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This study successfully developed a bio-based, photocurable, anionic–nonionic dual-functional chain extender, and sulfonated cardanol-based polyethylene glycol (SCP), derived from renewable resources—cardanol and polyethylene glycol—for application in waterborne polyurethane dispersions (WPUDs). Utilizing SCP as a chain extender, WPUDs were prepared through a typical acetone process with poly(butylene adipate) (PBA), isophorone diisocyanate (IPDI), and ethylene diamine (EDA) at a constant NCO/OH ratio of 1:1. This research focused on the effects of polyethylene glycol molecular weight and SCP dosage on the particle size, stability, and film-forming properties of the WPUD. Optimal dispersion stability and film-forming performance were achieved with a polyethylene glycol molecular weight of 1500 and a PBA to SCP molar ratio of 4:1, yielding a particle size of 0.326 ± 0.010 μm and excellent storage stability over six months. The resulting WPU coatings exhibited a tensile strength of 11.4 MPa, which increased to 16.8 MPa after UV irradiation owing to the formation of a semi-interpenetrating network via the photopolymerization of cardanol's unsaturated side chains. UV cross-linking also enhanced water resistance, reducing the water absorption rate (WAR) from 18.68% to 4.21% and the water vapor transmission rate (WVTR) from 6.59 × 10−5 g·m⁻¹·Pa⁻¹·d⁻¹ to 2.26 × 10⁻⁵ g·m⁻¹·Pa⁻¹·d⁻¹, while also improving thermal stability. These findings demonstrate that SCP offers a sustainable and effective solution for developing high-performance WPU coatings. [ABSTRACT FROM AUTHOR]

A natural extract, i.e., urushiol, was employed to effectively cross-link and modify commercial wet-cured polyurethane acrylic resin. Comprehensive characterization of the paint film was performed using techniques such as FTIR, SEM, and TGA. The results indicated that the incorporation of urushiol significantly increased the cross-linking density of the resin, which in turn enhanced the film-forming properties, mechanical strength, and thermal stability of the paint film. Additionally, the study discovered that under isothermal conditions, the dynamic moduli (G′ and G″) of the paint film are related to the gel point frequency by a power law, aligning with the predictions of percolation theory. The application of the autocatalytic model has provided a novel approach to studying non-isothermal kinetic reactions, offering valuable insights for process optimization and further development of urushiol-based polyurethane. [ABSTRACT FROM AUTHOR]

SUMMARY: While it is known that increased dissolved CO2 concentrations and rising sea surface temperature (ocean warming) can act interactively on marine phytoplankton, the ultimate molecular mechanisms underlying this interaction on a long‐term evolutionary scale are relatively unexplored. Here, we performed transcriptomics and quantitative metabolomics analyses, along with a physiological trait analysis, on the marine diatom Thalassiosira weissflogii adapted for approximately 3.5 years to warming and/or high CO2 conditions. We show that long‐term warming has more pronounced impacts than elevated CO2 on gene expression, resulting in a greater number of differentially expressed genes (DEGs). The largest number of DEGs was observed in populations adapted to warming + high CO2, indicating a potential synergistic interaction between these factors. We further identified the metabolic pathways in which the DEGs function and the metabolites with significantly changed abundances. We found that ribosome biosynthesis‐related pathways were upregulated to meet the increased material and energy demands after warming or warming in combination with high CO2. This resulted in the upregulation of energy metabolism pathways such as glycolysis, photorespiration, the tricarboxylic acid cycle, and the oxidative pentose phosphate pathway, as well as the associated metabolites. These metabolic changes help compensate for reduced photochemical efficiency and photosynthesis. Our study emphasizes that the upregulation of ribosome biosynthesis plays an essential role in facilitating the adaptation of phytoplankton to global ocean changes and elucidates the interactive effects of warming and high CO2 on the adaptation of marine phytoplankton in the context of global change. Significance Statement: The up‐regulation of ribosome biosynthesis plays an essential role in facilitating the adaptations of phytoplankton to ocean global change. [ABSTRACT FROM AUTHOR]

The development of more recyclable materials is a key requirement for a transition towards a more circular economy. Thanks to exchange reactions, vitrimer, an attractive alternative for recyclable materials, is an innovative class of polymers that is able to change its topology without decreasing its connectivity. In this work, a bisphenol compound (VP) was prepared from saturated cardanol, i.e., 3−pentadecylphenol and vanillyl alcohol. Then, VP was epoxidized to obtain epoxide (VPGE). Finally, VPGE and citric acid (CA) were polymerized in the presence of catalyst TBD to prepare a fully bio−based vitrimer based on transesterification. The results from differential scanning calorimetry (DSC) showed that the VPGE/CA system could be crosslinked at around 163 °C. The cardanol−derived vitrimers had good network rearrangement properties. Meanwhile, because of the dynamic structural elements in the network, the material was endowed with excellent self−healing, welding, and recyclability. [ABSTRACT FROM AUTHOR]

Although the diverse impacts of elevated dissolved CO2 and warming on organisms within various trophic levels in marine food webs are well documented, we have yet to explore the biological links across different levels of biological organization from primary producers to secondary producers on an evolutionary time scale in a high‐CO2 ocean. Here, we cultured a model marine diatom Phaeodactylum tricornutum (primary producer) in predicted future high‐CO2 and/or warming conditions for ~ 1250 d with an experimental evolution approach and then fed them to the clam Coelomactra antiquata (secondary producer). We present an in‐depth multi‐omics analysis along the methylome (primary producer)–transcriptome (primary producer)–metabolome (primary producer)–metabolome (secondary producer) continuum. Our results showed that the downregulated terpenoid backbone biosynthesis in the methylome and transcriptome lead to decreased pyruvate levels and upregulation of some pathways (such as phenylalanine metabolism) in the metabolome of the primary producer in the long‐term warming conditions. These changes in metabolomic profile in the primary producer were then transferred to the secondary producer, resulting in changes in abundance of some metabolites, such as decreases in pyruvate, and in pyruvaldhyde (also known as methylglyoxal), and increases in 2‐hydroxylamino‐4,6‐dinitrotoluene. Our study provides a new insight into the molecular mechanisms underlying the trophic transfer from primary to secondary producers in a future high‐CO2 ocean and may provide more accurate projections of marine ecosystem services and functions over the next century. [ABSTRACT FROM AUTHOR]

We have investigated a self-healing thermally conductive Ethylene-vinyl acetate (EVA) hot melt adhesive (NAEDS, which denotes the addition of nano-alumina and disulfide bonded EVA hot melt adhesives) that can be used to effectively solve adhesive layer separation problem in photovoltaic (PV) modules and the difficulty of recycling. More specifically, we used diallyl disulfide as a cross-linking agent for EVA and alumina nanofillers as a reinforcing phase. The nano alumina filler gave the EVA better thermal conductivity. We used FTIR, SEM, and DSC to characterize and analyze NAEDS properties. The disulfide bonds in NAEDS underwent a rearrangement reaction under ultraviolet light, resulting in the self-healing of the resin (self-healing efficiency of 78.8%). The added nano alumina not only reduced the resin curing activation energy, improving its curing performance but also enhanced its thermal conductivity, achieving a 2.61 W/(m*k) thermal conductivity coefficient. The overall NAEDS performance is improved. [ABSTRACT FROM AUTHOR]

The over-exploitation of finite fossil resources and/or the increased environmental and sustainable awareness inspire scientists and technologists to search for inexpensive alternatives from renewable chemicals. Phenol formaldehyde (PF) resins, the oldest type of synthetic polymers with good mechanical properties and heat resistance, are widely used in the production of coatings, laminates, molding compositions, and glues. Here, biobased urushiol-derived PF resins were synthesized from the alkali-catalyzed reaction between urushiol and formaldehyde. The chemical compositions and molecular structures of resole resins were characterized by carbon-13 nuclear magnetic resonance and Fourier transform infrared spectroscopy, and their curing behaviors were studied by differential scanning calorimetry. The as-prepared urushiol-derived resole resins had methylol (Ph-[CH.sub.2]OH), ortho- and para-hemiformal groups (Ph-[CH.sub.2]O[CH.sub.2]OH), and the para-para/ortho-para/ortho-ortho links of methylene groups (Ph-[CH.sub.2]-Ph), whereas the resole resins had low curing temperatures at about 100-113[degrees]C. Additionally, given the long side alkyl group moiety on the aromatic rings of urushiol, the films of cured urushiol-derived resole resins had low glass transition temperatures of 132 [+ or -] 2[degrees]C. Furthermore, the as-prepared urushiol-derived coatings exhibited excellent physical and mechanical properties. KEYWORDS chemical structures, Chinese lacquer, curing characteristics, physical and mechanical properties, urushiol, urushiol-derived PF resins, 1 | INTRODUCTION With many advantages, such as excellent mechanical strength, good heat and moisture resistance, and advanced ablative properties, phenol formaldehyde (PF) resins have found wide applications in microelectronics, [...]

Due to layer by layer printing, the interlayer adhesion of resin used in extrusion-based additive manufacturing (AM) is poor, while thermal curing affects the accuracy of the resin. Therefore, methods of photo-curing and nanomodification were used in this work to improve the adhesion between layers and the overall performance of AM resins. Specifically, ethylene-vinyl acetate (EVA) copolymer with dual curing agent of benzophenone/triallyl isocyanurate (BP/TAIC) and nano-silica (NS) were introduced. The results of light transmittance, scanning electron microscopy and gel content test showed that BP/TAIC with NS were proved to be able to improve the curing process of EVA. The filling of a small amount of NS did not act as ultraviolet light barrier, but instead improved the photo-curing of the resin and reduced the amount of agents. UV curing also improved the adhesion between layers of EVA resin. The tensile strength was 7.1% higher than that of EVA/NS/BT without curing. At the same time, due to good interface bonding and dispersion, the thermal conductivity of resin improved from 0.212 W/m*k to 0.252 W/m*k. A 16.1% raise in tensile strength and a 10.0% increase in the volume resistivity were demonstrated for the 3.0 wt% NS. Furthermore, this resin is potential to be used in AM. KEYWORDS additive manufacturing, ethylene-vinyl acetate, nano-silica, photo-curing, property, 1 | INTRODUCTION Additive manufacturing (AM) often referred to as 3D printing. Unlike traditional manufacturing processes, materials were stacked layer by layer to fabricate three-dimensional parts during AM. [1,2] There [...]

In this study, polyamidoamine (PAMAM) was added to raw lacquer in different proportions, and the curing process and properties of lacquer film were investigated by using thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM), To investigate the cross-linking state between PAMAM and urushiol, NMR was used in this study. The experiments revealed that the comprehensive mechanical properties of modified-film, especially the impact strength, were significantly improved. In addition, the touch-free drying time of lacquer film decreased, and its alkali resistance was improved due to the cross-linking of PAMAM and urushiol molecules. KEYWORDS corrosion resistance, lacquer, mechanical properties, modification, polyamidoamine, 1 | INTRODUCTION Raw lacquer, a natural polymer, is regarded as a promising functional coating for various objects in view of its high hardness, good adhesion, smooth appearance, and excellent [...]

Urushiol, the main component of the natural product of raw lacquer, can react with ester easily owing to its two adjacent phenolic hydroxyls, and urushiol-ester compounds can polymerize further attributing to its unsaturated side chain. In this work, poly(urushiol borate) (PUB) was coated on the surface of polystyrene (PS) microspheres by transesterification between urushiol and tributyl borate. Then, the core-shell composite microspheres of polystyrene@poly(urushiol borate) (PS@PUB) were obtained. Finally, we used a general method to synthesize anisotropic grenadelike Janus composite particles of PUB/PS, that is, the coreshell composite microspheres of PS@PUB were swelled assisted protrusion in the emulsion of organic monomer and water. The morphologies of PUB/PS Janus composite particles could be tuned by changing the swelling time and the dosage of organic monomer. POLYM. ENG. SCI., 58:23042310, 2018., INTRODUCTIONJanus composite particles are regarded as one of the most complicated colloidal particles in existence [1]. In recent years, controlling the structure and composition of Janus composite particles have being [...]