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Dual response polyurethane nanocapsules consisting of a hydrophilic core are synthesized via interfacial polyaddition of the diisocyanate monomers and different diols (VA‐060 and glycols) in inverse miniemulsion process. The presence of the water‐soluble NIR dye in the core and azo‐bonds in the polymer shell allows the selective release of encapsulated material triggered by temperature or NIR light. The capsules are characterized by transmission electron microscopy (TEM) and dynamic light scattering (DLS). The capsule degradation under external stimuli, like temperature and NIR light, is confirmed microscopically by TEM. Macroscopic evidence of the capsule cleavage was achieved by the incorporation of the chemical into the capsule core, and subsequent treatment of the capsules with NIR laser in the presence of the suitable reagent outside the capsules. A color‐forming chemical reaction occurred after the shell opening. The reactions were easily detected by visual observation of a color change and by UV–Vis spectroscopy. [ABSTRACT FROM AUTHOR]

Clostridium ragsdalei was found to produce (S)-2-hydroxyisovalerate (2-HIV) as a novel product in addition to acetate, ethanol, and d-2,3-butanediol in heterotrophic (d-xylose), autotrophic (CO), and mixotrophic (d-xylose + CO) conditions. Mixotrophic batch processes in stirred-tank bioreactors with continuous gassing resulted in improved production of this alpha-hydroxy acid compared to batch processes solely with either d-xylose or CO. The maximal CO uptake rate was considerably reduced in mixotrophic compared to autotrophic processes, resulting in a concomitant decreased total CO2 production. Simultaneous conversion of 9.5 g L−1 d-xylose and 320 mmol CO enabled the production of 1.8 g L−1 2-HIV in addition to 1.1 g L−1 d-2,3-butanediol, 2.0 g L−1 ethanol, and 1.8 g L−1 acetate. With reduced initial d-xylose (3.1 g L−1), l-valine production started when d-xylose was depleted, reaching a maximum of 0.4 g L−1 l-valine. Using l-arabinose or d-glucose instead of d-xylose in mixotrophic batch processes reduced the 2-HIV production by C. ragsdalei. Considerable amounts of meso-2,3-butanediol (0.9–1.3 g L−1) were produced instead, which was not observed with d-xylose. The monomer 2-HIV can form polyesters that make the molecule attractive for application as bioplastic (polyhydroxyalkanoates) or new composite material. [ABSTRACT FROM AUTHOR]

In this study, we utilized nanocomposites prepared from nanosilica (SiO2) and various polythiophene derivatives as enhancement additives for acrylic coatings. The nanocomposites were synthesized in a nitrogen environment using FeCl3 as a catalyst in a chloroform solvent. The weight ratio of nanosilica to monomers was 2/1, specifically for the compounds (5-benzo[d]thiazol-2-yl)-7-methoxy-2-(thiophen-3-yl)benzo[d]oxazole (P1), 3-(2-benzothiazolyl)thiophene (P2), and 5-(benzo[d]thiazol-2-yl)-2-(thiophene-3-yl)benzo[d]oxazole (P3). Analysis techniques including IR, TGA, SEM, and UV–Vis were employed to demonstrate the formation of polythiophenes on the surface of the nanosilica. The presence of polythiophenes on the nanosilica broadened the UV absorption region. Upon adding the nanocomposites to acrylic coatings, the UV absorption intensity of the coatings was increased. Notably, the coating containing SiO2-P3 nanocomposite exhibited the highest abrasion resistance among all the investigated samples. By varying the content of SiO2-P3 nanocomposite, we observed enhanced abrasion resistance, adhesion, pencil hardness, and gloss of the acrylic coating. The maximum values were achieved when the content of SiO2-P3 nanoparticles was 2 wt.%. The SiO2-P3 nanoparticles were uniformly dispersed in the acrylic coatings, leading to an improvement in the coating's sunlight-reflective ability. Consequently, the acrylic/SiO2-P3 nanocomposite coatings exhibited potential for outdoor applications, particularly as UV-resistant coatings. [ABSTRACT FROM AUTHOR]

Medium chain‐length polyhydroxyalkanoates (mcl‐PHAs) are efficiently synthesized from fatty acids. It was hypothesized that under non‐axenic conditions, the anti‐microbial properties of fatty acids would reduce growth of microbial competitors and allow Pseudomonas putida LS46 to dominate the population resulting in non‐sterile mcl‐PHA production. Non‐sterile batch and fed‐batch cultures produced similar final mcl‐PHA content, monomer composition, and productivity during 24–27 h cultivations when compared to sterile control cultures for initial octanoic acid concentrations ranging from 5 to 40 mM at an initial pH of 6.5. In the absence of a P. putida inoculum, growth was eventually observed in non‐sterile medium after a lag period of up to 120 h, the length of which was dependent on the octanoic acid concentration. The efficacy of prolonged non‐sterile cultivation was tested using a sequential batch reactor (SBR). After 28 days (672 h), 1.62 g L−1 of total biomass was observed, of which the mcl‐PHA content was 47%. This resulted in a PHA titer of 0.77 g L−1, and a volumetric PHA productivity of 32 mg L−1 h−1. The polymer composition remained stable throughout at 87.0 ± 2.7% C8 monomers, and short‐chain length (scl‐) monomers were not detected. This study is the first of its kind to report that purely mcl‐PHAs were produced after prolonged periods in a non‐sterile environment and demonstrate that medium chain‐length fatty acids exert a strong selective pressure toward organisms that synthesize mcl‐PHA. This suggests an opportunity for mcl‐PHA production in open continuous cultivation, which could reduce both fixed and operating costs. [ABSTRACT FROM AUTHOR]

Low‐strain cyclic olefin monomers, including five‐membered, six‐membered, eight‐membered, and macrocyclic rings, have been recently exploited for the synthesis of depolymerizable polyolefins via ring‐opening metathesis polymerization (ROMP). Such polyolefins can undergo ring‐closing metathesis depolymerization (RCMD) to regenerate their original monomers. Nevertheless, the depolymerization behavior of polyolefins prepared by ROMP of seven‐membered cyclic olefins, an important class of low‐strain rings, still remains unexplored. In this study, we demonstrate the chemical recycling of polyheptenamers to cycloheptene under standard RCMD conditions. Highly efficient depolymerization of polyheptenamer was enabled by Grubbs' second‐generation catalyst in toluene. It was observed that the monomer yields increased when the depolymerization temperature increased and the starting polymer concentration was reduced. A near‐quantitative monomer regeneration (>96%) was achieved within 1 h under dilute conditions (20 mM of olefins) at 60°C. Moreover, polyheptenamer exhibited a decomposition temperature above 430°C, highlighting its potential as a new class of thermally stable and chemically recyclable polymer materials. [ABSTRACT FROM AUTHOR]

The control of the regioselectivity of metal‐catalyzed α‐olefins polymerization is of everlasting interest. Most nickel and palladium catalysts show high regioselectivity involving 2,1‐insertion of α‐olefins and 1,ω‐enchainment chain‐straightening, especially α‐diimine nickel catalysts. In this contribution, we report extremely rare regioselective chain‐straightening polymerization of α‐olefins through 2,ω‐enchainment using unsymmetrical amine–imine nickel catalysts. The polymerizations of α‐olefins (1‐hexene, 1‐octene, and 1‐decene) were studied in detail, and the effects of catalyst structure, reaction temperature, and monomer concentration on the polymerization activity and the regioselectivity were examined. The unsymmetrical N‐substituents of the amine–imine nickel catalysts play a crucial role in the regioselectivity. High regioselectivity involving 80.4% 1,2‐insertion and 84.5% 2,ω‐enchainment is realized to produce amorphous polyolefins without melting temperatures. [ABSTRACT FROM AUTHOR]

The development of polymer carriers for systems of prolonged and controlled release of substances, particularly drugs, into the action environment is a relevant task in polymer chemistry and technology. This aims to solve the problem of reducing the effective dose of a medical drug administered into the body of a person or animal. The latest achievements in the field of creating such carriers in the form of spherical particles based on 2- hydroxyethyl methacrylate and polyvinylpyrrolidone (co)polymers are analyzed and summarized. The working principles and advantages of such systems are described. The research of the synthesis regularities, structure, properties and perspectives of application of granular hydrogels based on 2-hydroxyethyl methacrylate and its copolymers with polyvinylpyrrolidone was analyzed. The mixture of decanol and cyclohexanol as a solvent for the monomer phase is substantiated. Based on the analysis of kinetic studies, the optimal technological parameters for the suspension polymerization of 2-hydroxyethyl methacrylate with polyvinylpyrrolidone were selected, and the possibility of regulating the dispersion characteristics of copolymers via changes in the technological synthesis modes was confirmed. The results of studies on the sorption-desorption properties of copolymers concerning model substances and drugs are described. The possibility of directed regulation of sorption capacity and drug release rate through changes in copolymer composition was confirmed. Methods for increasing the sorption capacity of hydrogels for drugs are proposed. [ABSTRACT FROM AUTHOR]

Highly alkaline hydrogels are gaining increasing attention in building materials research. Specifically, cationic alkaline hydrogels based on diallyldimethylammonium hydroxide (DADMAOH) as the monomer have been effectively used to seal water-bearing cracks or serve as coupling media for electrochemical chloride extraction. However, the residual halogen content and challenges in scaling up monomer production have hindered broader application. Attempts to use a commercially available cation-selective membrane for ion exchange achieved up to 90% chloride-to-hydroxide switch, but the approach proved ineffective due to significant monomer decomposition during the process. By contrast, neutral gels and gel particles can be readily prepared from diallyldimethylammonium chloride (DADMAC) in large quantities and with a wide range of compositions. It is demonstrated here that these neutral gel particles undergo inverse static anion exchange when suspended in NaOH solution, generating DADMAOH particles with residual halide contents of <0.3%, without the need for ion-selective or dialysis membranes. This corresponds to an up to 100-fold reduction in residual chloride content compared to particles produced directly from alkaline monomer solutions, thereby significantly enhancing the efficiency of hydroxide ion release. The swelling behaviour of the particles is primarily influenced by the initial monomer concentration, while conductivity remains largely unaffected, indicating that charge transport occurs mainly along the particle surface. Despite the pronounced increase in swelling with decreasing particle radii, the specific conductivity of 2.8 Ω−1 m−1 is still sufficient for their use as coupling media in concrete applications. In summary, the alkaline particles prepared via inverse static anion exchange meet all necessary requirements for building materials applications, offering a broader range of tuneable properties and greater ease of production compared to gels or particles derived from DADMAOH. [ABSTRACT FROM AUTHOR]

In this study, new data are presented on the behavior of Pd nanoparticles (NPs) stabilized in naphthalenebased polymers containing different functional groups (hydroxyl, sulfonate, and nitro groups) in cross-coupling reactions (Suzuki, Sonogashira, and Heck). Polymers were synthesized by the direct knitting strategy using naphthalene or naphthol as the monomers and iron chloride as the polymerization catalyst with following sulfonation or nitration. The resulting polymeric materials were used to support the formation of Pd NPs. It was shown that the sizes of Pd NPs depend on the relative hydrophobicity of the polymeric environment. All the catalytic materials were shown to be highly active and selective: using low amounts of catalysts (0.2 mol.% of Pd with respect to an aryl halide) in environmentally benign solvents (ethanol, dimethyl sulfoxide) and in the absence of any ligands and co-catalysts more than 90 % conversion was achieved in 60 min in the case of Suzuki and Sonogashira cross-coupling. Catalytic activity was found to go through a maximum corresponding to the sizes of Pd NPs of about 10 nm. The Heck cross-coupling required the use of N,N-dimethylformamide as a solvent and the addition of triethylamine, which allowed achieving more than 80 % aryl halide conversion for 3 h. [ABSTRACT FROM AUTHOR]

Silicone hydrogels are pivotal materials used in contact lenses, biomedicine, and electronic devices, where oxygen permeability and equilibrium water content (EWC) are essential attributes. Generally, an increase in silicone content boosts oxygen permeability but diminishes EWC, presenting a notable trade‐off challenge. In this study, a solvent incorporation method that significantly elevates oxygen permeability without markedly affecting EWC is introduced. Among various solvents, isopropanol incorporation notably enhances oxygen permeability (101 barrer) while maintaining an EWC of 56.0%. This improvement is attributed to enhanced connectivity within the silicone network. Additionally, it is discovered that incorporating siloxane nanoparticles (SNPs) further increases the connectivity of the silicone network, offering a more pronounced improvement in oxygen permeability than solvent alone. However, excessive SNP addition can lead to large phase separation, resulting in decreased transmittance, lower EWC, and increased mechanical strength. Optimizing a transmittance of over 99%, SNP addition achieves a silicone hydrogel with an oxygen permeability of 125 barrer and an EWC of 49.5%, surpassing many advancements reported in the literature. [ABSTRACT FROM AUTHOR]

Atomic scaling of cobalt‐based catalysts is the feasible and sustainable approach for selective oxidation of biomass‐derived 5‐hydroxymethylfurfural (HMF) to produce bio‐plastic monomer of 2,5‐furandicarboxylic acid (FDCA) under mild conditions. Here, a high‐efficiency dual single‐atomic Co/Cu supported on nitrogen‐doped carbon (a‐Co/Cu‐NC) is constructed. Leveraging exceptional oxygen activation ability, the Co/Cu dual‐atomic‐sites can accelerate the HMF oxidation, suppressing by‐product formation mediated by reactive oxygen species (ROS) in low‐oxygen environments. This leads to enhanced FDCA selectivity with a yield of 98% and a production rate of 298.8 mmolFDCA gmetal−1 h−1 under ambient conditions. Comprehensive experiments and density functional theory (DFT) calculations demonstrate that long‐range interactions between Co and Cu sites optimize reactant adsorption and lower energy barriers for •O2− and HMFCA formation. [ABSTRACT FROM AUTHOR]

Fluorosilicone rubber is essential for sealing in extreme temperatures and non‐polar environments due to its exceptional adaptability. However, achieving a high yield of fluorosilicone polymers with medium and high fluorine content remains a challenge. Herein, a facile gradient strategy is developed that involves modifying the method of cyclic monomer addition based on the rate of ring‐opening polymerization (ROP), to improve yield and adjust fluorine content precisely. The polymerization process is designed and tailored based on the reaction rates of anionic ring‐opening polymerization (AROP) and cationic ring‐opening polymerization (CROP) via an efficient gradient strategy. The effects of the polymerization process on the viscosity and yield of vinyl fluorosilicone polymers and hydrofluorosilicone polymers are investigated and optimized. Notably, the as‐prepared vinyl‐terminated fluoromethylsilane with 60% fluorine content (FMS‐Vi‐60F) has a high yield (86.6%) and high viscosity (150 000 mPa·s) in a short reaction time, which is superior to previous methods. Clearly, the gradient ring‐opening method developed in this work provides a facile and efficient synthesis for fabricating fluorosilicone polymers with a high yield and tunable fluorine content. [ABSTRACT FROM AUTHOR]

The resin infiltration concept is one of the most widely used minimally invasive restorative techniques in restorative dentistry with the most outstanding therapeutic effect, and it is also one of the key research directions in restorative dentistry. “Infiltration resin” is the specialty restorative material for the technology, which is the key factor to success. The specialized restorative material is commonly known as “infiltrant/infiltration resins” “resins infiltrant” “infiltrant” or “resins,” which will be consistently referred to as “infiltration resins” throughout the article. The paper aims to provide a comprehensive overview of infiltration resins by introducing the development of their therapeutic mechanisms, basic components, current challenges, and future trends, Based on existing literature, we analyze and compare how changes in the base monomer's structure and ratio affect the effectiveness of infiltration resins, from the material's structure‐effective relationship. After compiling the information, the existing solution strategies have been listed to offer substantial support and guidance for future research endeavors. [ABSTRACT FROM AUTHOR]

A new design policy to synthesize nanogel molecules having desired dimensions under unperturbed state is proposed. Miniemulsion copolymerization of vinyl and divinyl monomers, both conventional free‐radical polymerization and ideal living polymerization, is used to illustrate the method. For the network formation dynamics, the newly proposed model that takes into account the size and structure dependence of cross‐linking/cyclization reactions is employed. The master curve relationship that indicates the maximum average dimensions for randomly cross‐linked networks is used as a guideline and the network dimension is controlled by the magnitude of network maturity index NMI, which is the average number of cycle rank per primary chain. By appropriately sizing the NMI, it is possible to synthesize network polymers with dimensions equal to or greater than the maximum dimensions achievable with a homogeneous, randomly cross‐linked network polymer of the same cycle rank and molecular weight. The current strategy of designing and controlling 3D size is applicable regardless of the reaction mechanism of network formation and will also be applied to the synthesis of macro‐gels. [ABSTRACT FROM AUTHOR]

Polyamide plays a pivotal role in engineering thermoplastics. Constrained by the harsh conditions and arduous procedures for its industrial synthesis, developing facile synthesis of polyamides is still challengeable and holds profound significance. Herein, we successfully utilized water as one of the monomers to synthesize functional polyamides under ambient conditions. A powerful multicomponent polymerization of water, isocyanides, and chlorooximes was established in phosphate‐buffered saline. Soluble and thermally stable polyamides with high weight‐average molecular weights (up to 53 900) were obtained in excellent yields (up to 95 %). The polymerization exhibits unique polymerization‐induced emission characteristics, successfully converting non‐emissive monomers into unconventional emissive polymers. Notably, the resultant polyamides could undergo effective post‐modification via the hydroxyl‐yne click reaction. By incorporating various functional groups into the polyamide, its emission color could be fine‐tuned from blue to green and to red. Remarkably, the refractive index (n) of the polyamide at 589 nm could be increased from 1.6173 to 1.7227 and the Δn could be unprecedentedly as high as 0.1054 for non‐heavy atom‐containing polymers after post‐modification, and its micron‐thick films exhibited excellent transparency in the visible region. Thus, this work not only establishes a powerful polymerization toward novel polyamides but also opens up an avenue for their versatile functionalization. [ABSTRACT FROM AUTHOR]

This feature article delves into the realm of α- L -threose nucleic acid (TNA), an artificial nucleic acid analog characterized by a backbone comprising an unconventional four-carbon sugar, α- L -threose, with phosphodiester linkages connecting at the 2′ and 3′ vicinal positions of the sugar ring. Within this article, we encapsulate the potential, progress, current state of the art, and persisting challenges within TNA research. Kicking off with a historical overview of xeno nucleic acids (XNAs), the discussion transitions to the compelling attributes and structure–property relationships of TNAs as advanced tools when contrasted with natural nucleic acids. Noteworthy aspects such as their advantageous spatial arrangements of functional groups around the sugar ring, stable Watson–Crick base pairing, high binding affinity, biostability, biocompatibility, and in vivo bio-safety are highlighted. Moreover, the narrative unfolds the latest advancements in chemical and biological methodologies for TNA synthesis, spanning from monomer and oligomer synthesis to polymerization, alongside cutting-edge developments in enzyme engineering aimed at bolstering large-scale TNA synthesis for in vitro selection initiatives. The article sheds light on the evolution of TNA aptamers over time, expounding on the tools and selection techniques engineered to unearth superior binding aptamers and TNA catalysts. Furthermore, the article accentuates the recent applications of TNAs across diverse domains such as molecular detection, immunotherapy, gene therapy, synthetic biology, and molecular computing. In conclusion, we summarize the key aspects of recent TNA research, address persisting gaps and challenges, and provide crucial insights and future perspectives in the dynamic domain of TNA research. [ABSTRACT FROM AUTHOR]

SUMOylation regulates numerous cellular stress responses, yet targets in the apoptotic machinery remain elusive. We show that a single, DNA damage-induced monoSUMOylation event controls PIDDosome (PIDD1/RAIDD/caspase-2) formation and apoptotic death in response to unresolved DNA interstrand crosslinks (ICLs). SUMO-1 conjugation occurs on conserved K879 in the PIDD1 death domain (DD); is catalyzed by PIAS1 and countered by SENP3; and is triggered by ATR phosphorylation of neighboring T788 in the PIDD1 DD, which enables PIAS1 docking. Phospho/SUMO-PIDD1 proteins are captured by nucleolar RAIDD monomers via a SUMO-interacting motif (SIM) in the RAIDD DD, thus compartmentalizing nascent PIDDosomes for caspase-2 recruitment. Denying SUMOylation or the SUMO-SIM interaction spares the onset of PIDDosome assembly but blocks its completion, thus eliminating the apoptotic response to ICL repair failure. Conversely, removal of SENP3 forces apoptosis, even in cells with tolerable ICL levels. SUMO-mediated PIDDosome control is also seen in response to DNA breaks but not supernumerary centrosomes. These results illuminate PIDDosome formation in space and time and identify a direct role for SUMOylation in the assembly of a major pro-apoptotic device. After DNA damage a caspase-2 activating PIDDosome can be formed. Here the authors identify sequential post-translational modifications of PIDD1 which orchestrate PIDDosome formation in space and time. [ABSTRACT FROM AUTHOR]

The synthesis of fully fused π‐conjugated cycloarenes embedded with nonbenzenoid aromatics is challenging. In this work, the first example of four‐membered ring‐embedded cycloarene (MF2) was designed and synthesized in single‐crystal form by macrocyclization and ring fusion strategies. For comparison, single bond‐linked chiral macrocycle MS2 without two fused four‐membered rings and its linear‐shaped polycyclic benzenoid monomer L1 were also synthesized. The pronounced anti‐aromaticity of four‐membered rings significantly adjusts the electronic structures and photophysical properties of cycloarene, resulting in an enhancement of the photoluminescence quantum yield (PLQY) from 10.66 % and 10.74 % for L1 and MS2, respectively, to 54.05 % for MF2, which is the highest PLQY among the reported cycloarenes. Notably, owing to the embedded anti‐aromatic four‐membered rings that reduce structural displacements, MF2 exhibits an ultra‐narrowband emission with a single‐digit full‐width at half‐maximum (FWHM) of only 7 nm (0.038 eV), which sets a new record among all reported organic narrowband luminescent molecules, and represents the first example of ultra‐narrowband emission in conventional polycyclic aromatic hydrocarbons (PAHs) devoid of heteroatoms. [ABSTRACT FROM AUTHOR]

The uncontrollable lithium (Li) dendrites growth and complex electrode/electrolyte interface (EEI) problems are hindering the further application of high energy density lithium metal batteries (LMBs) in practice. Herein, a bilayer heterostructure gel polymer electrolyte (BGPE) is designed by directly curing functional boron‐containing monomers on the electrode surface to ensure excellent conductivity while solving the interface problems, achieving durable high voltage resistance and Li dendrites suppression. The unoccupied p‐orbital boron moiety of the 3D crosslinked network in BGPE not only improves the Li+ transference number (0.78), but also enhances the interfacial stability of the Li metal and inhibits the dendrites growth by anchoring PF6− anions and regulating the uniform Li deposition, thus ensuring a long cycle for Li/BGPE/Li cells. In addition, the functional additives tris(trimethylsilyl) phosphite and tris(pentafluorophenyl)borane can preferentially oxidize and decompose to form stable B, F, and Si‐rich EEIs, and effectively regulate the uniform growth of EEI. Thus, the LiNi0.5Co0.2Mn0.3O2/BGPE/Li and LiFePO4/BGPE/Li full cells exhibit stable cycling and excellent rate performance. This work provides a guiding design direction to address the EEI problems for high energy density LMBs. [ABSTRACT FROM AUTHOR]

Combination of borane and diaminoferrocene monomers by Si/B exchange condensation reactions afforded either diazabora-[3]ferrocenophanes or, via stepwise processes, larger macrocycles and a series of linear oligomers. Additional incorporation of p-phenylene moieties in the backbone yielded alternating concatenation. [ABSTRACT FROM AUTHOR]

The origin of stereocontrol in ring opening polymerization (ROP) of racemic lactide (rac‐LA) promoted by achiral aluminium‐based catalysts has been explained through DFT calculations combined with a molecular descriptor (%VBur) and the activation strain model (ASM‐NEDA) analysis. The proposed chain end control (CEC) model suggests that the ligand framework adopts a chiral configuration mimicking the enantiomorphic site control (ESC) while also incorporating control of the last inserted monomer unit. It is found that the ligand wrapping mode around the aluminium centre is dictated by the monomer configuration (R,R‐LA and S,S‐LA). A good correlation with experimental data is achieved only when accounting for the ligand dynamic features and its steric influences, as highlighted by %VBur steric maps and ASM‐NEDA analysis. Understanding the ESC and CEC interplay is an important target for obtaining stereoselective ROP polymerization for the synthesis of biodegradable materials with tailored properties. [ABSTRACT FROM AUTHOR]

Systematic construction of isoreticular hydrogen‐bonded organic frameworks (HOFs) promises tailored material properties crucial for diverse applications, yet is challenging due to the weak, flexible, and non‐directional nature of hydrogen bonds. Herein, we develop an “integrated monomer synthesis‐framework assembly” (ISA) methodology for constructing a series of isoreticular HOFs. Unlike traditional methods where monomers are first synthesized and then assembled into HOFs, the ISA system employs dicyandiamide rigid hydrogen‐bonded hexameric clusters as connecting nodes to covalently react with planarized C3‐symmetric cyano‐precursors (C3‐CPs) to generate diaminotriazine (DAT) monomers, while simultaneously inducing the directional assembly into isoreticular (6,3)‐net hcb topological DAT‐C6‐HOFs. The pore sizes and microenvironments of the resulting DAT‐C6‐HOFs can be precisely tuned by varying the structural modulation (length and steric hindrance) of the π‐bridge on C3‐CPs, enabling highly selective sensing towards perfluorooctanoic acid over other homologous molecules, that are difficult to be separated and detected by chromatography. Overall, the ISA methodology facilitates the scalable creation of families of isostructural HOFs and provides a customized structural platform for investigating factors beyond topology that impact the capturing, releasing, and responding to guest molecules. [ABSTRACT FROM AUTHOR]

Supramolecular polymers are typical self-assemblies, in which repeating monomer units are bonded together with dynamic and reversible noncovalent interactions. Supramolecular polymers can combine the advantages of polymer science and supramolecular chemistry. Aggregation-induced emission (AIE) means that a molecule remains faintly emissive in the dispersed state but intensively luminescent in a highly aggregated state. AIE has brought new opportunities and further development potential to the field of polymeric chemistry. The integration of AIE luminogens with supramolecular interactions can provide new vitality for supramolecular polymers. Therefore, it is essential for scientists to understand the preparation and applications of AIE-active supramolecular polymers. This review focuses on the recent advanced progress in the preparation of AIE-active supramolecular polymers. In addition, we summarize the newly developed supramolecular polymers with an AIE nature and their applications in chemical sensing, and in vitro and in vivo imaging, as well as the visualization of their structure and properties. Finally, the development trends and challenges of AIE-active supramolecular polymers are prospected. [ABSTRACT FROM AUTHOR]

A photoactive covalent organic framework (COF) was built from metalloporphyrin and bipyridine monomers and single‐atomic Pt sites were subsequently installed. Integrating photosensitizing metalloporphyrin and substrate‐activating Pt(bpy) moieties in a single solid facilitates multielectron transfer and accelerates photocatalytic hydrogen evolution with a maximum production rate of 80.4 mmol h−1 gPt−1 and turnover frequency (TOF) of 15.7 h−1 observed. This work demonstrates that incorporation of single‐atomic metal sites with photoactive COFs greatly enhances photocatalytic activity and provides an effective strategy for the design and construction of novel photocatalysts. [ABSTRACT FROM AUTHOR]

The stereoregularity of poly(lactide) (PLA) plays a significant role in its physicochemical properties. In recent years, various metallic and nonmetallic catalysts have been developed. Organic catalysts, in particular, have garnered attention due to their potential use in biomedical applications, making them safer options. This study presents the design of a cost‐effective thiourea‐based racemic organocatalyst [(rac‐TU)Me] and its effective utilization in ring‐opening polymerization (ROP) of lactide. Using the catalyst and optimized base (N,N‐dimethylcyclohexylamine), ROP in dichloromethane achieved 98% monomer conversion and controlled molecular weights in 48 h. The polylactides obtained using this catalyst exhibited moderate tacticity, with a Pm value ranging from 0.71 to 0.78. The bulk structure of synthesized poly(lactic acid) (PLAs) is extensively studied using DSC, FTIR, and WAXS. The DSC analysis indicated stereoregular PLAs synthesized from rac‐lactide exhibited a higher melting transition than isotactic PLAs. Furthermore, the FTIR and WAXS studies revealed characteristic peaks and patterns typically associated with stereocomplex PLAs. These analytical results confirm the stereocomplex bulk structures of these PLAs synthesized using this organic catalyst [(rac‐TU)Me]. [ABSTRACT FROM AUTHOR]

Mn‐catalyzed hydroarylation polyaddition of 1‐(2‐pyrimidinyl)pyrrole (1a) with aromatic diynes is investigated. The use of commercially available MnBr(CO)5 as a precatalyst under the optimized reaction conditions resulted in a site‐ and regioselective hydroarylation polyaddition, affording the corresponding poly(arylenevinylene)s (PAVs) with excellent vinylene selectivity. The reaction protocol eliminates the production of stoichiometric amounts of byproducts from the monomers. The nonstoichiometric polyaddition of an excess amount of 1a with aromatic diynes is also demonstrated. The 2‐pyrimidinyl substituent promoted the intramolecular transfer of the Mn catalyst walking through the 1a moiety. [ABSTRACT FROM AUTHOR]

One of the questions still remaining regarding emulsion polymerization is the issue of mass transfer versus reaction limitation since, by its nature, emulsion polymerization requires monomer transport across an aqueous phase. This question is brought into focus lately by the growing use of miniemulsion polymerization in which the monomer transport step is much less important. This paper will explore the possible rate of monomer transport via collision and ratio this to the maximum rate of polymerization using the Damkohler analysis formality. Results indicate that systems relying on monomer transport by collision will be almost universally monomer‐transport‐limited, thus exhibiting lower‐than‐expected rates of polymerizations. [ABSTRACT FROM AUTHOR]

The design and synthesis of chiral covalent organic frameworks (COFs) with controlled defect sites are highly desirable but still remain largely unexplored. Herein, we report the synthesis of a defective chiral HD‐TAPB‐DMTP COF by modifying the chiral monomer helicid (HD) into the framework of an achiral imine‐linked TAPB‐DMTP COF using a chiral monomer exchange strategy. Upon the introduction of the chiral HD unit, the obtained defective chiral HD‐TAPB‐DMTP COF not only displays excellent crystallinity, large specific surface area (up to 2338 m2/g) and rich accessible chiral functional sites but also exhibits fluorescence emission, rendering it a good candidate for discrimination of amino acids. Notably, the resultant defective chiral HD‐TAPB‐DMTP COF can be used as a fluorescent sensor for enantioselective recognition of both tyrosine and phenylalanine enantiomers in water, showing enhanced fluorescent responses for the L conformations over those of the D conformations with the enantioselectivity factors being 1.84 and 2.02, respectively. Moreover, molecular docking simulations uncover that stronger binding affinities between chiral HD‐TAPB‐DMTP COF and L‐tyrosine/L‐phenylalanine in comparison to those with D‐tyrosine/D‐phenylalanine play important roles in enantioselective determination. This work provides new insights into the design and construction of highly porous defective chiral COFs for enantioselective fluorescence recognition of amino acids. [ABSTRACT FROM AUTHOR]

This paper presents a detailed physical model for a novel method of two- and three-dimensional microstructure formation: dry electron beam etching of the resist (DEBER). This method is based on the electron-beam induced thermal depolymerization of positive resist, and its advantages include high throughput and relative simplicity compared to other microstructuring techniques. However, the exact mechanism of profile formation in DEBER has been unclear until now, hindering the optimization of this technique for certain applications. The developed model takes into account the major DEBER phenomena: e-beam scattering in resist and substrate, e-beam induced main-chain scissions of resist molecules, thermal depolymerization of resist, monomer diffusion, and resist reflow. Based on the developed model, a simulation algorithm was implemented, which allowed simulation of the profile obtained in resist by DEBER. Experimental verification of the DEBER model was carried out, which demonstrated the reliability of the model and its applicability for theoretical study of this method. The ultimate DEBER characteristics were estimated by simulation. The minimum line width and the maximum profile slope that could be obtained by DEBER were approximately 300 nm and 70°, respectively. [ABSTRACT FROM AUTHOR]

The network structure and reactivity of suitable restoration agent consisting of silane coupling agents (SCAs) of the brittle walls of a cultural heritage site located underground in a desert area in Egypt were investigated using 1H pulsed nuclear magnetic resonance (pulse NMR). It should possess both high coagulation strength and ductility to ensure that it can withstand an earthquake; it should also contain ethoxy rather than methoxy groups, which generate toxic methanol. The solidification rate for the SCA or oligomer with ethoxy groups was lower than those with methoxy groups; however, the final polycondensates showed the same relaxation time (hardness). The difference spectrum was developed newly to analyze the network structure combined higher strength and ductility. The distribution of crosslinking degree of such polycondensates was narrow, and the amount of lower crosslinking degree was small. On the other hand, the distribution was wide in the polycondensates with ductility but lower strength. From the compression tests of model sand solidified with the restoration agent for both methoxy and ethoxy types showed the superior properties combined higher strength and ductility. The pulse NMR experiment was useful for estimating the solidification rate and the network structure. [ABSTRACT FROM AUTHOR]

The development of amphiphiles for sustained drug delivery represents a promising approach in biomedical fields. Polymeric self‐assembly with a hydrophobic core offers plenty of opportunities to encapsulate hydrophobic drugs for facilitating targeted delivery to the specific sites of action. Herein, N‐Boc tryptophan has been used to develop a hydrophobic monomer, Boc‐tryptophan‐HEMA (HBT). The HBT monomer has further been grafted on modified alginic acid through the RAFT technique to synthesize a unique amphiphilic copolymer with fluorescence characteristics. The advanced polymer chromatography demonstrates a narrow distribution curve, signifying the living nature of polymerization. The copolymer has exhibited self‐aggregation behavior with two distinct shapes at two different critical aggregation concentrations (CAC). The concentration‐dependent shape variation has been investigated using FESEM and TEM analyses, further supported by a small‐angle x‐ray scattering analysis. The self‐aggregation behavior of the copolymer facilitates the uptake of a model hydrophobic drug (naproxen) and its release in a sustained manner with varied rates at two different concentrations. [ABSTRACT FROM AUTHOR]

Dental caries is the most widespread form of disease, affecting over 90% of the global population. Amalgam fillings, which have been in use for nearly two centuries, will face an European Union ban by 2025. Although photocomposite fillings are a suitable alternative, health concerns persist because of potential substance release into the oral cavity. This study aimed to evaluate the release of photoinitiator substances and monomers from dental materials into various solvents at different temperatures over 30 days. Cylindrical specimens of the composite resins were submerged in different extraction solutions and incubated at 37 and 50°C. The findings demonstrated that both the extraction solvent and extraction temperature significantly influenced the quantity of leachables (p < 0.05). Furthermore, most leachables were released within the initial days, although some monomers continued to elute for over 30 days. The estimated daily intake was calculated for the worst‐case scenario, confirming the biocompatibility of the composite fillings. The weight loss of dental materials ranged up to 3.5% after 30 days, regardless of the extraction conditions and dental material (p > 0.05). In conclusion, this study contributes to filling several research gaps in the field by addressing the biocompatibility of various dental materials through quantitative and qualitative analyses supported by statistical evaluation. [ABSTRACT FROM AUTHOR]

The introduction of long and flexible polyether chains in epoxy resins is an effective method to improve their toughness. However, using the hydrophilicity/hydrophobicity of polyether chains to tune their moisture resistance has been overlooked currently. In this work, two types of polyether‐based diglycidyl ethers with hydrophilic poly(oxyethylene) (DGEPOE) and relatively hydrophobic poly(oxybutylene) segments (DGEPOB) are synthesized and then binary‐cured with commercial diglycidyl ether of bisphenol A (DGEBA), respectively, yielding the corresponding DGEPOE:DGEBA‐m:ns and DGEPOB:DGEBA‐m:ns based on various ratios. For comparison, pure DGEPOEr, DGEPOBr, and DGEBAr resins are also prepared. Results show that the equilibrium water uptake of DGEPOB:DGEBA‐m:ns is at least less than one‐fifth of that of DGEPOE:DGEBA‐m:ns; meanwhile, the diffusion coefficients of water molecules in DGEPOB:DGEBA‐m:ns are also 1–2 orders of magnitude lower than those in DGEPOE:DGEBA‐m:ns, demonstrating that the incorporation of hydrophobic POB chains can significantly reduce the hygroscopicity of resins. Moreover, DGEPOB:DGEBA‐m:ns not only exhibit superior flexibility and ductility relative to pure DGEBAr, but display exceptional strength and toughness in comparison with pure DGEPOBr. These findings suggest that tuning the hydrophilicity/hydrophobicity of building units of epoxy monomers offers a promising strategy for developing high‐performance epoxy materials, especially suitable for humid environments. [ABSTRACT FROM AUTHOR]

The creation of complex hollow nanostructures with precise control over size and shape represents a great challenge in supramolecular soft materials. Here, we have further developed a bioinspired methodology for the formation of aqueous nanotubes of well‐defined dimensions and pore coating through the self‐assembly of amphiphiles that are chemically programmed with complementary nucleobases. These nanotubes are endowed with a hydrophobic lumen, whose diameter can be expanded as a function of the monomer length, in which apolar dyes can be efficiently encapsulated. [ABSTRACT FROM AUTHOR]

In order to improve the solubility of metallated monomers and product crystallinity, metal–covalent organic frameworks (MCOFs) are commonly prepared via high‐temperature sol‐vothermal synthesis. However, it hampers the direct extraction of crystallization evolution information. Exploring facile room‐temperature strategies for both synthesizing MCOFs and exploiting the crystallinity mechanism is extremely desired. Herein, by a novel single‐phase synthetic strategy, three MCOFs with different microstructure is rapidly prepared based on the Schiff base reaction between planarity‐tunable C3v monomers and metallated monomers at room temperature. Based on detailed time‐dependent experiments and theoretical calculations, it is found that there is a planarity‐tuned and competitive growth relationship between disordered structures and crystal nucleus for the first time. The high planarity of monomers boosts the formation of crystal nucleus and rapid growth, suppressing the forming of amorphous structures. In addition, the microenvironment effect on selective photocatalytic coupling of benzylamine (BA) is investigated. The strong donor‐acceptor (D‐A) MCOF exhibits efficient photocatalytic activity with a high conversion rate of 99% and high selectivity of 99% in 5 h under the 520 nm light irradiation. This work opens a new pathway to scalable and efficient synthesis of highly crystalline MCOFs. [ABSTRACT FROM AUTHOR]

The reaction center-light-harvesting complex 1 (RC-LH1) plays an essential role in the primary reactions of bacterial photosynthesis. Here, we present high-resolution structures of native monomeric and dimeric RC-LH1 supercomplexes from Rhodobacter (Rba.) blasticus using cryo-electron microscopy. The RC-LH1 monomer is composed of an RC encircled by an open LH1 ring comprising 15 aß heterodimers and a PufX transmembrane polypeptide. In the RC-LH1 dimer, two crossing PufX polypeptides mediate dimerization. Unlike Rhodabacter sphaeroides counterpart, Rba. blasticus RC-LH1 dimer has a less bent conformation, lacks the PufY subunit near the LH1 opening, and includes two extra LH1 aß subunits, forming a more enclosed S-shaped LH1 ring. Spectroscopic assays reveal that these unique structural features are accompanied by changes in the kinetics of quinone/quinol trafficking between RC-LH1 and cytochrome bc1. Our findings reveal the assembly principles and structural variability of photosynthetic RC-LH1 supercomplexes, highlighting diverse strategies used by phototrophic bacteria to optimize light-harvesting and electron transfer in competitive environments. [ABSTRACT FROM AUTHOR]

α-Synuclein (α-syn), a crucial molecule in Parkinson's disease (PD), is known for its interaction with lipid membranes, which facilitates vesicle trafficking and modulates its pathological aggregation. Deciphering the complexity of the membrane-binding behavior of α-syn is crucial to understand its functions and the pathology of PD. Here, we used single-molecule imaging to show that α-syn forms multimers on lipid membranes with huge intermultimer distances. The multimers are characterized by self-limiting growth, manifesting in concentration-dependent exchanges of monomers, which are fast at micromolar concentrations and almost stop at nanomolar concentrations. We further uncovered movement patterns of α-syn's occasional trapping on membranes, which may be attributed to sparse lipid packing defects. Mutations such as E46K and E35K may disrupt the limit on the growth, resulting in larger multimers and accelerated amyloid fibril formation. This work emphasizes sophisticated regulation of α-syn multimerization on membranes as a critical underlying factor in the PD pathology. [ABSTRACT FROM AUTHOR]

Recently, the important role of sterically bulky aromatic substituents at the axial position of the metal center for synthesizing high‐performance catalysts were recognized. In this study, a series of α‐diimine nickel complexes with bulky N‐ortho‐aryl substituents were designed and synthesized. The as‐synthesized nickel complexes showed high activities (up to 2.3×107 g ⋅ mol−1 ⋅ h−1) and superior thermostability, giving access to moderately branched polyethylenes (35–86/1000 C) with high molecular weights (up to 197.5×104 g ⋅ mol−1). The polyethylene materials generated by these nickel complexes at 80 °C exhibited outstanding tensile mechanical. In addition, these nickel complexes could also catalyze the copolymerization of ethylene and polar monomer with modest activity (such as undecenoic acid, 10‐undecen‐1‐ol and 6‐chlorohex‐1‐ene), yielding functionalized polyolefin with adjustable molecular weights (6.8–222.9×104 g ⋅ mol−1) and incorporation ratios (0.2–4.3 mol %). [ABSTRACT FROM AUTHOR]

In the realm of biological macromolecules, entities such as nucleic acids and proteins are distinguished by their homochirality, consistently defined chain lengths, and integral sequence‐dependent functionalities. Historically, these refined attributes have eluded traditional synthetic polymers, which often exhibit wide variabilities in chain lengths, limited batch‐to‐batch reproducibility, and stochastic monomer arrangements. Bridging this divide represents a pivotal challenge within the domain of polymer science – a challenge that the burgeoning discipline of precision polymer chemistry is poised to address. Recent advancements have yielded precision polymers that boast prescribed monomer sequences and narrow molecular weight distributions, heralding a new era for developing model systems to decipher structure‐property correlations within functional polymers, analogous to those within biological matrices. This review discusses the innovative liquid‐phase and solid‐phase synthesis techniques for creating precision polymers and the advanced characterization tools essential for dissecting their structure and properties. We highlight potential applications in self‐assembly, catalysis, data storage, imaging, and therapy, and provide insights into the future challenges and directions of precision polymers. [ABSTRACT FROM AUTHOR]

The production of Li2CO3/C through CO2 reduction reaction in nonaqueous systems is a complex four‐electron, multi‐step process, and the short existence time of intermediate monomers is not conducive to observation, which causes great difficulties in clarifying and regulating the CO2 reduction path. Herein, ferrocene (Fc) as a functional additive into the electrolyte can stabilize the discharge intermediates and favor the occurrence of the two‐electron reaction path during CO2RR, which leads to more stable operation of the Li‐CO2 battery; with the assistance of Fc, the CO2 reduction pathway in Li‐CO2 battery is also clarified. Theoretical calculation analysis combined with experimental characterization observation confirms that Fc can shorten the CO2 reduction distance through interaction with CO2 and affecting the solvent environment around Li+, stabilize intermediate products to clarify the discharge path. The existence time of intermediates and discharge depth of the battery are key factors affecting the CO2 reduction pathway. The Li2C2O4 formed by CO2 reduction through the 2‐electron pathway is more favorable for the reversible operation of the Li‐CO2 battery than Li2CO3/C through the 4‐electron pathway. This work provides inspiration for clarifying the reaction mechanism and regulating the CO2 reduction pathway to improve the electrochemical performance of Li‐CO2 battery in the future. [ABSTRACT FROM AUTHOR]

Rose bengal (RB) is a widely used photosensitizer for determining quantum yields of singlet oxygen generation. While it is known to aggregate in polar environments at concentrations above 2 μM, the relationship between RB concentration and singlet oxygen photogeneration remains unclear. This study investigates the shift from monomeric to dimeric RB with increasing concentration and its impact on singlet oxygen generation in D2O‐based solutions and DMPC liposomes. Absorbance maxima for RB were observed at 514 nm (dimer) and 549 nm (monomer), with ionic environments influencing aggregation rates. Singlet oxygen phosphorescence showed non‐linear dependency above 2 μM, indicating the effects of aggregation. Results suggest that RB concentrations should be kept at 1 μM or lower in photochemical studies to avoid aggregation‐related discrepancies in singlet oxygen yield determination. These findings highlight the importance of considering RB aggregation in photochemical research and medical applications. [ABSTRACT FROM AUTHOR]

Photocatalytic technology has been widely studied, discussed, and tested as a feasible wastewater degradation technology. The present study demonstrated the preparation of g‐C3N4 material using solid‐state sintering method and the construction of Bi4Ti3O12/g‐C3N4 heterostructure via hydrothermal method. This direct contact Z‐type heterojunction improves the wide bandgap of Bi4Ti3O12 monomer, enhances its photoresponsiveness, and thus improves its photocatalytic performance. During the process of photocatalytic experiments, an environment of cold and hot fluctuations were created, and the pyroelectric effect was utilized to induce self‐polarization of the material and formed an internal electric field. It improves the transport ability of electron–hole pairs and suppresses their recombination in the transport path. According to the degradation experiment results, the degradation efficiency of pyroelectric synergistic heterojunction photocatalysis reached 88.7%, which was 2.27 times that of Bi4Ti3O12. It proves that the photocatalysis by pyroelectric synergistic heterojunction has good application prospects. [ABSTRACT FROM AUTHOR]

Existing adsorption materials with drawbacks in the weak organic solvents/oil retention ability, slow adsorption speed and low adsorption capacity for alkanes still hardly meet demands of the application field, especially in emergencies. The copolymerization of the long‐chain alkenes, 1‐octene, with isoprene was designed in this paper to synthesize an adsorption resin (PIOT), instead of acrylate monomers reported in the literature. And trimethylolpropane triacrylate was designed as a crosslinking agent. Results show that the PIOT grows in the form of powders, which are the loose accumulation of nanoflakes with a diameter of about 47.89 ± 11.06 nm. In view of the chain structure and morphology of the PIOT, it can quickly reach the maximum adsorption within 10 s along with a high adsorption capacity for various solvents and kerosene. Even for hexane, the adsorption capacity of the PIOT increases by 345.2% compared with the reported adsorption resin. The oil retention rate of PIOT can be maintained at 86 ± 6% after centrifugation at 1000–3000 rpm for 5–25 min. Compared with commercial activated carbon, the PIOT has outstanding advantages in recycling property and oil retention rate and compared with the reported acrylate adsorption resin, the PIOT has made a great breakthrough in adsorption capacity for alkanes. [ABSTRACT FROM AUTHOR]

Polyvinyl chloride (PVC) is the world's third-most widely manufactured thermoplastic, but has the lowest recycling rate. The development of PVC-like plastics that can be depolymerized back to monomer contributes to a circular plastic economy, but has not been accessed. Here, we develop a series of chemically recyclable plastics from the reversible copolymerization of cyclic anhydride with chloral. The copolymerization is highly efficient through the anionic or cationic mechanism under mild conditions, yielding polyesters with tunable structure and properties from multiple commercial monomers. Notably, these polyesters manifest mechanical properties comparable to PVC and polystyrene. Meanwhile, such polyesters are flame-retardant like PVC due to high chloride content. Of significance, these polyesters can be depolymerized back to starting monomers at high temperatures owing to the reversibility of the copolymerization, leading to a circular economy. Overall, the readily available monomers, simple synthesis, advantageous performance, and practical recyclability make the polymers promising for applications. The development of PVC-like plastics that can be depolymerized back to monomer contributes to a circular plastic economy but remains understudied. Here, the authors develop a series of chemically recyclable plastics from the reversible copolymerization of cyclic anhydride with chloral. [ABSTRACT FROM AUTHOR]

Incorporating photoswitchable moieties into the molecular design of supramolecular architectures provides unique opportunities for controlling their morphology and functionality via optical stimuli. Harnessing geometrical and electrical changes in response to multiple external stimuli on the molecular level to modulate properties remains a fundamental challenge. Herein, the reversible formation of the aggregates of l‐tyrosine E‐azobenzene‐tetracarboxamide (E‐ABT) is shown to be finely controlled by light, solvent, or chemical additives. The resulting products differ not only in their overall morphology and supramolecular interactions, but also in their intrinsic chirality, that is, depending on the conditions applied, self‐assembly yields chiral columns or π‐stacked "achiral" oligomers. This report shows the potential of rational monomer design to achieve controlled self‐assembly by stimuli of choice and paves the way toward the use of multi‐responsive, sterically hindered azo‐benzene aggregates in materials chemistry and nanotechnology. [ABSTRACT FROM AUTHOR]

Alginate is a brown seaweed-based linear polysaccharide of D – mannuronic acid and L – guluronic acid residues. Hydrolysis products of the polysaccharide, specifically oligosaccharides, have been receiving increasing interest, due to their significant bioactivity and potential utilisation routes. The bioactivity of alginate oligosaccharides is closely linked to structural characteristics, namely: molecular weight, degree of polymerisation, and ratio of the monomers (the M/G ratio). Hence, potential applications (such as utilisation as a biostimulant fertilizer) depend on these parameters. This review focuses on recent advances in producing alginate oligosaccharides using chemical or enzymatic methods. The literature survey includes utilisation of these methods at both laboratory and industrial scale. For the chemical methods, we assessed the standard laboratory scale procedures of alginate oligosaccharide production, the potential of scaling up to an industrial level, and the subsequent challenges. For the enzymatic route, we provide an overview of alginate lyases and the application perspectives of enzymatic hydrolysis of alginate. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) was produced by exfoliating natural flake graphite using Hummers' method. Using the ionic liquid 1-allyl-3-methyl-imidazolium chloride (AMICl), the surface characteristics of the GO sheets were carefully altered to form nanocomposites containing ethylene-propylene-diene monomer (EPDM), styrene-butadiene rubber (SBR), and functionalized GO (GO-IL). The research showcases the incorporation of a reinforcing filler, GO-IL, as opposed to GO alone, leading to significant improvements in both the mechanical properties and swelling resistance of 80/20 EPDM/SBR blend nanocomposites. The distinctive amphiphilic nature of GO-IL facilitated its interaction with EPDM/SBR, thereby substantially enhancing the mechanical properties and swelling resistance of the composite system. With incorporation of only 6 phr GO-IL, the tensile strength and stress at 100% elongation of EPDM/SBR blend increased by 257% and 135%, respectively. This study indicates that GO-IL holds promise as a viable reinforcing filler for EPDM/SBR blends. [ABSTRACT FROM AUTHOR]

Polymeric derivatives of poly-N-vinylpyrrolidone containing different amounts of linker carboxylate ligands (partially hydrolyzed poly-N-vinylpyrrolidone with 5 mol% COOH groups and copolymers of N-vinylpyrrolidone with other monomers) were synthesized. The following copolymers were obtained: N-vinylpyrrolidone/crotonic acid and N-vinylpyrrolidone/N-vinylamidoanthanoic acid (containing 16 and 50 mol% COOH-groups). Metal-polymer complexes (MPC) with varying europium content were prepared through the interaction of the obtained polymers with equimolar amounts of hydroxocomplex Eu(Phen)2(OH)3 (Phen = 1,10-phenanthroline). The polymers and MPC were characterized by elemental analysis, IR, UV-vis spectroscopy and photoluminescence; their cytotoxicity toward living cells was estimated. All the obtained MPC exhibited photoluminescence with higher intensity than that of the reference complex Eu(Phen)2Br3. The dependence of luminescence intensity on the content of metallocenters in MPC was demonstrated. The relative quantum yield of luminescence was found to decrease with increasing europium content in MPC. It was shown that none of the polymers under investigation exhibited cytotoxicity. Furthermore, the presence of the polymeric anion in MPC contributed to a sharp decrease in the toxicity of metallocenter [Eu(Phen)2]3+solv. The MPC based on the N-vinylpyrrolidone/N-vinylamidoanthanoic acid copolymer exhibited no cytotoxicity within the entire investigated concentration range. [ABSTRACT FROM AUTHOR]

The preparation of three metal (Ag(I) and Hg(II)) complexes based on bis‐carbene ligands and correlative three precursors H2Ln·(PF6)2 (n = 1–3) were reported. In each cationic moiety of complexes 1 and 2 and the monomer of complex 3, two Ag+ (or Hg2+) ions and two Ln (n = 1–3) formed one 36‐membered macrometallocycle. There existed π–π interactions between two naphthalenes in each cationic moiety of 1 and 2. The monomers of 3 were connected together through HgO bonds to form 1D chain. In the crystal packings of 1–3, two‐dimensional and three‐dimensional supramolecular structures were formed through CH˙˙˙π contacts and CH˙˙˙F H bonds. Additionally, the recognition capacity of 1 for H2PO4− was studied via fluorescence spectra, UV/Vis spectra, HRMS, 1H NMR titrations, and infrared (IR) spectra. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) have been widely studied due to their versatile applications and easily tunable structures. However, heteroatom‐metal coordination dominates the MOFs community, and the rational synthesis of carbon–metal coordination‐based MOFs remains a significant challenge. Herein, two‐dimensional (2D) MOFs based on silver–carbon linkages are synthesized through the coordination between silver(I) salt and isocyanide‐based monomers at ambient condition. The as‐synthesized 2D MOFs possess well‐defined crystalline structures and a staggered AB stacking mode. Most interestingly, these 2D MOFs, without π–π stacking between layers, exhibit narrow band gaps down to 1.42 eV. As electrochemical catalysts for converting CO2 to CO, such 2D MOFs demonstrate Faradaic efficiency over 92 %. Surprisingly, the CO2 reduction catalyzed by these MOFs indicates favorable adsorption of CO2 and *COOH on the active carbon sites of the isocyanide groups rather than on silver sites. This is attributed to the critical σ donor role of isocyanides and the corresponding ligand‐to‐metal charge–transfer effect. This work not only paves the way toward a new family of MOFs based on metal–isocyanide coordination but also offers a rare platform for understanding the electrocatalysis processes on strongly polarized carbon species. [ABSTRACT FROM AUTHOR]