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The concentration of harmful metal ions is growing globally, which raises the risk to both human and ecological health. The use of "adsorption" technique has been found to be very effective, for the removal of toxic metal ions. Among other things, hydrogels as an adsorbent work effectively for the removal of toxic metal ions and other aquatic pollutants. The newly designed potato starch‐xanthate (SX) based hydrogel (SX‐modified hydrogel) has been synthesized using a mixture of acrylamide (AAm) and acrylic acid (AA) monomers, with the help of free‐radical graft copolymerization technique. The synthesized SX‐modified hydrogel has been characterized by several analytical techniques, namely, UV–visible (UV–vis) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, gel permeation chromatography (GPC), thermogravimetric (TG) analysis, point of zero charge (ΔpHPZC) analysis, x‐ray diffraction (XRD) analysis, and scanning electron microscope (SEM) analysis. The main objective of the current work is to remove the Cu2+ and Co2+ ions from wastewater using SX‐modified hydrogel as well as to study the swelling and water retention properties of the SX‐modified hydrogel. The swelling ratio of SX‐modified hydrogel has been found to be 312.31, 374.01, and 410.20 g/g at optimum pH 10, temperature 35°C, time 675 min in gray wastewater, tap water, and distilled water, respectively. The maximum percentage removal of Cu2+ and Co2+ ions by SX‐modified hydrogel has been found as 97.7% and 94.2%, respectively, at optimum conditions. The Langmuir isotherm model fits best with the experimental data, with maximum adsorption capacity of 515.46 mg/g for Cu2+ and 483.09 mg/g for Co2+ ions, respectively. The kinetic studies suggest that the adsorption process is governed by the second order kinetic model with rate constant of 2.06 × 10−4 g/(mg min) for Cu2+ and 1.79 × 10−4 g/(mg min) for Co2+ ions, respectively. The negative ΔG values suggest the adsorption process is spontaneous in nature. In addition, the positive ΔH values support the adsorption process is endothermic in nature. The SX‐modified hydrogel showed a remarkable desorption efficiency with 96.7% for Cu2+ and 92.5% for Co2+ ions and reusability for four consecutive adsorption–desorption cycles. It can be concluded that the SX‐modified hydrogel has showed an effective, economical, easy, low energy consuming, and significant potential in the treatment of wastewater containing heavy metal ions. [ABSTRACT FROM AUTHOR]

Polypropylene (PP) is believed to be a rather promising cable insulating material for high‐capacity electric power system with low carbon emission due to its decent thermo‐resistance and recyclable nature. In this paper, a new dually chemical grafting modification strategy by methyl acrylate (MA) and acrylic acid (AA) is put forward to tailor the charge transportation behavior in PP, thus further enhancing the electrical properties. Experimental results indicate that the dually grafted PP with 2.3 weight percent (wt%) MA and 1.9 wt% AA shows enhanced volume resistivity and electrical breakdown strength than pure PP, and the space charge injection is significantly suppressed. This work further adopts thermally stimulated depolarization current (TSDC) test and computational analysis based on density functional theory (DFT) to reveal the mechanism of enhancement. The analysis shows that grafted chemical groups can introduce quantities of deep traps and electrostatic potential wells which are strongly correlated with the carbonyl group and would hinder the charge transportation thus improving the electrical insulating performances of PP. This work would provide a new route of PP‐based dually grafting modification for the development of high‐voltage cable insulation. [ABSTRACT FROM AUTHOR]

Magnetic superabsorbents have been successfully synthesized through aqueous solution polymerization, employing sodium alginate as the backbone material, acrylic acid and acrylamide as the polymeric monomers, Fe3O4 nano-particles as the magnetic component, N,N'-methylenebisacrylamide as the crosslinking agent, and ammonium persulfate serving as the initiator. The micro-morphology and thermal stability of these superabsorbents were thoroughly characterized using scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA), respectively. A comprehensive investigation was undertaken to examine the swelling capacity, water retention properties, magnetic responsiveness, and reusability of the magnetic superabsorbents. The findings reveal that these superabsorbents possess an impressive maximum water absorption capacity of 302.7 g/g in distilled water. Notably, their swelling ratios maintain high levels within a pH range of 5–10. Featuring a porous structure, the magnetic superabsorbents demonstrate rapid swelling kinetics, attaining swelling equilibrium within 30 min in a 1 wt% NaCl solution. Furthermore, the superabsorbents exhibit excellent magnetic responsiveness, characterized by a maximum saturation magnetization of 7.91 emu/g, allowing for swift separation under an external magnetic field. Lastly, the magnetic superabsorbents display outstanding reusability, with their water absorption capacity in distilled water still exceeding 90% of the initial swelling ratio after seven reuse cycles. [ABSTRACT FROM AUTHOR]

A convenient and general method for the construction of 2‐quinolinones was developed in this paper. The Pd‐catalyzed cyclization reaction of various o‐iodoanilines with acrylates or acrylic acids proceeded smoothly to produce 2‐quinolinones in 28–>99 % yields. The key to achieve the cyclization reaction is to utilize suitable base, such as potassium pivalate and potassium acetate. Various synthetically useful functional groups, such as halogen atoms, methoxycarbonyl, and nitro groups, remained intact during the reaction. The effects of catalyst and base on this cyclization reaction and kinetic experiments were investigated to understand the aspect of the reaction. [ABSTRACT FROM AUTHOR]

AbstractOwing to the low water-cement ratio (less than 0.25) of ultra-high-performance concrete (UHPC) materials, the system exhibits increased viscosity, diminished slurry flow, and challenges in pouring during the construction process, which compromise its workability. Consequently, the development of highly efficient viscosity-reducing polycarboxylate superplasticizer (PCE) is of paramount importance. In this study, we synthesized a series of viscosity-reducing polycarboxylate superplasticizers(JN-PCE) utilizing allyl polyethylene glycol ether (APEG), acrylic acid (AA), and sodium methallyl sulfonate (SMAS) as raw materials through the process of free radical polymerization. Fourier-transform infrared spectroscopy, nuclear magnetic resonance, gel permeation chromatography, and energy-dispersive X-ray spectroscopy were employed to characterize the materials. Subsequent evaluations of surface tension, fluidity, adsorption performance, and Marsh time demonstrated that these superplasticizers exhibited commendable dispersion and remarkable viscosity-reducing properties within a low water-cement ratio system. At a water-cement ratio of 0.18, the Marsh time of the JN-type PCE was reduced by 40% while maintaining the same fluidity, thereby underscoring the effective viscosity-reducing capabilities of the synthesized polycarboxylate superplasticizer. [ABSTRACT FROM AUTHOR]

Hydrogel‐based wearable strain sensors have recently gained considerable interest due to their promising applications in real‐time health monitoring and motion detection. However, achieving integrated high‐stretchability, self‐adhesiveness, and long‐term water‐retaining property simultaneously in hydrogel systems remains a big challenge, which limits their applications in wearable electronics. Herein, a multifunctional hydrogel material designed is proposed for wearable strain sensors that can be manufactured by digital light processing (DLP) 3D printing technology. By tailoring the composition of chemically cross‐linked networks (ploy(acrylamide)/poly(acrylic acid)/poly(ethylene glycol) diacrylate), physically cross‐linked networks (ploy(acrylamide)/poly(acrylic acid)/poly(ethylene glycol) diacrylate/silk fibroin/glycerol/water) and microstructures on the surface, the 3D printed hydrogel exhibits promising superior and adjustable mechanical properties, tunable adhesion and good water‐retaining property simultaneously. In addition, through adding conductive ions, high ionic conductivity can also be achieved for stretchable sensing applications. Based on these integrated multifunctionalities, the 3D printed hydrogel is suitable for wearable strain sensors to detect various body motions. This work provides a prospect for 3D printable hydrogel systems with broad applications in wearable electronics. [ABSTRACT FROM AUTHOR]

Magnetic superabsorbents have been successfully synthesized through aqueous solution polymerization, employing sodium alginate as the backbone material, acrylic acid and acrylamide as the polymeric monomers, Fe3O4 nano-particles as the magnetic component, N,N'-methylenebisacrylamide as the crosslinking agent, and ammonium persulfate serving as the initiator. The micro-morphology and thermal stability of these superabsorbents were thoroughly characterized using scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA), respectively. A comprehensive investigation was undertaken to examine the swelling capacity, water retention properties, magnetic responsiveness, and reusability of the magnetic superabsorbents. The findings reveal that these superabsorbents possess an impressive maximum water absorption capacity of 302.7 g/g in distilled water. Notably, their swelling ratios maintain high levels within a pH range of 5–10. Featuring a porous structure, the magnetic superabsorbents demonstrate rapid swelling kinetics, attaining swelling equilibrium within 30 min in a 1 wt% NaCl solution. Furthermore, the superabsorbents exhibit excellent magnetic responsiveness, characterized by a maximum saturation magnetization of 7.91 emu/g, allowing for swift separation under an external magnetic field. Lastly, the magnetic superabsorbents display outstanding reusability, with their water absorption capacity in distilled water still exceeding 90% of the initial swelling ratio after seven reuse cycles. [ABSTRACT FROM AUTHOR]

Garnet‐type solid‐state electrolytes (SSEs) exemplified by Li6.5La3Zr1.5Ta0.5O12 (LLZT) are chemically unstable when exposed to air, leading to the formation of impurities and poor wettability with Li metal. Herein, a protocol to address this Li/LLZT interface challenge is demonstrated by constructing a lithiophilic MgF2 nanofilm on the LLZT pellet. Specifically, a solution‐based process is developed for the surface engineering of LLZT, utilizing magnesium trifluoroacetate (MTF) as the molecular precursor while poly(acrylic acid) (PAA) as the coordinating agent in a sol‐gel process. It is demonstrated that a facile spin‐coating treatment followed by high‐temperature annealing reliably forms crack‐free MgF2 nanofilms with precise thickness control. Introduction an MgF2 interlayer transforms the LLZT pellet into a highly lithophilic, facilitating close contact with the lithium anode, thereby leading to a significantly reduced interfacial resistance from 1190 Ω cm2 to 6 Ω cm2. Such an interfacial engineering enables stable cycling of full batteries with high reversibility and rate capability using commercial LiFePO4 and LiNi0.83Co0.07Mn0.1O2 as cathodes. This study unfolds the possibility of a solution‐based method as a facile and scalable process for the construction of fluoride nanofilms, which is promising to address the critical interfacial challenges of solid‐state batteries (SSBs) to facilitate its practical applications. [ABSTRACT FROM AUTHOR]

Using acrylic acid advanced ester and styrene as raw materials, the long-chain polyester polymer, polyacrylic acid advanced ester-styrene pour point depressant (P-PPD), was synthesized by molecular design, and its structure was characterized by infrared spectroscopy and nuclear magnetic resonance. In addition, this study experimentally investigated the effect of P-PPD on the phase equilibrium and induction time of natural gas hydrate inhibitors in deionized water (DW) and crude oil/water (O/W) systems, respectively. Polyvinylpyrrolidone (PVP) and mono ethylene glycol (EG) were selected as representatives of kinetic hydrate inhibitor (KHIs) and thermodynamic hydrate inhibitor (THIs), respectively. The results exhibit that P-PPD played a sight role in the phase equilibrium of hydrate, while the addition of P-PPD significantly prolonged the induction time of methane hydrate both in O/W + PVP, OW + EG and O/W + PVP + EG system, indicating that the addition of as-synthesized PPD has a synergistic inhibition effect on the nucleation ability of methane hydrate and can prevent hydrate from formatting during oil and gas transport process, and thus guarantee the flow assurance. The findings of this work will provide a data reference for the hybrid use of hydrate inhibitors and pour point depressants in oil and gas transport. [ABSTRACT FROM AUTHOR]

This study aims to synthesize and characterize a sulfated‐starch‐based superabsorbent polymer (S‐SAP). The S‐SAP is prepared by grafting 2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid (AMPS) and acrylic acid (AA) onto sulfated starch, which is subsequently crosslinked using N,N‐methylene‐bis‐acrylamide (MBA) via free radical polymerization with ammonium persulfate as the initiator. The successful grafting of AA and AMPS onto the starch backbone improves the thermal stability and increases the swelling capacity of the polymer. The swelling capacity and reusability of the S‐SAP are compared with those of commercial superabsorbent polymers (C‐SAPs). The swelling capacity of the S‐SAP is higher than those of C‐SAPs, reaching 417 g g−1 in distilled water and 47 g g−1 in a 0.15 M NaCl solution. The water absorption kinetics of the S‐SAP shows a good fit with the pseudo‐second‐order model. The polymer prepared herein has potential applications in horticulture and agriculture. [ABSTRACT FROM AUTHOR]

ABSTRACT The design of super‐antimicrobially active multipurpose nanocarriers as polymeric nanocomposites embedded with metal oxides with sustained drug release is beneficial in medical treatment for controlling inflammation and targeting a wide range of pathogenic microorganisms. Brilliant metal oxide nanoparticles (MOx) involving selenium dioxide, titanium dioxide, and vanadium pentoxide were well prepared in good yields, and their morphologies and structures were specified. Then they were embedded in copolymeric nanocomposites through in situ microemulsion polymerization of (E)‐2‐cyano‐N‐cyclohexyl‐3‐(dimethylamino)acrylamide (CHAA) with methyl methacrylate (MMA), dimethylaminoethyl methacrylate (DMAEMA), and acrylic acid (AA). In addition, ibuprofen was then loaded into the synthesized polymers and their nanocomposites to achieve high drug entrapment efficiency EE%, and its release behavior was studied in various simulated fluids. The produced drug‐loaded polymers and their nanocomposites were characterized using Fourier‐transform infrared spectroscopy (FT‐IR), transmission electron microscope (TEM), X‐ray diffraction (XRD), and thermogravimetric analysis (TG). Well‐defined nanospheres of polymeric‐metal oxide nanocomposites were generated in a size range of 50 nm, with ibuprofen loaded at a high encapsulation efficiency of approximately 97%. In vitro drug release was inspected for the polymer and its nanocomposites revealing that the presence of metal oxide nanoparticles resulted in prolonged and sustained release behavior for wound dressing. The antimicrobial study based on the zone of inhibition against various pathogenic microorganisms showed excellent activity against Bacillus cereus, Staphylococcus aureus, Escherichia coli, Helicobacter pylori, and Candida albicans. These findings validate the potential of these nanocomposites to serve as a viable upcoming antimicrobial agent for the treatment of human ailments. [ABSTRACT FROM AUTHOR]

To evaluate the mechanical properties, fluoride release, radiopacity, and setting characteristics of dental cements derived from highly reactive ionomer glasses and bottle glass mixtures. Two highly reactive glass series, LG99 and LG117, were synthesized, milled, sieved, and characterized using XRD and laser particle size analysis. These glasses were mixed with predetermined ratios of ground bottle glass, poly(acrylic acid), and aqueous tartaric acid to form glass ionomer cements. The cements' working time (WT), setting time (ST), fluoride release, radiopacity, compressive strength (CS), and elastic modulus (EM) were evaluated. Mean differences in CS were analyzed using multivariate ANOVA with Tukey's post hoc test at p = 0.05. The WT and ST for both groups ranged from 1.5 to 2.5 min. LG99 series cements showed significantly higher CS (∼65 MPa) and EM (∼2 GPa) than LG117 series (p < 0.05). Both series showed similar fluoride release profiles, peaking at 1.2 mmol/L at 28 days. Radiopacity for LG99 ranged from 0.97 to 1.34, while LG117 ranged from 0.60 to 0.95. Solid state 27Al magic-angle spinning-nuclear magnetic resonance (MAS NMR) confirmed the presence of Al(IV) and Al(VI), indicating setting completion by one day for both series. Bottle glass showed a chemical shift at 55.8 ppm, overlapping with LG99′s Al(IV) signal. The 19F MAS NMR spectra revealed Al-F and F-Sr(n) species in all glasses, with LG117 forming CaF 2 after one day in deionized water. Mixtures of highly reactive ionomer glass and bottle glass produced cements with satisfactory properties for dental applications. Further research is needed to optimize their formulation and properties. [ABSTRACT FROM AUTHOR]

This paper reports on the novel composite membrane electrolytes used in Zn/MnO2, Al/MnO2, Al/air, and zinc/air electrochemical devices. The composite membranes were made using poly(vinyl alcohol), poly(acrylic acid), and a sulfonated polypropylene/polyethylene separator to enhance the electrochemical characteristics and dimensional stability of the solid electrolyte membranes. The ionic conductivity was improved significantly by the amount of acrylic acid incorporated into the polymer systems. In general, the ionic conductivity was also enhanced gradually as the testing temperature increased from 20 to 80 °C. Porous zinc gel electrodes and pure aluminum plates were used as the anodes, while porous carbon air electrodes or porous MnO2 electrodes were used as the cathodes. The cyclic voltammetry properties and electrochemical impedance characteristics were investigated to evaluate the cell behavior and electrochemical properties of these prototype cells. The results showed that these prototype cells had a low bulk resistance, a high cell power density, and a unique device stability. The Al/MnO2 cell achieved a density of 110 mW cm−2 at the designated current density for the discharge tests, while the other cells also exhibited good values in the range of 70–100 mW cm−2. Furthermore, the Zn/air cell consisting of the PVA/PAA = 10:5 composite membrane revealed an excellent discharge capacity of 1507 mAh. This represented a very high anode utilization of 95.7% at the C/10 rate. [ABSTRACT FROM AUTHOR]

Weak polyelectrolyte chains are versatile polymeric materials due to the large number of functional groups that can be used in different environmental applications. Herein, one weak polycation (polyethyleneimine, PEI) and two polyanions (poly(acrylic acid), PAA, and poly(sodium methacrylate), PMAA) were directly deposited through precipitation of an inter-polyelectrolyte coacervate onto the silica surface (IS), followed by glutaraldehyde (GA) crosslinking and extraction of polyanions chains. Four core–shell composites based on silica were synthesized and tested for adsorption of lead (Pb2+) and nickel (Ni2+) as model pollutants in batch sorption experiments on the laboratory scale. The sorbed/desorbed amounts depended on the crosslinking degree of the composite shell, as well as on the type of anionic polyelectrolyte. After multiple loading/release cycles of the heavy metal ions, the maximum sorption capacities were situated between 5–10 mg Pb2+/g composite and 1–6 mg Ni2+/g composite. The strong crosslinked composites (r = 1.0) exhibited higher amounts of heavy metal ions (Me2+) sorbed than the less crosslinked ones, with less PEI on the surface but with more flexible chains being more efficient than more PEI with less flexible chains. Core–shell composites based on silica and weak polyelectrolytes could act as sorbent materials, which may be used in water or wastewater treatment. [ABSTRACT FROM AUTHOR]

Nitrogen (N) losses from conventional N fertilizers contribute to environmental degradation and low N use efficiency. Highlighting the need for slow-release fertilizers (SRFs) to mitigate these problems, this study aims to develop slow-release N fertilizers using starch-grafted-poly[(acrylic acid)-co-acrylamide] based nanoclay polymer composites (NCPCs) and investigate their efficacy for slow N delivery in soil. Three types of NCPCs, NCPC(A) (poly [(acrylic acid)-co-acrylamide]), NCPC(W) (wheat starch-grafted-poly[(acrylic acid)-co-acrylamide), and NCPC(M) (maize starch-grafted-poly[(acrylic acid)-co-acrylamide) were prepared and characterized using FTIR spectroscopy and X-ray diffraction techniques. N-release behaviour of the products was assessed under two distinct soils, i.e., Assam (Typic Hapludults, pH 4.2) and Delhi (Typic Haplustepts, pH 7.9) soils. Additionally, the effects of varying soil moisture and temperature levels on N release were studied in the Assam soil. The N-release kinetics of the synthesized fertilizers were assessed using zero-order, first-order, Higuchi, and Korsmeyer−Peppas models. Degradability of the NCPCs was evaluated by measuring evolved CO2–C under various soil conditions as an indicator of microbial degradation. The results indicated that NCPC fertilizers significantly slowed down the release of N compared to urea. According to the R2 values obtained, it was evident that the first-order kinetic model most accurately describes the N release from both urea and NCPC-based N fertilizers in the studied soils. Among the formulations, NCPC(A) exhibited the lowest N release (42.94–53.76%), followed by NCPC(M) (51.05–61.70%), NCPC(W) (54.86–67.75%), and urea (74.33–84.27%) after 21 days of incubation. The rate of N release was lower in the Assam soil compared to the Delhi soil, with higher soil moisture and temperature levels accelerating the release. Starch addition improved the biodegradability of the NCPCs, with NCPC(W) showing the highest cumulative CO2-C evolution (18.18–22.62 mg g−1), followed by NCPC(M) (15.54–20.97 mg g−1) and NCPC(A) (10.89–19.53 mg g−1). In conclusion, NCPC-based slow-release fertilizers demonstrated a more gradual N release compared to conventional urea and the inclusion of starch enhanced their degradability in the soil, which confirms their potential for sustainable agricultural applications. However, soil properties and environmental factors influenced the N release and degradation rates of NCPCs. [ABSTRACT FROM AUTHOR]

Background: Allergic rhinitis is a common inflammatory condition of the nasal mucosa that imposes a considerable health burden. Air pollution has been observed to increase the risk of developing allergic rhinitis. We addressed the hypotheses that early life exposure to air toxics is associated with developing allergic rhinitis, and that these effects are mediated by DNA methylation and gene expression in the nasal mucosa. Methods: In a case–control cohort of 505 participants, we geocoded participants' early life exposure to air toxics using data from the US Environmental Protection Agency, assessed physician diagnosis of allergic rhinitis by questionnaire, and collected nasal brushings for whole‐genome DNA methylation and transcriptome profiling. We then performed a series of analyses including differential expression, Mendelian randomization, and causal mediation analyses to characterize relationships between early life air toxics, nasal DNA methylation, nasal gene expression, and allergic rhinitis. Results: Among the 505 participants, 275 had allergic rhinitis. The mean age of the participants was 16.4 years (standard deviation = 9.5 years). Early life exposure to air toxics such as acrylic acid, phosphine, antimony compounds, and benzyl chloride was associated with developing allergic rhinitis. These air toxics exerted their effects by altering the nasal DNA methylation and nasal gene expression levels of genes involved in respiratory ciliary function, mast cell activation, pro‐inflammatory TGF‐β1 signaling, and the regulation of myeloid immune cell function. Conclusions: Our results expand the range of air pollutants implicated in allergic rhinitis and shed light on their underlying biological mechanisms in nasal mucosa. [ABSTRACT FROM AUTHOR]

In this work, Gum ghatti-cl-poly(acrylic acid)/CoFe2O4 (GGAACF) hydrogels were synthesized using a free radical polymerization technique, with CoFe2O4 nanoparticles incorporated via a co-precipitation method using nitrates as precursors. Thermal gravimetric analysis (TGA) revealed that the inclusion of CoFe2O4 nanoparticles enhanced the thermal stability of the hydrogels. Swelling studies indicated that the addition of 30 mg of CoFe2O4 nanoparticles maximized water retention. Rheological assessments demonstrated non-Newtonian behavior, with flow curves fitted best by the Power Law model. The incorporation of CoFe2O4 nanoparticles significantly improved the hydrogel's elasticity and viscosity, as evidenced by a higher storage modulus (G′) compared to the loss modulus (G″) across all frequencies, indicating the elastic nature of the hydrogels. The decrease in complex viscosity with increasing frequency confirmed the pseudoplastic properties of the hydrogels, attributed to the random alignment of CoFe2O4 nanoparticles within the matrix. Tan δ values were below unity at all tested frequencies, underscoring the hydrogels' strong elastic properties. These findings highlight the effectiveness of rheological analysis in characterizing the viscoelastic behavior of polymer hydrogels, which can be tailored for various applications. [ABSTRACT FROM AUTHOR]

A cellulose nanofiber-reinforced starch-graft-poly(acrylic acid) (St-g-P(AA)) nanocomposite hydrogel was developed as a bioadsorbent to remove chromium ions [Cr(VI)] using a fix-bed adsorption column. The influence of several factors on adsorption column efficiency was investigated in this study, including pH, initial concentration of Cr(VI) ions, and solution input flow rate. Following the first study, the appropriate pH, initial concentration, and flow rate ranges were determined to be 4–6, 20–60 mg/L, and 5–15 mL/min, respectively. The surface response approach based on the Box–Behnken model was used to statistically examine the influence of each independent parameter on response performance (removal efficiency) and anticipate the optimal result. The findings showed that the pH of the solution had the most significant impact. The maximum removal efficiency of the nanocomposite hydrogel was %50.26 at pH = 6, an initial concentration of 20 mg/L, and a flow velocity of 10 mL/min. The Langmuir isotherm model successfully matched the results, and the maximum adsorption capacity was calculated to be 23.47 mg/g. [ABSTRACT FROM AUTHOR]

A reversible associated copolymer capable of healing at room temperature was constructed using acrylic acid (AA) and hemin as anionic monomers, and methacryloyloxyethyl trimethylammonium chloride (DMC) as the cationic monomer. Through optimization of the synthesis conditions, characterization by 1HNMR, infrared spectroscopy, ultraviolet-visible spectroscopy, Thermogravimetric analysis, differential scanning calorimetry, and construction of reasonable models for dynamic simulation, the following conclusions were obtained: The introduction of Hemin could convert light energy into heat energy, accelerating the healing of damaged areas; the predicted glass transition temperature value matched well with the experimental value, demonstrating the reliability of the constructed polymer model; the cohesive energy density (CED), dominated by electrostatic interactions, was identified as the key factor in the self-healing mechanism; the study also visually captured the microscopic process of self-healing within the polymer, providing a detailed understanding of the molecular rearrangements that facilitate this process. This work offers valuable insights into the design of reversible associated polymers, contributing to the broader goal of developing functional polymer materials aligned with circular economy principles. [ABSTRACT FROM AUTHOR]

In this study, we are interested in preparing novel hydrogel and hydrogel nanocomposite-based adsorbents for removing methylene blue (MB) dye based on grafted locust bean gum (LBG). LBG hydrogel and hydrogel nanocomposite were synthesized using a radical polymerization technique in the absence and presence of TiO2 with LBG-cl-(acrylic acid (AA)-co-acrylamide (AAm)). Various analytical instruments Fourier transform infrared (FTIR), X-Ray diffraction (XRD), Scanning electron microscopy (SEM), and High-resolution transmission electron microscopy (HRTEM) were used to elucidate the chemical structure and surface morphology of the prepared samples. Using a batch adsorption experiment, the Langmuir isotherm model showed that LBG-cl-p(AA-co-AAm) hydrogel had a maximum adsorption capacity of 1540.9 mg/g and LBG-cl-(AA-co-AAm)/TiO2 hydrogel nanocomposites had a maximum adsorption capacity of 1273.4 mg/g at neutral pH. The thermodynamic data demonstrated that MB dye was removed via spontaneous adsorption. Furthermore, the regeneration study showed good recyclability for the obtained hydrogel nanocomposites through six consecutive reusable cycles. Therefore, the hydrogel nanocomposites are an effective adsorbent for the removal of MB dye from aqueous solutions. [ABSTRACT FROM AUTHOR]

Assembly of two-dimensional (2D) nanomaterials into well-organized architectures is pivotal for controlling their function and enhancing performance. As a promising class of 2D nanomaterials, MXenes have attracted significant interest for use in wearable electronics due to their unique electrical and mechanical properties. However, facile approaches for fabricating MXenes into macroscopic fibers with controllable structures are limited. In this study, we present a strategy for easily spinning MXene fibers by incorporating polyanions. The introduction of poly(acrylic acid) (PAA) into MXene colloids has been found to alter MXene aggregation behavior, resulting in a reduced concentration threshold for lyotropic liquid crystal phase. This modification also enhances the viscosity and shear sensitivity of MXene colloids. Consequently, we were able to draw continuous fibers directly from the gel of MXene aggregated with PAA. These fibers exhibit homogeneous diameter and high alignment of MXene nanosheets, attributed to the shear-induced long-range order of the liquid crystal phase. Furthermore, we demonstrate proof-of-concept applications of the ordered MXene fibers, including textile-based supercapacitor, sensor and electrical thermal management, highlighting their great potential applied in wearable electronics. This work provides a guideline for processing 2D materials into controllable hierarchical structures by regulating aggregation behavior through the addition of ionic polymers. [ABSTRACT FROM AUTHOR]

The interaction of a sensitive oxide with a target gas determines its chemiresistive signal; however, the lack of a fundamental theoretical model currently hinders its wide application. In this work, CuScO2 microsheets are synthesized by a simple hydrothermal method, which brings about the first oxide-based acrylic acid gas sensor. It exhibits high selectivity for acrylic acid, outperforming other volatile organic compound (VOC) gases, including methanol, ethanol, formaldehyde, toluene, acetonitrile, and acetone, with a high response (up to 7–10 ppm acrylic acid) and an ultralow detection limit down to sub-ppm level (14 ppb) at a low operating temperature of 160°C. Compared to the chromatographic techniques, the proposed CuScO2 gas sensor represents a prominent chemiresistive effect favorable for the simple and efficient monitoring of acrylic acid gas, which is significant for human health. In addition, the remarkable gas sensing properties of CuScO2 are elucidated by a new mechanism based on the results of microstructural characterization and first-principles calculations followed by energy band analysis. Instead of the classic ambient oxygen ionosorption, Cu and Sc atoms on the solid surface play the crucial roles in target gas adsorption and electron transfer procedures, respectively. Such synergistic effect of metal atoms offers a new perspective for the design of material systems for advanced gas sensing devices. [ABSTRACT FROM AUTHOR]

As a promising energy‐saving technology, electrochromic technology has been widely investigated for practical applications. However, there is relatively few research about the applications under certain extreme climatic conditions since gel electrolytes often occur freezing and volatilizing. In this work, a poly(vinyl alcohol)/poly(acrylic acid) (PVA/PAA) gel electrolyte with good anti‐freezing and heat‐resistance performance is developed. Utilizing hydrated tungsten oxide (WO3·xH2O) and polyaniline (PANI) as electrochromic materials and the PVA/PAA gel as electrolyte, a WO3·xH2O/PVA/PAA‐ethylene glycol (EG)‐H2O/PANI electrochromic device (WO3·xH2O/PAEH/PANI ECD) is obtained, which can work efficiently at wide operating temperatures from −20 to 60 °C. The device has multiple reversible color changes, a large optical modulation of 66.2% at 600 nm, high coloration efficiency of 386.0 cm2 C−1, fast responses (with coloration/bleaching times of 1.3/1.1 s), as well as excellent cyclic stability (82.0% of the initial optical modulation is still retained after 2100 cycles). This work reveals the potential application prospects of PAEH gel electrolyte in practical extreme operating conditions. [ABSTRACT FROM AUTHOR]

The design and fabrication of novel soft bioelectronic materials for rapid wound healing and real‐time monitoring are critical for smart healthcare. However, developing such integrated multifunctional materials devices remains challenging due to fabrication dynamics and sensing interface issues. Herein, a novel strategy is presented for accelerating the kinetics of hydrogels integrating antimicrobial, electrotherapeutic, and wound monitoring functions via bimetallic phenolic networks. The Al3+ catalyzes the radical copolymerization reaction of acrylic acid, resulting in the gelation of the system within 10 s, and also catalyzes the redox reaction between silver and lignin, inducing the sustained release of catechol, which significantly enhances the hydrogel's antimicrobial activity and shortened the wound healing process. Meanwhile, the abundant non‐covalent interactions enhance the hydrogel's tissue adhesion, and mechanical properties (tensile strength 1.558 MPa and elongation 1563%). In addition, the bimetallic ions endow the hydrogels with excellent sensing properties. Under the synergy of electrical stimulation, the wound healing rate is accelerated. Notably, wound assessment can be performed by monitoring changes in electrical signals over the wound, which can assist physicians and patients in achieving intelligent wound management. This work provides new insights into the design and application of multifunctional smart bioelectronic materials. [ABSTRACT FROM AUTHOR]

Electrochemical Performance of aqueous Zn‐ion batteries (AZIBs) is prominently constrained by poor stability of zinc‐metal anodes. However, the use of conventional aqueous separators unfavorable to the uniform deposition of Zn metal and restricted cell cycle life, has hindered the large‐scale application of such battery systems. Here, a separator with hydrophobic/hydrophilic structural domains (marked as PP‐g‐AA) is reported, where the polypropylene (PP) polymer backbone permits partial blockage of water molecules and prevent side reactions, and the carboxyl functional groups in the grafted acrylic acid (AA) facilitate to well regulate the interfacial electric field and Zn2+ ion concentration field, thus remarkably promotes homogenization of zinc ion flux, achieving dendritic‐free deposition of Zn2+. Moreover, the PP‐g‐AA separator sustains a long‐term cycling over 4000 h at a current density of 2 mA cm−2 with a high Coulombic efficiency of 99.6% achieved in Zn||Cu cells, which if assembled into Zn||Zn0.27V2O5·nH2O (ZVO) cells would yield ≈100% retention for 1000 cycles. This research highlights that the strategy opens up a new avenue based on PP‐g‐AA for further decreasing the cost and promoting the industrial application of AZIBs. [ABSTRACT FROM AUTHOR]

Since the advent of 3D printing technology, a significant effort has been made to develop new 3D printable materials. Despite the recent progress in the field of 3D printing, the limited availability of photoactive resins has motivated continuous research endeavors to develop novel photoresins with multifunctional capabilities. Herein a biobased photoresin derived is reported from modified olive oil, designed for high‐resolution solvent‐free 4D printing with multifunctional capabilities. The physicochemical properties of the printed polymers are fine‐tuned using acrylic acid as a diluent cum comonomer. The mechanical properties of the printed polymers are similar to various soft tissues, such as ligaments, articular cartilage, and soft collagenous bone, showcasing its potential for soft tissue engineering applications. While the excellent temperature‐responsive shape memory 4D attributes coupled with exceptional antimicrobial properties toward gram‐negative and gram‐positive bacteria highlight the multifunctional nature of the printed polymers. Moreover, the printed polymers exhibited outstanding hemocompatibility and good cytocompatibility toward mouse fibroblast cells, suggesting their potential soft tissue engineering applications. In sum, the newly developed biobased resin can be employed to minimize the environmental impact of additive manufacturing while being competitive with existing fossil‐based photoresins, thereby meeting the growing demand for advanced photoresins with superior high‐resolution printing and smart properties for biomedical applications. [ABSTRACT FROM AUTHOR]

Hydrogels have emerged as promising candidates for biomedical applications, such as replacing natural articular cartilage, owing to their unique viscoelastic properties. However, sufficient mechanical properties, self‐healing ability, and adhesive nature are some issues limiting its application window. Here, a facile one‐pot synthesis of dual cross‐linked zinc‐coordinated copolymer hydrogels is presented. The network structure of the copolymer hydrogels is strategically developed via dynamic and reversible physical cross‐linking by Zn2+ ions and simultaneous covalent cross‐linking through a covalent cross‐linker viz methylene bisacrylamide. Fourier‐transform infrared (FTIR), X‐ray diffraction (XRD) scanning electron microscopy (SEM), and Brunauer–Emmett–Teller (BET) analysis have thoroughly characterized the structure of the synthesized hydrogels. The introduction of Zn2+ offers dynamic and reversible complexation, leading to excellent mechanical properties and self‐healing features. Moreover, the percentage of the equilibrium water content of zinc‐coordinated copolymer hydrogel samples is comparable with that of natural articular cartilage. The Shear sliding study shows the dominant adhesive behavior of HGel‐Zn(NO3)2 sample compared to the parent HGel sample. This facile dual cross‐linked hydrogel, HGel‐Zn(NO3)2, with a combination of good mechanical properties, efficient self‐recovery, adequate water content, and favorable adhesive nature, seems very promising to mimic the articular cartilage. [ABSTRACT FROM AUTHOR]

Diversity in solvent selection bestows the organic gel with appealing characteristics embracing antidrying, anti‐icing, and antifouling abilities. However, organic gel, subjected to the "toxic" inherent property of solvent, is not able to be manipulated on skin. Herein, introducing the hydrogel layer amid organic gel and skin is envisaged to realize application of organic gel on skin. Hydrogel, inserted as the medium layer, works for the coupling role between skin and organic gel, also avoids the direct contact of organic gel toward skin. First, hydrogel system composed of acrylic acid is fabricated, meanwhile organic gel is prepared employing 2‐hydroxyethyl methacrylate, ethylene glycol (EG) as solvent. Organic gel is able to adhere to hydrogel by hydrogen bonding resulting from carboxyl groups of polyacrylic acid chains and hydroxyl groups occurring on 2‐hydroxyethyl methacrylate or EG. Additionally, hydrogen bonding enables the hydrogel to be firmly attached to skin, thus organic gel/hydrogel/skin assembly is produced. The further application of organic gel is exploited by incorporating stimuli‐responsive dyes including spiropyran and rhodamine derivative. [ABSTRACT FROM AUTHOR]

[Display omitted] Understanding polyelectrolyte complexation remains limited due to the absence of a systematic methodology for analyzing the distribution of components between the polyelectrolyte complex (PEC) and the dilute phases. We developed a methodology based on NMR to quantify all components of solid-like PECs and their supernatant phases formed by mixing different ratios of poly(allylamine hydrochloride) (PAH) and poly(acrylic acid)-sodium salt (PAA). This approach allowed for determining relative and absolute concentrations of polyelectrolytes in both phases by 1H NMR studies. Using 23Na and 35Cl NMR spectroscopy we measured the concentration of counterions in both phases. Regardless of the mixing ratio of the polyelectrolytes the PEC is charge-stoichiometric, and any excess polyelectrolytes to achieve charge stoichiometry remains in the supernatant phase. The majority of counterions were found in the supernatant phase, confirming counterion release being a major thermodynamic driving force for PEC formation. The counterion concentrations in the PEC phase were approximately twice as high as in the supernatant phase. The complete mass balance of PEC formation could be determined and translated into a molecular picture. It appears that PAH is fully charged, while PAA is more protonated, so less charged, and some 10% extrinsic PAH-Cl- pairs are present in the complex. [ABSTRACT FROM AUTHOR]

AbstractThe Guar Gum Xanthate based hydrogel GGmX-g-poly(AA-co-HEMA) has been successfully synthesized by using the graft copolymerization of two monomers, acrylic acid (AA) and 2-hydroxyethyl methacrylate (HEMA) hydrogel. The synthesis follows the free-radical graft polymerization method. UV-visible spectroscopy (UV), Thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), Point zero charge (PZC), and field emission scanning electron microscopy (FESEM) were employed for the characterization of the synthesized hydrogel. This hydrogel has shown a high swelling ratio of 430.2 g/g and retention of 75.82% in distilled water which is a notable result. By using GGmX-g-poly(AA-co-HEMA) hydrogel, the maximum percentage of heavy metal ions removal from wastewater was found to be 98.5(±1.5)% and 97.1(±1.5) at optimum pH 6 and 6.5 for Cu2+ and Ni2+ solutions respectively. The Langmuir adsorption isotherm fits best for the adsorption data indicating a monolayer adsorption with maximum adsorption capacity of 423.72 (±26.1) mg/g and 404.85 (±31.4) mg/g for Cu2+ and Ni2+ ions respectively. The pseudo-second-order kinetic model provides the most accurate depiction of adsorption kinetics with rate constant 9.1 × 10−4 (±1.37×10−4)g/(mg.min) for Cu2+ and 8.3 × 10−4 (±1.24×10−4)g/(mg.min) for Ni2+ ions, respectively. The negative ΔG value (-4.75 kJ/mol for Cu2+ and −3.26 kJ/mol for Ni2+ ions) and positive value of ΔH (57.55 (±5.41) kJ/mol for Cu2+ and 40.60(±5.37) kJ/mol for Ni2+ ions) suggested the process to be spontaneous, endothermic, and feasible. It has been found that the hydrogel has excellent regenerative capacity with the % adsorption has been found to be 84.8% for Cu2+ and 82.4% for Ni2+ ions for the fifth cycle. [ABSTRACT FROM AUTHOR]

Traditional adhesive hydrogels perform well in tissue adhesion but they fail to prevent postoperative tissue adhesion. To address this challenge, a biodegradable Janus adhesive hydrogel (J-AH) was designed and fabricated by the assembly of three different functional layers including anti-adhesive layer, reinforceable layer, and wet tissue adhesive layer. Each layer of J-AH serves a specific function: the top zwitterionic polymeric anti-adhesive layer shows superior resistance to cell/protein and tissue adhesion; the middle poly(vinyl alcohol)/tannic acid reinforceable matrix layer endows the hydrogel with good mechanical toughness of ∼2.700 MJ/m3; the bottom poly(acrylic acid)/polyethyleneimine adhesive layer imparts tough adhesion (∼382.93 J/m2 of interfacial toughness) to wet tissues. In the rat liver and femoral injury models, J-AH could firmly adhere to the bleeding tissues to seal the wounds and exhibit impressive hemostatic efficiency. Moreover, in the in vivo adhesion/anti-adhesion assay of J-AH between the defected cecum and peritoneal walls, the top anti-adhesive layer can effectively inhibit undesired postoperative abdominal adhesion and inflammatory reaction. Therefore, this research may present a new strategy for the design of advanced bio-absorbable Janus adhesive hydrogels with multi-functions including tissue adhesion, anti-postoperative adhesion and biodegradation. Despite many adhesive hydrogels with tough tissue adhesion capability have been reported, their proclivity for undesired postoperative adhesion remains a serious problem. The postoperative adhesion may lead to major complications and even endanger the lives of patients. The injectable hydrogels can cover the irregular wound and suppress the formation of postoperative adhesion. However, due to the lack of adhesive properties with tissue, it is difficult for the hydrogels to maintain on the wound surface, resulting in poor anti-postoperative adhesion effect. Herein, we design a Janus adhesive hydrogel (J-AH). J-AH integrates together robust wet tissue adhesion and anti-postoperative adhesion. Therefore, this research may present a new strategy for the design of advanced bio-absorbable Janus adhesive hydrogels. [Display omitted] [ABSTRACT FROM AUTHOR]

ABSTRACT A copper‐based one‐dimensional framework compound [Cu2(L1)4(L2)]n (1) [L1 = 3‐(2‐thienyl)acrylic acid, L2 = 4,4′‐bipyridine] has been synthesized by slow diffusion of layers technique and characterized by spectroscopic methods and single‐crystal X‐ray crystallography. X‐ray diffraction analysis reveals that the compound is crystallized in the triclinic crystal system with space group Pī. Two neighboring Cu centers are bridged by four carboxylato groups from four different L1 ligands, leading to the formation of a paddle‐wheel [Cu2(COO−)4] secondary building unit (SBU). The paddle‐wheel units are interconnected by bidentate 4,4′‐bipyridine ligands to form a one‐dimensional infinite chain network. In [Cu2(L1)4(L2)]n (1), Cu(II) ion features a penta‐coordinated environment around it. Notably, [Cu2(L1)4(L2)]n (1) is capable of activating molecular oxygen to efficiently catalyze the oxidation of alcohols under base‐free conditions. [ABSTRACT FROM AUTHOR]

Thermochromic smart windows have been widely developed for solar regulation to save building energy. However, most current smart windows still exhibit a single responsiveness to a specific temperature, which is not conducive to daytime energy saving or nighttime privacy protection. Herein, a low‐temperature response is achieved by pre‐initiation of the monomer acrylamide (AAm) and acrylic acid (AA) in the synthesis of P(AAm‐co‐AA). Then, N‐isopropyl acrylamide and AAm are introduced into P(AAm‐co‐AA) to form a pre‐polymerized precursor solution. The liquid precursor solution can be encapsulated within two quartz glasses and synthesized in situ to prepare smart windows, which exhibit a high visible light transmittance of 84.4%, excellent solar modulation of 69.5%, and bidirectional temperature responsiveness (cold and hot). In addition, the upper critical solution temperature and the lower critical solution temperature of the hydrogel and the light transmission interval between the two temperatures can be flexibly adjusted to adapt to different climates and individual user needs. The designed smart window maintains a high light transmission within the human body's comfort temperature range. The bidirectional temperature response window achieves the dual functions of energy saving and privacy protection, making it an ideal smart window candidate with good prospects for practical applications. [ABSTRACT FROM AUTHOR]

In this study, water‐based pressure‐sensitive adhesives (PSAs) were synthesized through an emulsion polymerization process using n‐butyl acrylate, methacrylic acid, acrylic acid, and N‐vinylpyrrolidone monomers, in combination with anionic and non‐ionic surfactants. The PSA was coated onto the corona‐treated surface of a BOPP film using a Mayer bar to prepare packaging tape. The effect of surfactant concentration on the properties of the resulting copolymer and PSA was investigated. The chemical structure, component distribution, and thermal behavior of the copolymer were analyzed using FTIR, HPLC, and DSC. The physical properties of the synthesized copolymer, such as solid content, viscosity, particle size, and gel content, were also determined. The performance of the prepared packaging tapes was evaluated through loop tack, 180° peel, and holding shear time tests. The results indicated that surfactant concentration significantly affected the adhesive's performance. Notably, the use of a 2.5 wt% surfactant mixture yielded promising results, with high monomer conversions and excellent adhesion properties in the tape. [ABSTRACT FROM AUTHOR]

We report vitrimer-like elastomers that exhibit significantly fast stress relaxation using carboxy exchange via the conjugate substitution reaction of α-(acyloxymethyl) acrylate skeletons. This network design is inspired by a small-molecule model that shows the carboxy exchange reaction even at ambient temperature in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO). The acrylate and acrylic acid copolymers are cross-linked using bis[α-(bromomethyl)acrylates] and doped with 10 wt% DABCO, exhibiting processability to obtain a transparent film by hot pressing. The high-speed bond exchange in the network, validated by stress-relaxation tests, allows quick molding with household iron. In addition, the material is applied as an adhesion sheet for plastic and metal substrates. Because dynamic cross-linking with the proposed bond exchange mechanism can be implemented for any polymer bearing carboxyl pendants, our approach can be applied to versatile backbones, which must thus be meaningful in the practical sense. Fast bond exchange reactions is critical for the design of vitrimer and vitrimer-like materials but are not sufficiently explored. Here, the authors use fast bond exchange between α-(acyloxymethyl)acrylate and carboxylic acid resulting in rapid stress relaxation and excellent processability owing to the highly efficient network rearrangement. [ABSTRACT FROM AUTHOR]

Iron-based magnetic nanoparticles (MNPs) have attracted considerable attention as promising draw solutes in forward osmosis processes due to various advantages. In the present study, magnetite (Fe3O4) nanoparticles (MNPs) with diameters in the range of 12 ± 2 nm were synthesized by applying the coprecipitation method and stabilized using (3-aminopropyl)triethoxysilane (APTES). The amino groups of APTES were further functionalized with various amounts of citric acid (CA) and poly(acrylic acid) (PAA) to achieve higher osmotic pressure. The as-prepared and functionalized nanoparticles were characterized using different methods: Fourier-transform infrared spectroscopy (FTIR) confirmed the binding of APTES and CA/PAA on the surface of the MNPs, while the size of the particles was determined by transmission electron microscopy (TEM) and X-ray powder diffraction. The isoelectric point, zeta potential, and the particle size in suspension were determined by dynamic light scattering (DLS)/zeta potential measuring system. The amount of free –COOH groups was determined by conductometric titrations. The amount of organic matter (APTES, CA, and PAA) bound on the surface was determined by thermogravimetric analysis (TG), giving results between 7.6% for samples stabilized with APTES only and 17.5% for samples functionalized with APTES + PAA. TG provides a simple and efficient method for determining the amount of organic compounds bound to the surface of MNPs. The osmotic pressure measurements of double-layer coated MNPs provided encouraging results of up to 28 bar, enabling using the samples as draw solutions in an experimental forward osmosis system. [ABSTRACT FROM AUTHOR]

Drought stress critically hinders agricultural productivity, especially in arid and semi-arid zones. The results of this study show that the application of watermelon rind-based hydrogels (WR hydrogels), synthesized from a watermelon rind, acrylic acid (AA), and acrylamide (AAm), significantly enhanced soil water retention by 77.46% at a 0.3% concentration, increasing the plant height by 28.98% and biomass by 35.28% under controlled greenhouse conditions (25 °C/20 °C day/night temperature cycle, with a 12 h photoperiod at 400–500 μmol·m−2·s−1 of illuminance and 30–40% relative humidity). The accumulation of proline and soluble sugars decreased, indicating reduced osmotic stress in barley subjected to mild and severe drought conditions (6–15% FC and 17–26% FC). The chlorophyll content rose by 16.36%, boosting photosynthetic activity. A correlation and principal component analysis further highlighted the positive effects of hydrogel addition on plant growth and drought resistance. These findings underscore the potential of WR hydrogels as an effective soil amendment for promoting sustainable agriculture in water-limited conditions. [ABSTRACT FROM AUTHOR]

Nine copolymers of acrylic acid and sodium methallyl sulfonate were tested as scale inhibitors in thermal desalination. The nine antiscalants covered molar masses between 2000 and 9500 g.mol–1 and concentrations of sulfonated monomer ranging between 10 and 30 mole percent. A pressure measurement and control (P-MAC) unit and a high-temperature pressurized vessel were used to measure the effectiveness of the scale inhibitors in seawater, concentrated seawater, and model solutions at 125 °C. The effectiveness of the novel copolymers was comparable to commercial antiscalant at times up to 15 min and improved at longer times. Molar mass was a more important determinant of effectiveness than degree of sulfonation, with the greatest mitigation of calcium sulfate precipitation observed for antiscalants of molar mass 2000 to 2500 g.mol–1 regardless of sulfonate content. Antiscalants of molar mass 4500 to 5000 g.mol–1 showed a higher threshold effect than antiscalants of molar mass 7000 to 9500 g.mol–1, with a 30% sulfonated polymer of molar mass 4500 g.mol–1 performing appreciably better than other polymers of a similar molar mass. [ABSTRACT FROM AUTHOR]

Binary and ternary copolymers of acrylonitrile (AN), tert-butyl acrylate (TBA), and n-butyl acrylate (BA) are synthesized through conventional radical polymerization in DMSO in the presence of 2-mercaptoethanol. The thermal behavior of binary and ternary copolymers is studied under argon atmosphere and in air. It is demonstrated that the copolymers of AN contain 1–10 mol.% of TBA split isobutylene upon heating above 160 °C, resulting in the formation of the units of acrylic acid in the chain. The carboxylic groups formed in situ are responsible for the ionic mechanism of cyclization, which starts at lower temperatures compared with pure polyacrylonitrile (PAN) or AN copolymer with BA. The activation energy of cyclization through ionic and radical mechanisms depends on copolymer composition. For the ionic mechanism, the activation energy lies in the range ca. 100–130 kJ/mole, while for the radical mechanism, it lies in the range ca. 150–190 kJ/mole. The increase in the TBA molar part in the copolymer is followed by faster consumption of nitrile groups and the evolution of a ladder structure in both binary and ternary copolymers. Thus, the incorporation of a certain amount of TBA in PAN or its copolymer with BA allows tuning the temperature range of cyclization. This feature seems attractive for applications in the production of melt-spun PAN by choosing the appropriate copolymer composition and heating mode. [ABSTRACT FROM AUTHOR]

Hybrid nanocomposites combining biopolymer fibers incorporated with nanoparticles (NPs) have received increasing attention due to their remarkable characteristics. Inorganic NPs are typically chosen for their properties, such as magnetism and thermal or electrical conductivity, for example. Meanwhile, the biopolymer fiber component is a backbone, and could act as a support structure for the NPs. This shift towards biopolymers over traditional synthetic polymers is motivated by their sustainability, compatibility with biological systems, non-toxic nature, and natural decomposition. This study employed the solution blow spinning (SBS) method to obtain a nanocomposite comprising poly(vinyl pyrrolidone), PVA, and gelatin biodegradable polymer fibers incorporated with magnetic iron oxide nanoparticles coated with poly(acrylic acid), PAA2k, coded as γ-Fe2O3-NPs-PAA2k. The fiber production process entailed a preliminary investigation to determine suitable solvents, polymer concentrations, and spinning parameters. γ-Fe2O3-NPs were synthesized via chemical co-precipitation as maghemite and coated with PAA2k through the precipitation–redispersion protocol in order to prepare γ-Fe2O3-NPs-PAA2k. Biopolymeric fibers containing coated NPs with sub-micrometer diameters were obtained, with NP concentrations ranging from 1.0 to 1.7% wt. The synthesized NPs underwent characterization via dynamic light scattering, zeta potential analysis, and infrared spectroscopy, while the biopolymer fibers were characterized through scanning electron microscopy, infrared spectroscopy, and thermogravimetric analysis. Overall, this study demonstrates the successful implementation of SBS for producing biopolymeric fibers incorporating iron oxide NPs, where the amalgamation of materials demonstrated superior thermal behavior to the plain polymers. The thorough characterization of the NPs and fibers provided valuable insights into their properties, paving the way for their potential applications in various fields such as biomedical engineering, environmental remediation, and functional materials. [ABSTRACT FROM AUTHOR]

Recently, eutectogels have emerged as ideal candidates for flexible wearable strain sensors. However, the development of eutectogels with robust mechanical strength, high stretchability, excellent transparency, and desirable conductivity remains a challenge. Herein, a covalently cross-linked eutectogel was prepared by exploiting the high solubility of oligoethylene glycol in a polymerizable deep eutectic solvent (DES) form of acrylic acid (AA) and choline chloride (ChCl). The resulting eutectogel exhibited high transparency (90%), robust mechanical strength (up to 1.5 MPa), high stretchability (up to 962%), and desirable ionic conductivity (up to 1.22 mS cm−1). The resistive strain sensor fabricated from the eutectogel exhibits desirable linear sensitivity (GF: 1.66), wide response range (1–200%), and reliable stability (over 1000 cycles), enabling accurate monitoring of human motions (fingers, wrists, and footsteps). We believe that our DES-based eutectogel has great potential for applications in wearable strain sensors with high sensitivity and reliability. [ABSTRACT FROM AUTHOR]

A new polymer hyrogel dosimeter based on acrylic acid in polyvinyl alcohol hydrogel matrix was prepared to be used in radiation measurments for radiotherapy treatment. The hydrogel dosimeters were exposed to ionizing radiation using a medical linear accelerator. The hydrogel samples were irradiated at 6 MV beam energy, 600 cGy min−1 dose rate, and various doses up to 50 Gy. UV–VIS Spectrophotometry was used to readout the dose response of non-irradiated and irradiated hydrogel samples at absorbance of 630 nm. The results show the dose response increases strongly with increasing abosrbed doses, with a large linear dose range (2–30 Gy) and dose sensitivity of 0.013 Gy−1 s−1. Moreover, no significant variation in dose response was obseved when the gel samples are irridiated under different dose-rates as well as radiation beam energies. A noticeble change in the stability of the irradiated hydrogel samples was found within the first three days of irradiation, followed by a high post-irradiation stability, for the next 14 days. The non-irridiated samples were stable, up to 10 weeks. [ABSTRACT FROM AUTHOR]

The Expert Panel for Cosmetic Ingredient Safety (Panel) reviewed the safety of 30 vinylpyrrolidone polymers as used in cosmetic products; most of these ingredients have the reported cosmetic function of film former in common. The Panel reviewed data relevant to the safety of these ingredients, and determined that 27 vinylpyrrolidone polymers are safe in cosmetics in the present practices of use and concentration described in the safety assessment. The Panel also concluded that the available data are insufficient to make a determination that 3 vinylpyrrolidone polymers (all urethanes) are safe under the intended conditions of use in cosmetic formulations. [ABSTRACT FROM AUTHOR]

In the present study, grafting of acrylic acid and itaconic acid copolymer onto carboxymethyl cellulose backbone was performed by a free radical polymerization approach to decontamination of crystal violet and malachite green from aqueous media. To promote removal efficiency, various amounts of Cloisite 30B nanoclay were integrated into the hydrogel matrix, and the optimum value based on the removal performance was obtained 6 wt.%. The optimum pH values, initial concentration, and contact time were determined to be 7, 30 mg/L, and 140 min. The kinetic and equilibrium data were well defined by quasi-second-order and Langmuir models. The maximum adsorption capacity of hydrogel and nanocomposite hydrogel from the Langmuir model was obtained at 45.87 and 58.48 mg/g for crystal violet and 25.51 and 36.36 mg/g for malachite green, respectively. The FTIR analysis before and after dye adsorption showed that electrostatic interaction is the main mechanism of the adsorption process. It can be concluded that synthesized adsorbents have high potential in wastewater treatment applications. [ABSTRACT FROM AUTHOR]

Superabsorbent hydrogels demonstrate positive significance as water-retaining materials in agriculture and gardens. The super water-retaining hydrogel (BASA) based on the bamboo powder with the rich sulfonic acid group and carboxyl group was successfully and efficiently synthesized by ultrasonic wave-assisted and polymerization methods. The preparation process has the advantages of mild conditions and process simplification. The impact of reaction conditions (the ionic strength, pH value, cross-linking agent and initiator content) was systematically studied. Characterization methods such as elemental analysis, FTIR, SEM and TGA indicated that the synthesized super water-retaining agent had excellent water retention properties and good stability. The maximal absorbent capacities in ultrapure water and rainwater reached 1047 g g−1 and 952 g g−1, respectively. The water retention properties of BASA were affected by the water quality and ionic strength of water solution. The swelling process is mainly the hydrogen bonding between the active group and the hydrogen atom of the water molecule and the electrostatic interaction of anionic groups such as sulfonic acid groups, but it also includes the synergistic effect of diffusion process. The outcomes demonstrate that BASA is a powerful water absorption hydrogel for soil water retention agent in the agricultural field. [ABSTRACT FROM AUTHOR]

The acrylic acid-grafted functionalized base polyurethane foam (PAA-g-PUf) is synthesized through mutual radiation grafting technique using acrylic acid as functional monomers and polyurethane form (PUf) with macroporous structure as base polymer, for the extraction of lead from the aqoueous waste streams. The incorporation of functionality on PUf is identified and confirmed by FT-IR spectroscopy, degree of grafting and thermal stability by TGA–DSC technique while the surface morphology, and pores dimensions are evaluated by SEM techniques. The kinetics measurements indicate that the synthesized sorbent reaches its saturation sorption capacity within 10 min at ~ 25 °C under near-neutral pH condition. The monolayer sorption capacity of the synthesized PAA-g-PUf for lead ion (Pb2+) is calculated from Langmuir's model and found to be ~ 257 mg g−1, which is quite good as compared to the other functionalized material available. These grafted foams are quite efficient over a wide range of concentrations and temperature of the experimental solutions. In this study, the adsorbed lead ions are eluted out in 0.5 M HCl strippent efficiently. These sorbents exhibit excellent reusability up to five cycles without losing appreciable capacity, suggesting better usability in real water samples for many cycles. The polyurethane foam used was obtained from municipal waste, and hence, they cannot generate any additional secondary waste to the environment and make the process more sustainable and economically viable. [ABSTRACT FROM AUTHOR]

Conductive biohydrogel received prominent application in the diverse field. Hydrogel based on biopolymer is generally biocompatible and degradable but exhibiting poor conductivity. To enhance the conductivity of biohydrogel, composite of bioplomer and synthetic polymer are preferred. This work aims to prepare such composite for the augmentation of conductivity of biohydrogel. Gum Ghatti (GG), a natural biopolymer, was grafted with polyacrylic acid and subsequently cross-linked to form a hydrogel. The synthesized hydrogel was then infused with oxidized multiwalled carbon nanotubes (-o-MWCNTs). The materials underwent comprehensive characterization using techniques, such as FT-IR, XRD, SEM, and TGA-DTA. The grafted GG demonstrated a synergistic blend of biopolymer and polyacrylic acid (AA) properties. The hydrogel's electrical conductivity was systematically investigated at varying loadings of -o-MWCNTs within the GG-cl-P(AA) matrix. As the loading of -o-MWCNTs increased from 10 to 30 mg, there was a notable enhancement in electrical conductivity. However, at higher loading amounts, the electrical conductivity exhibited a subsequent decline. [ABSTRACT FROM AUTHOR]

Actinobacteria cells Rhodococcus erythropolis 4-1 and Rhodococcus erythropolis 11-2 and Proteobacteria Alcaligenes faecalis 2, which have amidase activity, were immobilized by entrapping barium alginate and agarose into the gel structure, as well as by obtaining biofilms on thermally expanded graphite (TEG). The operational stability of such immobilized biocatalysts after storage in frozen and dehydrated form was determined, and a prototype of a conductometric acrylamide biosensor based on such a bioselective agent was developed. The most preferred method for storing immobilized cells was freezing at temperatures from –20 to –80°C; long-term storage is also possible wet at 4–25°C. It was shown that these cells were most preferable for the biodetection of acrylamide A. faecalis 2, immobilized in an agarose gel structure. An agarose gel with bacterial cells immobilized in its structure had greater mechanical strength and stability during successive cycles of conversion of acrylamide into acrylic acid compared to barium alginate gel. The mechanical strength of barium alginate gel can be enhanced by the addition of carbon nanomaterials during cell immobilization. Growing biofilms on carbon materials used for manufacturing electrodes is also promising. Biofilms of R. erythropolis 11-2 on TEG are capable of converting acrylamide into acrylic acid in more than 20 reaction cycles while maintaining at least 50% amidase activity. [ABSTRACT FROM AUTHOR]

In the graphical abstract, we illustrate the innovative design of physical–chemical hybrid crosslinked composite hydrogels that exhibit a unique combination of properties, making them well-suited for advanced applications in flexible electronics and biosensing. These hydrogels demonstrate ideal stretchability and compressibility, alongside excellent adhesion capabilities. Their design is strategically tailored to ensure biocompatibility without compromising the sensitive detection of physiological signals. The graphical representation showcases the multifaceted nature of these materials, highlighting their dynamic responsiveness to mechanical stimuli and their potential to seamlessly interface with biological tissues for real-time monitoring and diagnostic purposes. [Display omitted] With the advancement of wearable and implantable medical devices, hydrogel flexible bioelectronic devices have attracted significant interest due to exhibiting tissue-like mechanical compliance, biocompatibility, and low electrical resistance. In this study, the development and comprehensive performance evaluation of poly(acrylic acid)/ N,N′-bis(acryloyl) cystamine/ 1-butyl-3-ethenylimidazol-1-ium:bromide (PAA/NB/IL) hydrogels designed for flexible sensor applications are introduced. Engineered through a combination of physical and chemical cross-linking strategies, these hydrogels exhibit strong mechanical properties, high biocompatibility, and effective sensing capabilities. At 95 % strain, the compressive modulus of PAA/NB/IL 100 reach up to 3.66 MPa, with the loading–unloading process showing no significant hysteresis loop, indicating strong mechanical stability and elasticity. An increase in the IL content was observed to enlarge the porosity of the hydrogels, thereby influencing their swelling behavior and sensing functionality. Biocompatibility assessments revealed that the hemolysis rate was below 5 %, ensuring their suitability for biomedical applications. Upon implantation in rats, a minimal acute inflammatory response was observed, comparable to that of the biocompatibility control poly(ethylene glycol) diacrylate (PEGDA). These results suggest that PAA/NB/IL hydrogels hold promise as biomaterials for biosensors, offering a balance of mechanical integrity, physiological compatibility, and sensing sensitivity, thereby facilitating advanced healthcare monitoring solutions. [ABSTRACT FROM AUTHOR]