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In this work, we present a multiscale real-time approach to study the plasmonic effects of a metal nanoparticle (NP) on the electronic circular-dichroism (ECD) spectrum of a chiral molecule interacting with it. The method is based on the time-evolution of the molecule's time-dependent wavefunction, expanded in the eigenstates of a perturbed Hamiltonian. A quantum description of the molecular system is coupled to a classical representation of the NP via a continuum model. The method is applied to methyloxirane and peridinin at various distances (1, 3, and 5 nm) with respect to a gold NP surface. While no remarkable effect is observed for methyloxirane at any studied distance, an enhancement appears when the peridinin lies at 1 nm and the pulse is linearly polarized perpendicularly to the molecular axis, with the ECD signal centered at 4.1 eV increased by a factor of around 20. These results are rationalized looking at the gap between the plasmonic peak of the NP at around 2.5 eV and the molecular excitations: the smaller the gap between molecular and plasmonic excitations, the larger the plasmonic enhancement of the ECD signal. Moreover, ECD peaks are selectively enhanced due to the favorable coupling between the pulse polarization and the combined effect of electric and magnetic dipole moments. This approach allows one to go through the electronic structure and dynamics of chiral molecules for obtaining a realistic description of plasmon-mediated ECD spectra, e.g., paving the way to applications to molecules of biological relevance interacting with nanostructures of experimental interest. [ABSTRACT FROM AUTHOR]

The segmental dynamics of bottlebrush polymers with a stiff backbone and flexible side chains has been studied. The segmental relaxation time of side chains attached to a flexible backbone follows the same trend as linear polymers, an increase with the increasing molecular weight, but is slowed down compared to their linear counterparts. Theoretical work predicts a reversal of the molecular weight dependence of the relaxation time for stiff backbones. As a model for a stiff-g-flexible system, bottlebrushes with poly(norbornene) backbone and poly(propylene oxide) side chains, PNB-g-PPO, at a uniform grafting density have been synthesized and characterized with quasi-elastic neutron scattering. Indeed, the anticipated reversed dynamics was found. Increasing the side chain length decreases the segmental relaxation time. This indicates the importance of the characteristics of the grafting site beyond a simplified picture of an attached side chain. The mean square displacement shows a similar trend with longer side chains exhibiting a larger displacement. [ABSTRACT FROM AUTHOR]

Nb-Sn, V-Sn mixed-metal oxides and Nb-Si, V-Si metal oxide–silicas were successfully synthesized through a "soft" templating method, in which appropriate amounts of metal salts (either niobium(V) chloride, or vanadium(IV) oxide sulfate hydrate or tin(II) chloride dihydrate) or tetraethyl orthosilicate (TEOS) were mixed with hexadecyltrimethylammonium chloride (HDTA) or sodium dodecyl sulfate (SDS) solutions to obtain a new series of mesoporous oxides, followed by calcination at different temperatures. As-obtained samples were characterized by SEM, TEM, XRD, and UV-Vis spectra techniques. The photocatalytic activities of the samples were evaluated by degradation of methyl orange II (MO) under simulated sunlight irradiation. The effects of metal species and calcination temperature on the physicochemical characteristic and photocatalytic activity of the samples were investigated in detail. The results indicated that, compared to pure oxides, mixed-metal oxide showed superior photocatalytic performance for the degradation of MO. A maximum photocatalytic discoloration rate of 97.3% (with MO initial concentration of 0.6·10−4 mol/dm3) was achieved in 300 min with the NbSiOx material, which was much higher than that of Degussa P25 under the same conditions. Additionally, the samples were tested in the photochemical oxidation process, i.e., advanced oxidation processes (AOPs) to treat the commercial non-ionic surfactant: propylene oxide ethylene oxide polymer mono(nonylphenyl) ether (N8P7, PCC Rokita). A maximum of 99.9% photochemical degradation was achieved in 30 min with the NbSiOx material. [ABSTRACT FROM AUTHOR]

Propylene liquid-phase epoxidation with 50–75% H 2 O 2 is an important process for the industrial production of propylene oxide (PO). To realize a propylene epoxidation process that proceeds with low hydrogen peroxide concentration, we developed an integrated Mn/TS-1/N catalytic system via in-situ reaction of Mn/TS-1 with an N-donor ligand, affording the PO product in excellent yield with only 30 wt% H 2 O 2. Other long-chain aliphatic epoxides were also readily synthesized by this catalytic epoxidation system. Moreover, in addition to the standard micro-pressure reactor, a continuous-flow microreactor was developed that executed the hydrogen peroxide propylene oxide (HPPO) process with excellent efficiency for 1300 hours. This innovative Mn/TS-1/N catalyzed epoxidation represents a promising direction for advancing HPPO industrial processes, offering improved efficiency while minimizing the reliance on high concentrations of H 2 O 2. [ABSTRACT FROM AUTHOR]

Rubber tires are fundamental components of modern society and industrial operations, holding an irreplaceable position in the global manufacturing and transportation sectors. The potential for traditional rubber tires to enhance performance is gradually approaching its limits, rendering it challenging to further improve low rolling resistance, high wet-skid resistance, and high wear resistance (called "magic triangle"). Moreover, the reliance on petroleum resources for rubber hinders the sustainable development of rubber tires. In this work, a series of novel polyurethane (PU) elastomers with potential applications in high-performance automotive tires were synthesized by CO2-based poly(propylene carbonate) diol and bio-based poly(propylene oxide) glycol (PO3G). The comprehensive influences of PO3G on the thermal, mechanical, rolling resistance, and wear properties of the elastomers were systematically investigated. The results illustrated that increasing the PO3G content significantly enhanced the wear resistance by 98.43% and the wet-skid resistance by 73.21% and reduced the rolling resistance by 15.38% of the elastomers compared to commercial green tires (HT166). The rational design strategy of PU elastomers not only effectively addresses the "magic triangle" challenge in the tire industry but leverages CO2 to contribute to the sustainable development of the automotive sector. [ABSTRACT FROM AUTHOR]

Diethyl carbonate (DEC) was synthesized through catalytic conversion from carbon dioxide (CO2) and ethanol. However, common challenges in synthesizing DEC from CO2 have been high energy consumption, catalysts-dehydrating agent selection, and relatively complex reaction. In this study, propylene oxide (PO) was used as a dehydrating agent, and KI/Sodium ethoxide was employed as a catalyst, resulting in the highest yield of DEC. The synthesis was conducted in a stainless steel reactor under batch conditions, with an initial CO2 pressure ranging from 20 to 40 bar, a reaction temperature between 130-190°C, and a reaction time of 1-5 hours. Product identification was conducted with gas chromatography analysis with FID detector. Besides kinetic study, optimizing the parameter process in DEC synthesis is necessary to find the highest yield of DEC because it is difficult to achieve optimum conditions using trial and error. So, this parameter process synthesis was also optimized with the Box-Bhenken Design (BBD) method to get optimal conditions and an equation to predict the yield of DEC. As confirmed with the BBD method, an initial pressure of CO2 40 bar, 190°C, and a 3-hour reaction were expected to perform optimized processing. By applying these optimized process parameters in experimental work, a DEC yield of up to 24.07% was obtained. This experimental result was relatively consistent with the findings of the simulation study, which achieved a yield of 24.3%. [ABSTRACT FROM AUTHOR]

This paper reports on the association between urine concentrations of Volatile Organic Compounds (UVOCs) metabolites and Cardiovascular Diseases (CVDs). This cross-sectional study uses a sample of participants from the NHANES (2017–2020). We assessed the dose association of UVOCs with CVD by running multivariable logistic regression models at the second, third and fourth quartiles. Among 2,363 participants in the National Health and Nutrition Examination Survey (NHANES) who had complete UVOC and CVD disease data, 11.9% (N = 282) had at least one cardiovascular disease event. The UVOCs of Acrolein (aOR 2.26, 95%CI 1.24–4.12 p = 0.01), Acrylamide (aOR 1.81, 95%CI 1.20–2.73, p = 0.006), 1,3-Butadiene (aOR 2.06 95%CI 1.13–3.75, p = 0.019), Propylene oxide (2.12, 95%CI 1.22–3.70, p = 0.01) in quartile-4 were associated with higher odds of CVDs. At high concentrations, metabolites of Benzene, Acrolein, Acrylonitrile, 1,3-Butadiene, and Crotonaldehyde increase the odds of developing stroke. [ABSTRACT FROM AUTHOR]

Despite extensive research into developing efficient and environmentally friendly catalysts for converting CO2 over the last decade, the search for a robust and cost‐effective catalytic system is ongoing. This study describes developing and applying a new catalytic system using inexpensive ferrate and zincate anions immobilized on easily available commercial ion exchange resins (IER) to produce cyclic carbonates from CO2 with high efficiency and low cost. Two polystyrene‐based anion exchange resins, AmberlystTM A26‐Cl (A26‐Cl) and AmberliteTM IRA‐400‐Cl (IRA400‐Cl), were compared. The results demonstrated the catalysts' remarkable activity under mild conditions and demonstrated the synergistic effect between the polystyrene support and the active ammonium metallates, presenting a scalable, eco‐friendly method for cyclic carbonate production using waste CO2. A Design of Experiment (DoE) approach was implemented to optimize the catalytic cycloaddition of CO2. The reaction scale‐up to produce a 5 g batch of propylene oxide and conducting recycling tests demonstrated that the catalyst retained its activity over four cycles. The research also explored the use of various epoxides and found that terminal epoxides produced very good yields. In summary, this study introduces a cost‐effective, scalable method for converting CO2 into valuable cyclic carbonates, leveraging the synergistic effects of polystyrene supports and active ammonium metallates. [ABSTRACT FROM AUTHOR]

Despite extensive research into developing efficient and environmentally friendly catalysts for converting CO2 over the last decade, the search for a robust and cost‐effective catalytic system is ongoing. This study describes developing and applying a new catalytic system using inexpensive ferrate and zincate anions immobilized on easily available commercial ion exchange resins (IER) to produce cyclic carbonates from CO2 with high efficiency and low cost. Two polystyrene‐based anion exchange resins, AmberlystTM A26‐Cl (A26‐Cl) and AmberliteTM IRA‐400‐Cl (IRA400‐Cl), were compared. The results demonstrated the catalysts' remarkable activity under mild conditions and demonstrated the synergistic effect between the polystyrene support and the active ammonium metallates, presenting a scalable, eco‐friendly method for cyclic carbonate production using waste CO2. A Design of Experiment (DoE) approach was implemented to optimize the catalytic cycloaddition of CO2. The reaction scale‐up to produce a 5 g batch of propylene oxide and conducting recycling tests demonstrated that the catalyst retained its activity over four cycles. The research also explored the use of various epoxides and found that terminal epoxides produced very good yields. In summary, this study introduces a cost‐effective, scalable method for converting CO2 into valuable cyclic carbonates, leveraging the synergistic effects of polystyrene supports and active ammonium metallates. [ABSTRACT FROM AUTHOR]

AbstractTo improve the shape recovery degree, the chemical cross-linking mode effectively prevents slippage between molecular chains of shape memory polyurethanes (SMPUs). However, the irregular crosslinked network structure formed tends to be unevenly stressed when subjected to external forces, and stress concentrations occur, leading to a decrease in the mechanical properties of the polymer. To obtain better shape memory properties and mechanical properties, we introduced a four-armed, regularized structure of the pentaerythritol propylene oxide (PO-PTOL) into the SMPUs networks to prepare shape memory polyurethanes (PUX) with the model networks, and controlled the topology of the PUX network by adjusting the content of the PO-PTOL. Among them, PU0.15 exhibited ultra-high mechanical properties (tensile strength, elongation at break, and Young’s modulus of 32 MPa, 2011.7%, and 1.59 MPa, respectively) and excellent shape memory properties (shape recovery time of less than 1 s, shape fixation degree, and shape recovery degree of 92.7% and 98.5%, respectively). This study provides new ideas for designing network structures for SMPUs and is a new paradigm for introducing modeled structures into SMPU networks. [ABSTRACT FROM AUTHOR]

In this paper, macroporous high‐entropy spinel oxide (HESO) (Fe0.2Ni0.2Co0.2Mn0.2Zn0.2)3O4 monoliths were successfully fabricated via a sol–gel method followed by calcination. Appropriate polyacrylic acid and propylene oxide contents allow the formation of three‐dimensional co‐continuous xerogel monoliths, and the water/glycerol ratio controls the macropore size of monoliths. Subsequent calcination achieves the precipitation of HESO (Fe0.2Ni0.2Co0.2Mn0.2Zn0.2)3O4 with a singular phase and exceptional structural stability. The macroporous HESO (Fe0.2Ni0.2Co0.2Mn0.2Zn0.2)3O4 demonstrates remarkable performance in the oxygen evolution reaction (OER) with an overpotential of 333 mV at 100 mA cm−2 and a Tafel slope of 43.2 mV dec–1, surpassing that of RuO2 (391 mV) under identical conditions. Furthermore, the catalytic stability of the HESO catalyst remains superior even after 24 h of testing. This process offers a promising avenue for the development of macroporous high‐entropy oxide OER catalysts for overall water splitting. [ABSTRACT FROM AUTHOR]

Glycerol Carbonate (GC) production via carbonylation of glycerol with CO2 reaction takes attention to its properties of enabling both the utilization of biodiesel by-product glycerol and the use of major greenhouse gas CO2. Herein, the synthesis of GC via glycerol carbonylation with CO2 over a series of ZIF-8 on nickel-loaded Alumina Aerogel catalysts was examined for the first time in literature. ZIF-8 growth on nickel-impregnated Alumina aerogel was executed using an in situ method. Synthesized catalysts were analyzed using SEM–EDX, FT-IR, DRIFTS, XRD, and N2 sorption techniques. The carbonylation reaction of glycerol was conducted in the presence of a co-reactant (propylene oxide) and solvent (methanol). The influence of reaction parameters (temperature, catalyst loading, glycerol/co-reactant molar ratio, co-reactant type, catalyst type, and reaction time) on the catalytic activity (glycerol conversion, GC selectivity and yield) of the catalysts were investigated. It obtained high glycerol conversion (73%) for AA-2Ni-5ZIF, yield (31%), and selectivity (77%) of GC for AA-5Ni-15ZIF under optimized reaction conditions (150 °C, 7 bar, 2 h, 6% catalyst loading and 0.5 glycerol/propylene oxide). Compared to the literature, this activity was found under lower CO2 pressure and reaction time. Unique features of catalysts such as suitable acidity, high surface area, more than one active crystal, and the presence of propylene oxide as a co-reactant promoted the rise of glycerol conversion, GC selectivity, and yield. [ABSTRACT FROM AUTHOR]

The thermoresponsive properties of poloxamine (tetra-branch PEO-PPO block copolymer) hydrogels are related to several variables. Of particular interest to this study were the molecular weight of the polymer, the molar ratio between PEO and PPO blocks, and the concentration of the aqueous solution. Accurately controlling the thermoresponsive behaviors of the polymer is critical to the application of such materials; therefore, the structure–property relationship of tetra-branch PEO-PPO block copolymer was studied by synthesis via anionic ring-opening polymerization (AROP). The structure–property relationships were studied by measuring the thermoresponsive behavior via differential scanning calorimetry (DSC) and developing an empirical model which statistically fit the collected data. This empirical model was then used for designing poloxamines that have critical micellization temperatures (CMT) between room temperature and physiological temperature. The model was validated with three polymers that targeted a CMT of 308 K (35°C). The empirical model showed great success in guiding the synthesis of poloxamines showing a temperature difference of less than 3 K between the predicted and the observed CMTs. This study showed a great potential of using an empirical model to set synthesis parameters to control the properties of the polymer products. [ABSTRACT FROM AUTHOR]

Organocatalysis has shown special potency for simplifying the construction of complex polymer structures. We are reporting here a one-pot synthetic pathway using amine as a selectivity-switching agent in the two-component catalytic system consisting of triethylborane (Et3B) and a phosphazene base. We first modelled the interactions of a variety of amines with Et3B by density functional theory calculations. The results indicate that the aliphatic diamines comprising both primary and tertiary amino groups, capable of forming stable intramolecular hydrogen bonds, undergo the strongest complexation with Et3B. Accordingly, experimental results demonstrate that the addition of such amines promptly actuates the in situ selectivity switch from Lewis pair-catalyzed ring-opening polymerization (ROP) of epoxide (propylene oxide, n-butylglycidyl ether, or glycidyl phenyl ether) to organobase-catalyzed ROP of δ-valerolactone, allowing one-pot continuous synthesis of ether-ester type block copolymers. We thus exploited the noncovalent interaction between amine and Et3B to refine the catalyst switch strategy by exempting it from loading of extra catalyst. [ABSTRACT FROM AUTHOR]

The anti‐emulsification property of lubricating oil is an important index to measure the quality of oil. In this paper, the behaviour of surfactants such as lubricating oil additives at the oil–water interface and the influence of the position of ethylene oxide (EO) and propylene oxide (PO) in the block polyether demulsifier on the demulsification effect were investigated by molecular simulation and experimental verification. The properties of seven lubricating oil additives with different functions and two pairs of isomers were investigated by molecular simulation, and their demulsification effects were verified by experiments. Some simulation results such as interface thickness and density distribution can accurately predict the experimental demulsification effect. Moreover, it was found that the position isomerism of surfactants affected the demulsification performance by changing the lipophilic balance and interface properties. The demulsification performance of sequenced copolymers is generally better than that of anti‐sequenced copolymers. The accurate prediction of molecular dynamics simulation makes the selection of lubricating oil demulsifier more extensive and has practical application value. [ABSTRACT FROM AUTHOR]

Zinc glutarate (ZnGA) is used as a solid-state heterogeneous catalyst for the synthesis of aliphatic polycarbonate from the alternating copolymerization of CO2 and epoxide. However, the conventional synthesis of ZnGA involves the use of a large amount of toluene, which is a toxic substance. In the present study, we developed a solvent-free, environmentally friendly synthesis for ZnGA using a mechanochemical process. This accelerated the formation of flake-like ZnGA microcrystals in a shorter reaction time than that of the conventional method. X-ray diffraction, X-ray photoelectron spectroscopy, X-ray absorption fine structure analyses, and Fourier-transform infrared spectroscopy revealed that ZnO is the most effective source of Zn. This catalyst selectively produced poly(propylene carbonate) from CO2 and propylene oxide, with a molecular weight (M n) of 25,000 and a molecular weight distribution (M w/ M n) of 5.27. We believe that this mechanochemical synthesis is a sustainable alternative to conventional approaches. [ABSTRACT FROM AUTHOR]

Biofilms are a well-known multifactorial virulence factor with a pivotal role in chronic bacterial infections. Their pathogenicity is determined by the combination of strain-specific mechanisms of virulence and the biofilm extracellular matrix (ECM) protecting the bacteria from the host immune defense and the action of antibacterials. The successful antibiofilm agents should combine antibacterial activity and good biocompatibility with the capacity to penetrate through the ECM. The objective of the study is the elaboration of biofilm-ECM-destructive drug delivery systems: mixed polymeric micelles (MPMs) based on a cationic poly(2-(dimethylamino)ethyl methacrylate)-b-poly(ε-caprolactone)-b-poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA35-b-PCL70-b-PDMAEMA35) and a non-ionic poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) (PEO100-b-PPO65-b-PEO100) triblock copolymers, loaded with ciprofloxacin or azithromycin. The MPMs were applied on 24 h pre-formed biofilms of Escherichia coli and Pseudomonas aeruginosa (laboratory strains and clinical isolates). The results showed that the MPMs were able to destruct the biofilms, and the viability experiments supported drug delivery. The biofilm response to the MPMs loaded with the two antibiotics revealed two distinct patterns of action. These were registered on the level of both bacterial cell-structural alterations (demonstrated by scanning electron microscopy) and the interaction with host tissues (ex vivo biofilm infection model on skin samples with tests on nitric oxide and interleukin (IL)-17A production). [ABSTRACT FROM AUTHOR]

The development of green route for preparing propylene oxide (PO) with molecular oxygen is of significance both in academic and industrial. In this work, propylene epoxidation coupled with furfural oxidation catalyzed by platinum meso-tetraphenylporphyrin (Pt (II)TPP) has been developed. Propylene conversion and PO selectivity reached up to 56% and 83%, respectively. Meanwhile, furfural was almost completely converted to furoic acid. Based on operando characterizations and electron paramagnetic resonance (EPR) tests, a mechanism involved high-valent Pt species was proposed. This work is expected to provide a potential application prospects for producing PO and furoic acid simultaneously in chemical industry. [ABSTRACT FROM AUTHOR]

An electrochemical–thermal tandem reaction system was designed in this work and enabled the highly efficient synthesis of propylene oxide (PO) at 1 atm without the use of H2O2. The electrochemical part produced OOH− through a 2e− oxygen reduction reaction, which migrated and distributed in the full space of a chamber filled with a mixture of solid electrolyte particles and modified TS-1 (m-TS-1) catalysts. Mediated by the relay of OOH− and protic solvent methanol, full space tandem reactions were achieved with a high PO selectivity of 95.2% and a productivity of 319.75 mmol gecat−1 h−1. A mechanistic study revealed that the m-TS-1 catalysts accepted the migrated OOH− and formed a Ti-OOH intermediate, which played a key role in relaying the tandem reactions for an efficient propylene epoxidation reaction. Techno-economic analysis and life-cycle assessment revealed favorable figures for the proposed process compared to the conventional process. [ABSTRACT FROM AUTHOR]

Naringenin is a bioactive polyphenol derived from citrus fruits, known for its various beneficial effects on human health. This study focuses on naringenin as a polyphenolic scavenger of nine ultimate chemical carcinogens: 2-cyanoethylene oxide, aflatoxin B1 exo-8,9-epoxide, glycidamide, ethylene oxide, propylene oxide, styrene oxide, vinyl carbamate epoxide, chloroethylene oxide, and β-propiolactone. The aim was to calculate the activation free energies and elucidate the molecular mechanisms of alkylation reactions between naringenin and these genotoxic chemical carcinogens, using the quantum-mechanical HartreeFock method in combination with two flexible basis sets, 6-31G(d) and 6-311++G(d,p). Activation free energy calculations were performed using Gaussian 09 in a vacuum and with two implicit solvation models: Polarisable Continuum Model and Langevin Dipoles. To assess naringenin’s scavenging efficacy, the activation free energies calculated using these solvation models, were compared to the experimental values of the activation free energies between the same ultimate chemical carcinogens and the most reactive DNA base, guanine. The findings indicated naringenin's efficacy as a polyphenolic scavenger of six ultimate chemical carcinogens, particularly β-propiolactone, vinyl carbamate epoxide, and propylene oxide. For chloroethylene oxide, aflatoxin B1 exo-8,9-epoxide, and ethylene oxide, naringenin also demonstrated significant anti-carcinogenic potential, as the calculated activation free energies were comparable to experimentally determined values for guanine. However, naringenin's protective activity was less potent against 2-cyanoethylene oxide, glycidamide, and styrene oxide, where the calculated activation free energies were significantly higher than the experimental values for guanine. [ABSTRACT FROM AUTHOR]

Storing CO2 and converting it into valuable substances are crucial for addressing climate change. While poly(propylene carbonate) (PPC), formed through the copolymerization of CO2 and propylene oxide, holds promise in commercial applications, practical limitations arise due to inherent property constraints. Additionally, the lack of systematic research on PPC biodegradation complicates its post‐use disposal. In this study, we synthesized various polymers, including PPC homopolymers, PPC/castor oil star copolymers, and PPC/poly(l‐lactic acid) multiblock copolymers (PPC‐mb‐PLLAs), not only to mitigate the brittle properties of PPC but also to systematically explore their biodegradability. Both natural soil and industrial composting conditions were employed to assess the biodegradation of the polymers. Furthermore, metagenomic analysis identified the microorganisms responsible for polymer degradation, offering valuable insights into the mechanism of the biodegradation process. [ABSTRACT FROM AUTHOR]

Titanium silicalite‐1 (TS‐1) serves as an effective catalyst for propylene epoxidation in the hydrogen peroxide propylene oxide (HPPO) process, attracting wide attention from researchers and industry. Nonetheless, the TS‐1 catalyst experienced inevitable deactivation during industrial applications, which adversely impacts its lifespan. To enhance reaction stability of catalyst, the present work conducted a systematic investigation into the deactivation reason of the TS‐1 catalyst. The fresh, deactivated, and regenerated catalysts were characterized by using various analytical techniques to compare their physicochemical properties. The surface coke species of the deactivated catalysts were extracted by the Soxhlet extraction method and subsequently analyzed using GC–MS. Additionally, the pathways for by‐product formation were simulated through Gauss software. The results indicated that the so‐called coking deposits formed during the reaction predominantly consist of propylene glycol, ethers, and oligomers. These coke species covered the partial active sites on the catalyst surface, blocked the pores of the catalyst, and accordingly led to the deactivation of the catalyst, although the crystalline structure of the catalyst hardly changed after deactivation. These results provide a theoretical basis and novel insights for the rational design and development of efficient catalysts for the HPPO process. [ABSTRACT FROM AUTHOR]

Titanosilicate-supported Au-cluster catalysts can be used to selectively synthesize propylene oxide from propylene using O2 and H2. However, the details of the catalytic reaction mechanism have not yet been elucidated. Thus, the reaction mechanism was investigated using density functional theory calculations. The calculation results revealed that active Ti-OOH forms on the surface Ti site, which is active as an oxidant and acts as an anchorage site for Au nanoclusters. The rate-determining step of propylene oxide synthesis on Au/titanosilicate is O insertion into propylene, with an activation energy of 1.37 eV. The propylene involved in this reaction is activated by adsorption on Au nanoclusters. Moreover, it was also found that the formation of Ti-OOH on Au/titanosilicate requires an activation energy of 0.48 eV, while it is barrierless on Au/anatase-TiO2. However, the decomposition energy of Ti-OOH on Au/titanosilicate is −0.16 eV, which is smaller than that on Au/anatase-TiO2 (−1.12 eV). The results indicate that Ti-OOH decomposes more readily on Au/titanosilicate than on Au/anatase-TiO2 but is easily regenerated because the reaction energy is significantly smaller than that on Au/anatase-TiO2. Therefore, these calculations are qualitatively in good agreement with the experimental results for Au/titanosilicate, which exhibited high catalytic activity at high temperatures. [ABSTRACT FROM AUTHOR]

We introduce a novel concept in nucleic acid delivery based on the use of mixed polymeric micelles (MPMs) as platforms for the preparation of micelleplexes with DNA. MPMs were prepared by the co-assembly of a cationic copolymer, poly(1-(4-methylpiperazin-1-yl)-propenone)-b-poly(d,l-lactide), and nonionic poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) block copolymers. We hypothesize that by introducing nonionic entities incorporated into the mixed co-assembled structures, the mode and strength of DNA binding and DNA accessibility and release could be modulated. The systems were characterized in terms of size, surface potential, buffering capacity, and binding ability to investigate the influence of composition, in particular, the poly(ethylene oxide) chain length on the properties and structure of the MPMs. Endo–lysosomal conditions were simulated to follow the changes in fundamental parameters and behavior of the micelleplexes. The results were interpreted as reflecting the specific structure and composition of the corona and localization of DNA in the corona, predetermined by the poly(ethylene oxide) chain length. A favorable effect of the introduction of the nonionic block copolymer component in the MPMs and micelleplexes thereof was the enhancement of biocompatibility. The slight reduction of the transfection efficiency of the MPM-based micelleplexes compared to that of the single-component polymer micelles was attributed to the premature release of DNA from the MPM-based micelleplexes in the endo–lysosomal compartments. [ABSTRACT FROM AUTHOR]

Pluronics, alias poloxamers, are synthetic amphiphilic copolymers owning a triblock structure with a central hydrophobic poly(propylene oxide) (PPO) segment linked to two lateral hydrophilic poly(ethylene oxide) (PEO) chains. Commercially, Pluronics exist in numerous types according to the length of PPO and PEO chains, exhibiting different behavior and phase diagrams in solution. Concentrated aqueous solutions of Pluronics form thermoreversible gel-like systems. Properties, such as versatility, biocompatibility, nontoxicity, thermosensitivity and self-assembling behavior, make them extremely attractive for numerous applications. This review paper provides an overview on Pluronics, with a focus on their properties and phase behaviors, and on the effect of the presence of salts and additives. Different strategies to endow Pluronics with improved and extra properties, such as their chemical modification and mixed micelles, are briefly illustrated. Furthermore, a synopsis of useful experimental methodologies for understanding the flow properties of Pluronic-based systems is presented, providing a practical guide to their experimental characterization. Eventually, significant advances of Pluronic-based materials are briefly reviewed to elucidate their role in diverse applications, ranging from drug delivery and tissue engineering to bioprinting, cell cultures, personal care industry, conductive hydrogels, and electrocatalytic science. The current article is a critical review of Pluronic block copolymers, not intended as just inert materials but also as systems with functional properties able to revolutionize the paradigm of many technological fields. [ABSTRACT FROM AUTHOR]

This study presents an evaluation of the CHIMBO modeling chain applied to the Italian domain, specifically focusing on the Po Valley subdomain over the one-year period of 2019. The comparison between simulated and observed data indicates that the performance of the CHIMBO model aligns well with existing literature on other state-of-the-art models. The results demonstrate that the CHIMBO chain is particularly effective for regional-scale quantitative assessments of pollutant distribution, comparable to that of CAMS ensemble models. The analysis of key chemical species in particulate matter reveals that the CHIMBO model accurately represents the average concentrations of organic and elemental carbon, as well as secondary inorganic compounds (sulfate, nitrate, and ammonium), particularly at background monitoring stations in the flat terrain of the Po Valley, with the exception of Aosta, a city located at about 500 m asl. However, seasonal discrepancies were identified, especially during winter months, when significant underestimations were observed for several species, including elemental and organic carbon, predominantly at background sites. These underestimations are likely attributed to various factors: (i) inadequate estimations of primary emissions, particularly from domestic heating; (ii) the limited effectiveness of secondary formation processes under winter conditions characterized by low photochemical activity and high humidity; and (iii) excessive dilution of pollutants during calm wind conditions due to overestimation of wind intensity. In conclusion, while the CHIMBO modeling chain serves as a robust tool for mesoscale atmospheric composition investigations, limitations persist related to emissions inventories and meteorological parameters, which remain critical drivers of atmospheric processes. [ABSTRACT FROM AUTHOR]

The direct epoxidation of propylene with molecular oxygen represents a desired route for propylene oxide (PO) production with 100% theoretical atomic economy. However, this aerobic epoxidation reaction suffers from the apparent trade-off between propylene conversion and PO selectivity, and remains a key challenge in catalysis. We report that Ti-Beta zeolites containing isolated framework Ti species can efficiently catalyze the aerobic epoxidation of propylene. Stable propylene conversion of 25% and PO selectivity of up to 90% are achieved at the same time, matching the levels of industrial ethylene aerobic epoxidation processes. H-terminated pentacoordinated Ti species in Beta zeolite frameworks are identified as the preferred active sites for propylene aerobic epoxidation and the reaction is initiated by the participation of lattice oxygen in Ti-OH. These results are expected to spark new technology for the industrial production of PO toward more sustainable chemistry and chemical engineering. [ABSTRACT FROM AUTHOR]

In order to solve the problems of ineffective gas injection and decreased oil displacement efficiency caused by C02 gas channelling in the application of CCUS technology in low permeability reservoir, YCL modified copolymerization product of phenyl glycidyl ether and propylene oxide, was selected as a CO2 thickener in extremely low permeability reservoir, and the solubility of YCL-2 was observed by visual high・pressure vesseL The rheological properties of YCL-2 at different concentrations and temperatures were studied by rotating rheometer, and the displacement effect of YCL-2 in core groups with permeability difference of 5 and 10 was investigated ・ The plugging ability of cores with different permeability was calculated by using varied・diameter capillary bundle model to simulate the thickener system・ The results show that YCL-2 with mass concentration below 2. 0% can be completely dissolved in supercritical CO2 ・ Rheological experiments show that the shear resistance of the system decreases with the increase of temperature・ The selective injection experiment shows that the system has a certain sealing effect on the small pores of the core, and is suitable for reservoirs with permeability difference less than 5・ [ABSTRACT FROM AUTHOR]

The isolated hydrophilic black alder (Alnus glutinosa) bark extractives were characterized in terms of component and functional composition and converted at 150°C–170°C into liquid green polyols using solvent-free and low-toxic base-catalyzed modification with propylene carbonate (PC). FTIR spectroscopy, HP-LC, GC, GPC, and wet chemistry methods were used to characterize the starting constituents, intermediate and final products of the reaction and to monitor the different pathways of PC conversion. The reaction of extractives as well as the model compounds, including catechol, xylose, PEG 400, and benzoic acid, with PC indicated the ability of OH groups of different origins present in the extractives to condense with equivalent amounts of PC. The polyols obtained consist of a copolymer fraction with one oxypropyl unit grafted per OH functionality of extractive components on average and oligo oxypropyl diols with a small number of carbonate linkages in the chain, obtained as a result of remaining PC homopolymerization. The domination of the oxypropylation mechanism vs. transcarbonation for PC ring opening was observed for both copolymerization and homopolymerization processes, making the process of oxypropylation with PC similar to that of conventional oxypropylation. At optimal reaction conditions, including a PC/OH ratio of 3.0 and a 24-h duration at 150°C, uniform polyols with low viscosity of ~900 mPa·s−1, a biomass content of ~27%, and an OHV of ~500 mg KOH·g−1 were obtained. Increasing the temperature of modification allows shortening the process but drastically increases the polyol viscosity. At fixed temperature values, increasing the PC/OH ratio not only decreases the biomass content but also strongly prolongs the processing. The significantly increased duration of the process using PC as an alternative oxyalkylation agent compared to that of oxyalkylation with propylene oxide is a reasonable trade-off for using a safer and more environmentally friendly technology. [ABSTRACT FROM AUTHOR]

The polyethylene oxide‐polypropylene oxide (PEO‐PPO) based triblock copolymers are notable amphiphilic copolymers with a diverse range of applications. The presence of homo‐, and/or diblock impurities in copolymers with PEO‐PPO‐PEO triblock has been demonstrated. This finding suggests that the samples are blends rather than pure triblock copolymers. Furthermore, copolymers with triblock copolymer content of 0 or less than 20% by molar percentage have been identified. The hydrophilic‐lipophilic balance (HLB) is also calculated based on the exact composition of the blends. The effect of HLB values and compositional data on the initial foam height (in casein solution), the surface tension, and the contact angle are investigated. The correlation coefficients for the PPO‐PEO‐PPO copolymers versus HLB values are found to be high, while those obtained for the PEO‐PPO‐PEO copolymers versus values of HLB are significantly lower. The lower correlation coefficients for the PEO‐PPO‐PEO samples can be attributed to the presence of homo‐ and diblock (co)polymer contaminants. In addition, a linear regression model has been constructed to find a mathematical relationship between the percentage of ethylene oxide, the average number of propylene oxide units, and the properties of the copolymer. [ABSTRACT FROM AUTHOR]

Catalytic cycloaddition of CO2 with propylene oxide (PO) is a sustainable pathway for the synthesis of propylene carbonate (PC), and the design of efficient heterogeneous catalysts is a hot research topic in both C1 chemistry and functional materials. In this work, graphitic carbon nitride (g‐C3N4) materials were prepared using urea (U) and melamine (M) as precursors through one‐step thermal condensation and then applied as catalyst supports for ZnBr2. As heterogeneous catalysts, the synthesized composites (ZnBr2/g‐C3N4‐MU) exhibited higher activity in the cycloaddition reaction of CO2 to PC than ZnBr2/g‐C3N4‐M and ZnBr2/g‐C3N4‐U. The preparation temperature of ZnBr2/g‐C3N4‐MU could affect the distributions of nitrogen species and acidic strength, which thus determined the final catalytic activity. More importantly, the loading of ZnBr2 not only introduced acidic sites but also enhanced the strength of alkaline sites of g‐C3N4‐MU, enabling ZnBr2/g‐C3N4‐MU materials as acid–base bifunctional catalysts in cycloaddition of CO2 with PO. [ABSTRACT FROM AUTHOR]

Spin‐polarized density functional theory (DFT) +U calculation was performed to study propylene selective oxidation on Cu2O(111) and Cl−Cu2O(111) surfaces. The mechanism included two pathways: the allylic hydrogen stripping (AHS) pathway and the epoxidation pathway, and acrolein, propylene oxide (PO), propanal and acetone can be formed. The calculated results found that the C3H6*+OO*→OOMMP2*→PO* route can be regarded as the preferred formation route of PO on these two surfaces. On clean surface, acrolein can be regarded as the main product, then other products selectivity follows: acetone>PO>propanal. On Cl−Cu2O(111) surface, acrolein was also the main product, and the apparent activation energy of acrolein (1.97 eV) was approximated to the apparent activation energy of PO (2.04 eV), other products selectivity follows: PO>propanal>acetone, which means that the selectivity of PO can be improved by the effect of Cl. Microkinetic simulation confirm that PO selectivity can be elevated qualitatively, and found that OOMMP2*→PO2*+O* is the rate determining step on pure surface and C3H6*+OO*→OOMMP2* is the rate controlling step on the doped−Cl surface. From this work, it can be found the O−O bond in O2 can be activated effectively by the presence of Cl, enhancing the selectivity of PO. [ABSTRACT FROM AUTHOR]

Rational designation of the catalyst for efficient atom‐economic conversion of propylene oxide (PO) and carbon monoxide (CO) into β‐butyrolactone is of current significance. By employing the O,N,O‐tridentate ligands R1,R2LH2 (1–4), the aluminium compounds (R1,R2LAlCl)2 (R1,R2=H,H (5), tBu,tBu (6), Cl,Cl (7), Br,Br (8)) and the derived anion‐cation pairs [H,HLAl(THF)3]+[Co(CO)4]− (9) and [(R1,R2LAl)2Cl(THF)2]+[Co(CO)4]− (R1,R2=tBu,tBu (10), Cl,Cl (11), Br,Br (12)) as well as the aluminium‐cobalt bimetallic cluster compounds [(R1,R2LAl)2Cl(THF)][Co3(CO)10] (R1,R2=tBu,tBu (13), Cl,Cl (14), Br,Br (15)) were prepared. Compounds 9–12 efficiently catalyzed the PO carbonylation into β‐butyrolactone to achieve up 93.4–98.9 % yields while 13–15 gained 95.2–99.0 % yields all at 25 °C and 0.1 MPa CO pressure. The Lewis acidic property of the aluminium compounds 5–8 was investigated. The kinetic of the catalytic reaction using compound 10 was studied. The cooperatively catalytic reaction mechanism by the Co−Al bimetallic species is proposed. [ABSTRACT FROM AUTHOR]

The electrochemical propylene epoxidation reaction (PER) provides a promising route for ecofriendly propylene oxide (PO) production, instantly generating active halogen/oxygen species to alleviate chloride contamination inherent in traditional PER. However, the complex processes and unsatisfactory PO yield for current electrochemical PER falls short of meeting industrial application requirements. Herein, a spatial‐coupling strategy over RuO2/Ti hollow‐fiber penetration electrode (HPE) is adopted to facilitate efficient PO production, significantly improving PER performance to ampere level (achieving over 80 % PO faradaic efficiency and a maximum PO current density of 859 mA cm−2). The synergetic combination of the penetration effect of HPE and the spatial‐coupled reaction sequence, enables the realization of ampere‐level PO production with high specificity, exhibiting significant potentials for economically viable PER applications. [ABSTRACT FROM AUTHOR]

The quest for sustainable synthesis of carboxylic acids has led to the exploration of innovative routes and catalysts for the oxidative cleavage of carbon−carbon double bonds, prevalent in bio‐derived molecules. This process involves multiple steps including epoxidation, hydrolysis and vicinal diol cleavage, often catalysed by unsustainable homogeneous or noble‐metal catalysts. In this study, we present the utilization of Fe‐ZSM‐5 as a versatile bifunctional catalyst capable of catalysing both hydrolysis and vicinal diol cleavage steps, utilizing propylene oxide as model compound and H2O2 as oxidizing agent. The prepared Fe‐ZSM‐5 features the zeolite intrinsic Lewis and Brønsted acidity functions, essential for the hydrolysis step, as well as high fractions of monomeric FeOx species, crucial for the subsequent vicinal diol cleavage, leading to streamlined carboxylic acids formation in a one‐pot, two‐step process. Moreover, by combining Fe‐ZSM‐5 with TS‐1, renowned for its epoxidation activity, we demonstrate the complete cascade reaction in one pot, under mild conditions, starting from ethylene. Our study expands the utility of cost‐effective zeolite‐based catalysts enriched with abundant Fe metal for the one‐pot oxidative cleavage of C=C double bonds, offering a promising pathway towards sustainable carboxylic acid synthesis. [ABSTRACT FROM AUTHOR]

A comparative study of the copolymerization of racemic propylene oxide (PO) with CO2 catalyzed by racemic (salcy)CoX (salcy = N,N′-bis(3,5-di-tert-butylsalicylidene)-1,2-diaminocyclohexane; X = perfluorobenzoate (OBzF5) or 2,4-dinitrophenoxy (DNP)) in the presence of a [PPN]Cl ([PPN] = bis(triphenylphosphine)iminium) cocatalyst is performed in bulk at 21 °C and a 2.5 MPa pressure of CO2. The increase in the nucleophilicity of an attacking anion results in the increase in the copolymerization rate. Racemic (salcy)CoX provides a high selectivity of the copolymerization, which can be higher than 99%, and the living polymerization mechanism. Poly(propylene carbonate) (PPC) with bimodal molecular weight distribution (MWD) is formed throughout copolymerization. Both modes are living and are characterized by low dispersity, while their contribution to MWD depends on the nature of the attacking anion. The racemic (salcy)CoDNP/[PPN]DNP system is found to be preferable for the production of PPC with a high yield and selectivity. [ABSTRACT FROM AUTHOR]

Rationale: Ethylene oxide (EO) sterilization is commonly employed for the sterilization of medical devices and has a very high market share. However, EO and its metabolite ethylene chlorohydrin (ECH) are toxic to humans. In compliance with the classification and residue limits of medical devices defined by ISO 10993‐7, our study established two extraction methods for the testing of EO and ECH. Methods: The first method involves simulated‐use extraction using water as the extraction solvent. While the second, exhaustive extraction, directly extracts sample through headspace sampling analysis. Gas chromatography–tandem mass spectrometry in multiple reaction monitoring mode was utilized, requiring only 16 min. Then, the developed method was applied to assess 10 commercially available medical devices sterilized by EO. Results: In simulated‐use extraction, calibration curves were evaluated in the range of 1–100 and 5–500 μg for EO and ECH, respectively (r > 0.999). Inter‐day recoveries ranged from 85.0% to 95.2% and from 94.8% to 102.4%. In exhaustive extraction, calibration curves spanned 0.5–50 and 2–200 μg for EO and ECH, respectively (r > 0.999). Inter‐day recoveries ranged from 101.6% to 102.1% for EO and from 98.1% to 102.2% for ECH. After analysis of the 10 commercially available medical devices, two cotton swabs were found to have ECH of 35.1 and 28.4 μg per device, and four medical devices were found to have EO with concentration below the limit of quantification. Meanwhile, we found that the EO internal standard (propylene oxide) recommended by ISO 10993‐7 had interference problems with other similar substances and was not suitable as an internal standard for EO. Conclusions: This study offers a sensitive and straightforward analytical approach to EO and ECH residues in a variety of medical devices. In addition, the results show that the EO or ECH content of these types of medical devices in our study falls below the regulatory limits, therefore instilling confidence among consumers regarding their safe use. [ABSTRACT FROM AUTHOR]

The polymerization and degradation behaviors of polypropylene carbonate (PPC) of different molecular weights were explored in the presence of catalyst Salen–Co(III)–Cl. The degradation of low-molecular-weight PPC (Mn = 2500 g mol−1, Đ = 1.01) was studied in detail, which was a second-order reaction related to the molar concentrations of PPC and the catalyst. Catalyzed by salen–cobalt, the degradation reaction proceeded spontaneously and could be completed at room temperature and atmospheric pressure, which provided a green and economical method for chemical degradation recycling of CO2-based polycarbonate plastics. On the basis of the degradation investigation, a method for the synthesis of cyclic propylene carbonate from propylene oxide and CO2 at room temperature and atmospheric pressure was developed. [ABSTRACT FROM AUTHOR]

A series of hollow VOx/SiO2 nanofiber catalysts (nV/S-f) with vanadium content ranging from 0.25 wt% to 4.0 wt% were prepared by electrospinning-calcination, and characterized by ICP-MS, XRD, N2 adsorption–desorption, SEM, XPS, UV–Vis-DRS and H2-TPR. Subsequently, the performance of these catalysts in the oxidative dehydrogenation of propane (ODHP) was evaluated. It was found that vanadium species with high dispersivity were obtained when the V content was less than 1.5 wt%. By comparison, 1.0V/S-f catalyst had the best catalytic performance, especially in terms of the propylene selectivity at high-temperature: ~ 77% at 550 °C and ~ 74% at 575 °C. In contrast to the conventional impregnation technique, the catalyst with one-dimensional nanostructure has more catalytic advantages. [ABSTRACT FROM AUTHOR]

This study describes the physicochemical characterisation of interpenetrating hydrogel networks (IHNs) composed of either poly(hydroxyethylmethacrylate, p(HEMA)) or poly(methacrylic acid, p(MAA)), and Pluronic block copolymers (grades F127, P123 and L121). IHNs were prepared by mixing the acrylate monomer with Pluronic block copolymers followed by free radical polymerisation. p(HEMA)–Pluronic blends were immiscible, evident from a lack of interaction between the two components (Raman spectroscopy) and the presence of the glass transitions (differential scanning calorimetry, DSC) of the two components. Conversely, IHNs of p(MAA) and each Pluronic were miscible, displaying a single glass transition and secondary bonding between the carbonyl group of p(MAA) and the ether groups in the Pluronic block copolymers (Raman and ATR-FTIR spectroscopy). The effect of storage of the IHNs in Tris buffer on the physical state of each Pluronic and on the loss of Pluronic from the IHNs were studied using DSC and gravimetric analysis, respectively. Pluronic loss from the IHNs was dependent on the grade of Pluronic, time of immersion in Tris buffer, and the nature of the IHN (p(HEMA) or p(MAA)). At equilibrium, the loss was greater from p(HEMA) than from p(MAA) IHNs, whereas increasing ratio of poly(propylene oxide) to poly(ethylene oxide) decreased Pluronic loss. The retention of each Pluronic grade was shown to be primarily due to its micellization; however, hydrogen bonding between Pluronic and p(MAA) (but not p(HEMA)) IHNs contributed to their retention. [ABSTRACT FROM AUTHOR]

Double metal cyanide (DMC) complexes represent a unique family of materials with an open framework structure. The main current application of these complexes in chemical industry is their use as catalysts (DMCCs) of the ring-opening polymerization of propylene oxide (PO), yielding branched polyols, highly demanded in production of polyurethanes and surfactants. The actual problem of chemical fixing carbon dioxide from the atmosphere gave new impetus to the development of DMCCs, which turned out to be effective in oxirane/CO2 copolymerization. In recent years, new types and formulations of DMCCs were created, so that greater understanding of the reaction mechanisms was achieved and new fields of catalytic applications were found. In the present review, we summarized background and actual information about the synthesis, structure, and mechanisms of the action of DMCCs, as well as their application in the development of new materials and fine chemicals. [ABSTRACT FROM AUTHOR]

A PPC‐dodecyl glucoside (PPC‐APG) polymer was synthesized by the terpolymerization of carbon dioxide (CO2), propylene oxide (PO), and the bio‐based monomer APG for the first time. The thermal stability and mechanical properties of PPC‐APG were significantly improved compared with those of conventional polypropylene carbonate (PPC), and its glass transition temperature (Tg) was increased by 14°C compared with that of PPC. The 5% heat loss temperature (Td,−5%) and total heat loss temperature (Td,max) of PPC‐APG were increased by 89.1 and 92.1°C, respectively, compared with those of PPC. The tensile strength of PPC‐APG was increased to 25.6 MPa, its elongation at break was decreased to 125.1%, and its thermal elongation and permanent deformation were reduced to 97.2% and 62.9%, respectively, which improved the processability of the material. In addition, the introduction of bio‐based monomers also rendered PPC‐APG functional, and its surface tension reached a maximum of 61.3 mN/m at a concentration of 0.05 g/mL, with a good degradability. The higher surface tension and enhanced degradability of PPC‐APG indicate its potential for application as a plastic printing substrate. [ABSTRACT FROM AUTHOR]

Sago starch is a locally abundant starch indigenous of Indonesia. Despite its abundance, it is underutilized and restricted to food and packaging applications due to its limited functional characteristics. The value of native sago starch can be increased through modifications that improve its functionality, such as dual chemical modification. This sophisticated approach is more effective than single modification and makes the starch suitable for wider applications. Our study aimed to determine if dual chemical modification involving hydroxypropylation and succinylation would optimize the functional properties of sago starch. The sago starch was first modified by hydroxypropylation with 7 % (w/w) propylene oxide under alkaline conditions for 3 hours. This process resulted in hydroxypropylated starch with a substitution degree of 0.107. We then subjected the starch to succinylation using succinic anhydride at 1 % to 5 % of the starch weight in an alkaline solution for 2 hours. We achieved optimal functional characteristics of the dual-modified sago starch in the sample modified with 3 % (w/w) of succinic anhydride. The succinyl degree of substitution, water holding capacity, oil holding capacity, swelling power, and solubility of the dual-modified starch were 0.093, 4.16 g g􀀀1, 7.20 g g􀀀1, 34.25 g g􀀀1, and 16:55 %, respectively. We conducted pasting properties analyses, infrared spectroscopy, and morphological structure analysis to determine the changes in the characteristics of the sago starch after hydroxypropylation and succinylation. The dual chemical modification successfully enhanced the functional characteristics of sago starch, particularly, its amphiphilic ability and swelling power. These results warrant further research and development in commercial applications.

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The design and synthesis of efficient carbon‐based materials incorporating multifunctional sites is prospective technology for converting carbon dioxide (CO2) into high‐value chemicals. Here, nitrogen‐doped carbon catalysts (ZnAl‐NC) with bimetal zinc–aluminum sites were synthesized using nitrogen‐rich polyaniline (PANI) and ZnAl‐LDH through hydrothermal and in situ pyrolysis methods. ZnAl‐NC‐400, in the presence of tetrabutylammonium bromide (TBAB), exhibited excellent catalytic activity without solvent, achieving high yields (97.2% or 98.5%) in the cycloaddition of CO2 with propylene oxide (PO) under traditional or mild conditions. NH3‐TPD and CO2‐TPD results indicated that the enhanced catalytic activity resulted from the acid–base synergistic effect, involving Lewis acid sites from Zn and Al species and abundant Lewis base sites from the PANI matrix. The impact of calcination temperature on catalyst morphology, structure, and performance was investigated, along with catalyst recycling and adaptability to various epoxides. This work presents an efficient catalyst for CO2 conversion and suggests new approaches for designing catalytic sites in carbon‐based catalysts for CO2 capture and utilization. [ABSTRACT FROM AUTHOR]

A hierarchical structure alumina with high surface area was synthesized using a sol-gel method assisted by propylene oxide (PO), which was subsequently converted into alumina exhibiting different transitional phases (γ, δ, θ) through varying calcination temperatures. These aluminas were employed as substrates for the active copper phase in the RWGS catalyst, facilitating a systematic exploration of how the alumina phase influences catalyst performance. The characterized catalysts underwent assessments using techniques such as N 2 adsorption-desorption, XRD, H 2 -TPR, CO 2 -TPD, FESEM, and HRTEM. An examination of the impact of copper loading (ranging from 5.0 to 20.0 wt%) in the Cu/γ-Al 2 O 3 catalyst on RWGS performance revealed that the catalyst containing 15.0 wt% Cu exhibited the highest CO 2 conversion rate, achieving 8% at 300 °C under a 1CO 2 :1H 2 ratio at atmospheric pressure. This specific catalyst demonstrated 100% selectivity for CO. Evaluating the extended stability of Cu catalysts supported by γ-, δ-, and θ-Al 2 O 3 phases, all loaded with the same amount of Cu (15.0 wt%), was carried out at 450 °C. The δ- and θ-Al 2 O 3 -supported catalysts were able to maintain approximately 100% of their initial catalytic activities after 72 h, whereas the activity of the catalyst supported by γ-Al 2 O 3 decreased. The examination of the crystalline phases of the catalyst support and stability testing demonstrated the significant impact of porosity on mass transfer and the diffusion processes of reactants and production on the structure of the catalyst. This study revealed how adjusting the macropore size and porosity within various crystalline phases can optimize the filling degree and achieve an ideal balance between reaction and mass transfer rates. [Display omitted] • Catalyst support with the highest surface area was prepared via a sol-gel method. • Effect of hierarchical alumina as catalyst support was investigated in RWGS reaction. • 15 wt% Cu/γ-Al 2 O 3 catalyst exhibited the highest CO 2 conversion of 8% at 300 °C. • CO selectivity was 100% over 15 wt% Cu/γ-, δ-, and θ-Al 2 O 3 catalysts. [ABSTRACT FROM AUTHOR]

Selective polymerization with heterogeneous catalysts from mixed monomers remains a challenge in polymer synthesis. Herein, we describe that nano-sized zinc glutarate (ZnGA) can serve as a catalyst for the selective copolymerization of phthalic anhydride (PA), propylene oxide (PO) and lactide (LA). It was found that the ring-opening copolymerization (ROCOP) of PA with PO occurs firstly in the multicomponent polymerization. After the complete consumption of PA, the ring-opening polymerization (ROP) of LA turns into the formation of block polyester. In the process, the formation of zinc–alkoxide bonds on the surface of ZnGA accounts for the selective copolymerization from ROCOP to ROP. These results facilitate the understanding of the heterogeneous catalytic process and offer a new platform for selective polymerization from monomer mixtures. [ABSTRACT FROM AUTHOR]

The chemical industry must reduce greenhouse gas emissions to align with the Paris Agreement. In this study, we assess the economic feasibility of electrochemical oxidations (i.e., using water and electricity to create reactive oxygen species) as an alternative to current energy- and emissions-intensive industrial methods for producing ethylene oxide (EO) and glycol (EG) and propylene oxide (PO) and glycol (PG). Technoeconomic analyses reveal ethylene electrooxidations in a gas diffusion electrode assembly reach economic viability at single-pass conversions above 70% for EO and 40% for EG with overall Faradaic efficiencies (FE) above 20% and high carbon selectivities toward the desired products. Propylene electrooxidation achieves economic feasibility at a minimum single-pass conversion of 10% and overall FE greater than 10% for both PO and PG, while allowing variance in carbon selectivity. These electrochemical methods require current densities of at least 0.1 A cm-2 and lifetimes greater than 2 years for industrial scalability. We demonstrate that electrochemical oxidations can reduce emissions and operational hazards in the production of key chemical intermediates through benchmarking targets for the experimental advancement of alkene electrooxidations. [ABSTRACT FROM AUTHOR]