA) was introduced into the structure of epoxidized soybean oil to form trans‐cinnamated epoxidized soybean oil (ESOCA). ESOCA with multi‐cinnamate groups was cured via [2 + 2] cycloaddition photo‐polymerization that with no need of photoinitiator, while acrylated epoxidized soybean oil (ESOAA) was photocured via free radical photopolymerization for comparison. The successful synthesis of ESOCA and ESOAA resin was proved by Fourier transform infrared, proton nuclear magnetic resonance, and gel permeation chromatography results. ESOCA is more environmentally friendly than ESOAA for that trans‐CA volatility is much lower than acrylic acid during synthesis process. Notably, UV‐cured ESOCA samples had a higher tensile strength at break and a 14.75 times elongation at break of that of UV‐cured ESOAA samples, showing that [2 + 2] cycloaddition photo‐polymerization is a good strategy to prepare flexible materials. Performances of ESOCA as coating on flexible PET film were also better than those of ESOAA, especially the flexibility, adhesion, and UV shielding performance. This study may open up a new way for design and synthesize flexible high performance polymer from renewable biomass materials. [ABSTRACT FROM AUTHOR]

ZnO quantum dots@SiO2 (ZnO QDs@SiO2) was synthesized by a modified sol–gel method, and then added to polyvinyl alcohol (PVA) to form an ink-absorbing coating with ultraviolet shielding performance on poly(ethylene terephthalate) (PET) films. A layer of silica encapsulated on the surface of ZnO QDs not only reduces the photocatalytic activity significantly, but also prevents the agglomeration of ZnO QDs in aqueous solution. The UV-vis transmittance spectrum of the as-prepared ink-absorbing coating displayed excellent shielding performance in the ultraviolet region (<355 nm) and high transmittance in the visible region. Even when exposed to 30 W ultraviolet for 100 h, no obvious changes were observed in its UV-vis transmittance spectrum, showing long-term durability. Notably, the ink absorption of the ink-absorbing coating prepared using ZnO QDs@SiO2 is higher than that of the ink-absorbing coating prepared using commercially available silica. Therefore, a durable, highly transparent and ultraviolet shielded inkjet printing coating on PET can be prepared with ZnO QDs@SiO2 nanoparticles. [ABSTRACT FROM AUTHOR]

In this report, we have established a novel and efficient method for selectively synthesizing either vinyl sulfides or 2-methylbenzothiazoles from the reaction of CaC 2 and disulfides. The selective synthesis of these two distinct products can be controlled by simply adjusting the amount of K 2 S. The underlying reaction mechanism has been thoroughly investigated through control experiments, HRMS, and FTIR, which collectively support the pivotal role of a trisulfur radical anion. This radical species, generated in situ from K 2 S, is essential for the homolytic cleavage of the S-S bonds in a catalytic manner. Additionally, the trisulfur radical anion also acts as an effective mediator for activating the vinyl group of 2-aminophenyl vinyl sulfides, facilitating the crucial intramolecular cyclization required to produce 2-methylbenzothiazoles. Moreover, CaC 2 not only serves as an acetylene source but also creates the basic conditions essential for the selective formation of vinyl sulfides. This methodology demonstrates broad substrate compatibility and excellent functional group tolerance, significantly enhancing its practical utility in diverse synthetic applications.