Polar Carboxyl Research Articles

Polymerizable fatty acid surfactant: Encapsulation of organic pigments for excellent colloidal stability in aqueous solution and water-repellent property

Organic pigments are indispensable in various applications due to their vibrant colors and durability, yet their low polarity often hinders their dispersion in an aqueous solution, leading to large aggregation and sedimentation. To address these limitations, dispersants and encapsulation techniques have been explored. In this study, nanoscale encapsulated pigments were synthesized using a novel polymerizable surfactant, sodium 11-methacrylamidoundecanoic acid (NaMAAUA), along with hydrophobic monomer of styrene or butyl methacrylate. NaMAAUA contains a pendant group of amphiphilic fatty acid, and acts as a dispersant and emulsifier, forming a copolymer shell around the pigments. The apolar tail in NaMAAUA provides hydrophobic interaction with pigments, and the polar carboxyl headgroup exposes in the water phase and enables the formation of strong hydrogen bonds with cellulose. Therefore, the resulting encapsulated pigment exhibits excellent dispersion stability, water-repellent property, washing fastness and UV resistance when applied to paper and cotton fabric, expanding the practical utility of organic pigments in an environmentally conscious manner. Characterization via various analytical techniques validates the efficacy of this approach, paving the way for enhanced pigment applications.

Designing multifunctional, 3D cross-linked network binder for actual use in high performance lithium ion batteries silicon based anodes

Binders have been proved to be an economical and effective approach for accelerating the industrial application of silicon based anodes. Herein, a 3D network binder (H-PAN-g-ECH) with multifunctional groups, is constructed by crosslinking polyacrylonitrile (PAN) hydrolysate (H-PAN) with epichlorohydrin (ECH). Strong polar groups carboxylate (-COO-) and amide (-CONH2) obtained from hydrolysis of PAN as well as the original cyanide (-CN) enhance the adhesive ability of H-PAN-g-ECH to not only active material but also current collector, and thus sustain the structure integrity of the electrode. In addition, the network structure proposed by linking H-PAN with short-chain molecules endows H-PAN-g-ECH with facilitated Li-ion transmission and improved mechanical property to accommodate the great volume variation of Si during cycling. The as-prepared H-PAN-g-ECH possesses multiple interfacial adhesion and robust mechanical performance, which improves the electrochemical property of silicon anode with high areal capacity. In combination with good processability, H-PAN-g-ECH is verified to be a superior binder in use of practical Si based anodes.

Unimolecular Chemiexcited Oxygenation of Pathogenic Amyloids

AbstractPathogenic protein aggregates, called amyloids, are etiologically relevant to various diseases, including neurodegenerative Alzheimer disease. Catalytic photooxygenation of amyloids, such as amyloid‐β (Aβ), reduces their toxicity; however, the requirement for light irradiation may limit its utility in large animals, including humans, due to the low tissue permeability of light. Here, we report that Cypridina luciferin analogs, dmCLA‐Cl and dmCLA‐Br, promoted selective oxygenation of amyloids through chemiexcitation without external light irradiation. Further structural optimization of dmCLA‐Cl led to the identification of a derivative with a polar carboxylate functional group and low cellular toxicity: dmCLA‐Cl‐acid. dmCLA‐Cl‐acid promoted oxygenation of Aβ amyloid and reduced its cellular toxicity without photoirradiation. The chemiexcited oxygenation developed in this study may be an effective approach to neutralizing the toxicity of amyloids, which can accumulate deep inside the body, and treating amyloidosis.

Unimolecular Chemiexcited Oxygenation of Pathogenic Amyloids.

Pathogenic protein aggregates, called amyloids, are etiologically relevant to various diseases, including neurodegenerative Alzheimer disease. Catalytic photooxygenation of amyloids, such as amyloid-β (Aβ), reduces their toxicity; however, the requirement for light irradiation may limit its utility in large animals, including humans, due to the low tissue permeability of light. Here, we report that Cypridina luciferin analogs, dmCLA-Cl and dmCLA-Br, promoted selective oxygenation of amyloids through chemiexcitation without external light irradiation. Further structural optimization of dmCLA-Cl led to the identification of a derivative with a polar carboxylate functional group and low cellular toxicity: dmCLA-Cl-acid. dmCLA-Cl-acid promoted oxygenation of Aβ amyloid and reduced its cellular toxicity without photoirradiation. The chemiexcited oxygenation developed in this study may be an effective approach to neutralizing the toxicity of amyloids, which can accumulate deep inside the body, and treating amyloidosis.

Low-Temperature Deposited Amorphous Poly(aryl ether ketone) Hierarchically Porous Scaffolds with Strontium-Doped Mineralized Coating for Bone Defect Repair.

In recent years, the demand for clinical bone grafting has increased. As a new solution for orthopedic implants, polyether ether ketone (PEEK, crystalline PAEK) has excellent comprehensive performance and is practically applied in the clinic. In this research, a noteworthy elevated scheme to enhance the performance of PEEK scaffolds is presented. The amorphous aggregated poly (aryl ether ketone) (PAEK) resin is prepared as the matrix material, which maintains high mechanical strength and can be processed through the solution. So, the tissue engineering scaffolds with multilevel pores can be printed by low-temperature deposited manufacturing (LDM) to improve biologically inert scaffolds with smooth surfaces. Also, the feature of PAEK's solution processing is profitable to uniformly add the functional components for bone repair. Ultimately, A system of orthopedic implantable PAEK material based on intermolecular interactions, surface topology, and surface modification is established. The specific steps include synthesizing PAEK that contain polar carboxyl structures, preparing bioinks and fabricating scaffolds by LDM, preparation of scaffolds with strontium-doped mineralized coatings, evaluation of their osteogenic properties in vitro and in vivo, and investigation on the effect and mechanism of scaffolds in promoting osteogenic differentiation. This work provides an upgraded system of PAEK implantable materials for clinical application.

Stable anode/separator interface enabled by graft modification of polypropylene separator via electron beam irradiation technique toward high-performance sodium metal batteries

Sodium metal batteries (SMBs) are considered as strong alternatives to lithium-ion batteries (LIBs), due to the inherent merits of sodium metal anodes (SMAs) including low redox potential (−2.71 V vs. SHE), high theoretical capacity (1166 mAh g−1), and abundant resources. However, the uncontrollable Na dendrite growth has significantly impeded the practical deployment of SMBs. Separator modification has emerged as an effective strategy for substantially enhancing the performance of SMAs. Herein, for the first time, we present the successful grafting polyacrylic acid (PAA) onto polypropylene (PP) separators (denoted as PP-g-PAA) using highly efficient electron beam (EB) irradiation to improve the cyclability of SMAs. The polar carboxyl groups of PAA can facilitate the electrolyte wetting and provide ample mechanical strength to resist dendrite penetration. Consequently, the regulation of Na+ ion flux enables uniform Na+ deposition with dendrite-free morphology, facilitated by the favorable anode/separator interface. The PP-g-PAA separator significantly enhances the cyclability of fabricated cells. Notably, the lifespan of Na||Na symmetric cells can be extended up to 5519 h at 1 mA cm−2 and 1 mAh cm−2. The stable design of the anode/separator interface achieved through polyolefin separator modification presented in this study holds promise for the further advancement of next-generation advanced battery systems.

Achieving Dendrite-Free Zinc Metal Anodes via Molecule Anchoring and lon-Transport pumping.

The potential for scale-up application has been acknowledged by researchers for rechargeable aqueous zinc-ion batteries (ZIBs). Nonetheless, the progress of the development is significantly impeded due to the instability of the interface between the zinc anode and electrolyte. Herein, efficient and environmentally benign valine (Val) were introduced as aqueous electrolyte additive to stabilize the electrode/electrolyte interface (EEI) via functional groups in additive molecules, thus achieving reversible dendrite-free zinc anode. The amino groups present in Val molecules have a strong ability to adsorb on the surface of zinc metal, enabling the construction of anchored molecular layer on the surface of zinc anodes. The strongly polar carboxyl groups in Val molecules can act as ion-transport pumps to capture zinc ions in the electric double layer (EDL) through coordination chemistry. Therefore, this reconstructed EEI could modulate the zinc ion flux and simultaneously suppress side reactions and dendritic growth of Zn. Consequently, a long stable cycling up to 1400 h at a high current density of 20 mA cm-2 is achieved. Additionally, Zn//V2O5 full cell with Val additive exhibit enhanced cyclability, retaining 77 % capacity after 3000 cycles, displaying significant potential in promoting the commercialization of ZIBs.

Constructing high-toughness polyimide binder with robust polarity and ion-conductive mechanisms ensuring long-term operational stability of silicon-based anodes

Silicon-based materials have demonstrated remarkable potential in high-energy–density batteries owing to their high theoretical capacity. However, the significant volume expansion of silicon seriously hinders its utilization as a lithium-ion anode. Herein, a functionalized high-toughness polyimide (PDMI) is synthesized by copolymerizing the 4,4′-Oxydiphthalic anhydride (ODPA) with 4,4′-oxydianiline (ODA), 2,3-diaminobenzoic acid (DABA), and 1,3-bis(3-aminopropyl)-tetramethyl disiloxane (DMS). The combination of rigid benzene rings and flexible oxygen groups (-O-) in the PDMI molecular chain via a rigidness/softness coupling mechanism contributes to high toughness. The plentiful polar carboxyl (–COOH) groups establish robust bonding strength. Rapid ionic transport is achieved by incorporating the flexible siloxane segment (Si-O-Si), which imparts high molecular chain motility and augments free volume holes to facilitate lithium-ion transport (9.8 × 10−10 cm2 s−1 vs. 16 × 10−10 cm2 s−1). As expected, the SiOx@PDMI-1.5 electrode delivers brilliant long-term cycle performance with a remarkable capacity retention of 85% over 500 cycles at 1.3 A g−1. The well-designed functionalized polyimide also significantly enhances the electrochemical properties of Si nanoparticles electrode. Meanwhile, the assembled SiOx@PDMI-1.5/NCM811 full cell delivers a high retention of 80% after 100 cycles. The perspective of the binder design strategy based on polyimide modification delivers a novel path toward high-capacity electrodes for high-energy–density batteries.

Original Synthesis of Ethylene‐Acrylic Acid (ester) Copolymers Derivatives from 5‐substituted Cyclooctenes with A Controllable Way Via Ring‐Opening Metathesis Polymerization

AbstractHigh‐value grades of ethylene‐acrylic acid (EAA) and ethylene‐acrylic ester copolymers have been producing produced from ethylene, acrylic acid (AA), and the alcohol derivative via radical reaction in autoclave reactor at a temperature of 150‒230 °C and pressure of 150–300 MPa. In this paper, EAA and its ester derivatives are originally created from the 5‐substituted cyclooctenes (COE) with side chains of carboxylic acid or ester derivatives by ring‐opening metathesis polymerization (ROMP) at normal temperature and pressure. Especially, the controllable insertion of side chain is effectively achieved by altering the molar ratio of COE and 5‐substituted COE. Furthermore, the polar carboxyl groups (ester groups) have a detrimental effect on the order assigns of the linear backbone and thus hindered crystallization, indicating relatively lower crystallizing and melting temperature with an increase in the content of side chain. As the amounts of polar groups raised, the stiffness of chain segments enhanced, thereby leading to an elevation in the copolymer's energy storage modulus (E') and glass transition temperature (Tg). Moreover, the Flynn‐Wall‐Ozawa (FWO) technique is employed to characterize and fit the non‐isothermal crosslinking kinetics of the ethylene‐acrylic ester derivatives, and the crosslinking activation energy is determined to lie between 97 and 140 kJ mol−1.

Inert Group-Containing Electrolyte Additive Enabling Stable Aqueous Zinc-Ion Batteries.

Aqueous zinc ion batteries (AZIBs) are considered promising energy storage devices because of their high theoretical energy density and cost-effectiveness. However, the ongoing side reactions and zinc dendrite growth during cycling limit their practical application. Herein, trisodium methylglycine diacetate (Na3MGDA) additive containing the additional inert group methyl is introduced for Zn anode protection, and the contribution of methyl as an inert group to the Zn anode stability is discussed. Experimental results reveal that the methyl group with various effects enhances the interaction between the polar groups in Na3MGDA and the Zn2+/Zn anode. Thus, the polar carboxylate negative ions in MGDA anions can more easily modify the solvation structure and adsorb on the anode surface in situ to establish a hydrophobic electrical double layer (EDL) layer with steric hindrance effects. Such the EDL layer exhibits a robust selectivity for Zn deposition and a significant inhibition of parasitic reactions. Consequently, the Zn||Zn symmetric battery presents 2375h at 1mAcm-2, 1mAhcm-2, and the Zn||V6O13 full battery provides 91% capacity retention after 1300 cycles at 3Ag-1. This study emphasizes the significant role of inert groups of the additive on the interfacial stability during the plating/stripping of high-performance AZIBs.

Preparation of molecularly imprinted polymer nanoparticles for selective adsorption of caffeine using dual-functionalized Ag2S quantum dots

Caffeine is the most abundant and widely consumed active medicinal compound, making it the most representative pollutant in the environment. This research involved synthesizing high-performance fluorescent HOOC-CC-functionalized Ag2S quantum dots (HOOC-QDs) measuring approximately 4.35 nm in size using the hydrothermal method. These QDs were then used to produce fluorescent molecularly imprinted polymer nanoparticles (MIP-Ag2S NPs) measuring 20.31 nm. The MIP-Ag2S NPs were created through a graft suspension copolymerization process involving methacrylic acid monomer, ethylene glycol dimethacrylate cross-linker, and caffeine template molecules. The polar carboxylic acid groups enhance the interaction with the template molecules, which is crucial for selectivity, and the -CC- groups aid in network formation. The MIP-Ag2S NPs emitted fluorescence at around 500 nm, which was significantly reduced after caffeine adsorption. The pH-sensitive MIP-Ag2S NPs had a maximum caffeine adsorption capacity of 488 mg/g at pH 6 and a maximum release of approximately 96% at pH 2.2. Additionally, repeated cycles of adsorption and desorption did not result in a significant loss of adsorption capacity. The HOOC-QDs can be used to prepare MIPs for extracting and recognizing pollutants and medicine in water and for controlled drug delivery systems.

Effects of surfactant with different injection times on asphaltene adsorption behaviors on the kaolinite surfaces: A molecular simulation study

The adsorption behavior of asphaltenes on the mineral surfaces seriously reduces oil recovery, which is dependent on the molecular structure, surface properties of the inorganic minerals, and the injection time of chemicals. In the present study, the molecular dynamics (MD) simulation is performed to construct the asphaltene-kaolinite adsorption systems and the 3-(N,N-Dimethyloctadecylammonio) propane sulfonate (DOPS) surfactant flooding systems to explore the effect of DOPS injection times on the detachment of asphaltene aggregates with discrepant adsorption characteristics. The number density distribution and the interaction analysis between asphaltene and kaolinite are employed to evaluate the adsorption behaviors of asphaltene on the kaolinite-liquid interfaces. The radial distribution function (RDF) describes the relative positions of the surfactants and asphaltene aggregates. The effective free energy and the independent gradient model based on Hirshfeld partition (IGMH) method further illustrate the microscopic mechanism of asphaltene detaching by the surfactant. The simulation results indicate that intensely polar carboxylate groups and polyaromatic rings with π-conjugated structures dominate the adsorption behavior of asphaltenes. The DOPS surfactants injected after the water flooding are difficult to produce effective ways of detaching asphaltenes, while the introduced DOPS surfactants during water flooding can generate DOPS-ASPn combinations to detach asphaltene from the kaolinite surfaces. This work first investigates the effects of surfactants with different injection times on the oil detachment efficiency at a molecular scale, further deepening the understanding of oil detachment process via surfactant flooding.

CIL-ExPMRM: An Ultrasensitive Chemical Isotope Labeling Assisted Pseudo-MRM Platform to Accelerate Exposomic Suspect Screening.

Exposome is the future of next-generation environmental health to establish the association between environmental exposure and diseases. However, due to low concentrations of exposure chemicals, exposome has been hampered by lacking an effective analytical platform to characterize its composition. In this study, by combining the benefit of chemical isotope labeling and pseudo-multiple reaction monitoring (CIL-pseudo-MRM), we have developed one highly sensitive and high-throughput platform (CIL-ExPMRM) by isotope labeling urinary exposure biomarkers. Dansyl chloride (DnsCl), N-methylphenylethylamine (MPEA), and their isotope-labeled forms were used to derivatize polar hydroxyl and carboxyl compounds, respectively. We have programmed a series of scripts to optimize MRM transition parameters, curate the MRM database (>70,000 compounds), predict accurate retention time (RT), and automize dynamic MRMs. This was followed by an automated MRM peak assignment, peak alignment, and statistical analysis. A computational pipeline was eventually incorporated into a user-friendly website interface, named CIL-ExPMRM (http://www.exposomemrm.com/). The performance of this platform has been validated with a relatively low false positive rate (10.7%) across instrumental platforms. CIL-ExPMRM has systematically overcome key bottlenecks of exposome studies to some extent and outperforms previous methods due to its independence of MS/MS availability, accurate RT prediction, and collision energy optimization, as well as the ultrasensitivity and automated robust intensity-based quantification. Overall, CIL-ExPMRM has great potential to advance the exposomic studies based on urinary biomarkers.

Manipulating the Thermal Conductivity of the Graphene/Poly(vinyl alcohol) Composite via Surface Functionalization: A Multiscale Simulation.

The reverse non-equilibrium molecular dynamics simulation is used to investigate the influence of functional groups (FGs) on the thermal conductivity of a graphene/poly(vinyl alcohol) (PVA) composite, which considers non-polar (methyl) and polar (hydroxyl, amino, and carboxyl) groups. First, the polar groups can be more effective to improve the interfacial thermal conductivity than the non-polar group. This can be explained well by characterizing the interfacial Coulombic energy, number and lifetime of hydrogen bonds, vibrational density of states, and integrated autocorrelation of the interfacial heat power. Moreover, the hydroxyl group can improve the interfacial thermal conductivity more than the other groups, which can be rationalized by analyzing the surface roughness of graphene and the radial distribution function of FGs and the PVA chains. However, the introduction of FGs destroys the graphene structure, which consequently reduces the intrinsic thermal conductivity. Furthermore, by adopting the effective medium approximation model and finite element method, there exists a critical graphene length where the overall thermal conductivities are equal for the functionalized and pristine graphene. Finally, the distribution state of graphene is emphasized to be more vital in determining the overall thermal conductivity than the generally accepted interfacial thermal conductivity.

An Amphiphilic Peptide Carrier for HCl Transport.

Single molecules that co-transport cations as well as anions across lipid membranes are few despite their high biological utility. The elegant yet simple lipidomimetic peptide design herein enables efficient HCl transport without the use of any external additives for proton transport. The carboxylic acids in the dipeptide scaffold provide a handle to append two long hydrophobic tails and also provides a polar hydrophilic carboxylate group. The peptide central unit also provides NH sites for anion-binding. Protonation of the carboxylate group coupled with the weak halide binding of the terminal NH group results in HCl transport with transport rates of H+ > Cl‾. The lipid-like structure also facilitates seamless membrane integration and flipping of the molecule. The biocompatibility, design simplicity and potential pH regulation of these molecules open up several avenues for their therapeutic use.

Roles of chemistry modification for surface wettability of Polyether-Ether-Ketone (PEEK) by ultraviolet laser ablation

Tailoring the functionality of Polyether-ether-ketone (PEEK) is critical for enhancing its application, which can be accomplished by the modification of surface morphology and chemistry. In the present work, we experimentally demonstrate the correlation of modified chemical composition of textured PEEK surface by 355 nm UV nanosecond pulsed laser ablation with enhanced surface wettability. Specifically, the impact of UV laser processing parameters on microgroove morphology and ablated surface quality of PEEK surface is evaluated, with which high precision grid surface textures with uniform ablation quality are fabricated. The modification of chemical elements and functional groups of textured PEEK surface by the laser ablation is further analyzed by XPS spectra characterization, which demonstrates the substantial change of C=O and O–C=O bonds, as well as freshly generated polar carboxylic acid groups. Experimental results indicate that the surface composition modification greatly increases surface polarity and surface free energy of textured PEEK surface accompanied by enhanced surface wettability.

Microporous, Crystalline, and Water‐Processable Framework Materials of Organic Amphiphile Salts

AbstractPorous framework materials are of major importance for a wide range of technologies. Nevertheless, many of these materials lack processibility as they are typically synthesized under rather harsh conditions and obtained as microcrystalline powders that cannot easily be coated or deposited from solution. Herein, a new approach to water‐processable metal–organic framework materials is presented. The materials are based on amphiphilic organic building blocks consisting of polar carboxylate groups and non‐polar alkyl chains connected to a rigid aromatic core. The amphiphilic building blocks assemble to porous framework structures via bonding to kinetically labile sodium ions from concentrated aqueous solution. The obtained crystalline materials, termed amphiphile salt frameworks , are thermally and mechanically stable (some derivatives up to 365 °C and up to at least 4000 bar hydrostatic pressure), exhibit persistent microporous channels accessible to several gases (N2, CO2, propane, propylene, n‐butane), and can be reversibly assembled/disassembled by crystallization from or dissolution in water. Systematic variation of the hydrophobic side chains of the amphiphile building blocks allows extracting structure‐property relationships and first design rules for this new class of water‐processable microporous framework materials.

Achieving Fast and Reversible Sulfur Redox by Proper Interaction of Electrolyte in Potassium Batteries

Potassium–sulfur batteries have potential for low-cost and high-energy density energy storage. However, it is a challenge to find suitable electrolytes affording liquid environment for intermediate sulfur species to convert at high voltages. In this study, a series of ether/potassium salt systems were systematically studied to investigate the electrochemical stability and function of the electrolytes in sulfur electrochemistry by using in situ ultraviolet–visible and Fourier-transform infrared spectroscopies. Interactions of soluble polysulfides with the electrolyte were critical to the electrochemical performance. Under optimized conditions, the bis(trifluoromethanesulfonyl)imide anion demonstrated moderate interaction and reversible solvation/desolvation of polysulfides. Polar carboxyl groups in poly(acrylic acid) were effective for binding polysulfide in electrodes, enabling reversible sulfur conversions at high working voltages and improved initial Coulombic efficiency. This enhanced battery performance was achieved even using a conventional carbon host with a high sulfur loading of ∼69 wt %, i.e., ∼49 wt % in the cathode.

How triazole rings capture carbon dioxide: Energy effects and activation barriers

The interest in carbon dioxide (CO2) sorbents is fostered by the global peril of climate warming. Herein, we examine a new class of potential CO2 scavengers, 1,2,3-triazoles, the current-year Nobel Prize winners. Their affinities to CO2 were characterized in terms of reaction energy profiles, nucleophilicities of the respective in-ring nitrogen atoms, and continuous geometry alterations during the course of the chemical reactions. We computationally revealed varying abilities of 1,2,3-triazoles and the triazolide anion to chemically fix CO2 via the carboxamidation mechanism and linked them to electron density distributions over the triazole rings. The triazolide anions in a dilute solution and ion pairs of tetraethylammonium 1,2,3-triazolide exhibit competitive CO2 sorption capacities, whereas neutral 1,2,3-triazoles were confirmed to be quite weak bases. The presence of an excessive electron in the heterocyclic anion enhances the nucleophilicities of the three nitrogen atoms and, therefore, gives rise to a promising CO2 scavenger. The solvation in water strongly fosters carboxamidation (decreases both the activation barrier and the energetic effect) in most cases thanks to the emergence of polar carboxyl moiety. The reported new knowledge is necessary to rationally rate manifold classes of nitrogen-containing heterocyclic compounds for the sake of searching for chemically robust and economically affordable CO2 scavengers.

Chemoselective Decarboxylative Protonation Enabled by Cooperative Earth‐Abundant Element Catalysis

AbstractDecarboxylative protonation is a general deletion tactic to replace polar carboxylic acid groups with hydrogen or its isotope. Current methods rely on the pre‐activation of acids, non‐sustainable hydrogen sources, and/or expensive/highly oxidizing photocatalysts, presenting challenges to their wide adoption. Here we show that a cooperative iron/thiol catalyst system can readily achieve this transformation, hydrodecarboxylating a wide range of activated and unactivated carboxylic acids and overcoming scope limitations in previous direct methods. The reaction is readily scaled in batch configuration and can be directly performed in deuterated solvent to afford high yields of d‐incorporated products with excellent isotope incorporation efficiency; characteristics not attainable in previous photocatalyzed approaches. Preliminary mechanistic studies indicate a radical mechanism and kinetic results of unactivated acids (KIE=1) are consistent with a light‐limited reaction.