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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]

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]

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]

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]

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]

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]

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]

[Display omitted] There are few explorations that have integrated multiple properties into photonic microobjects in a facile and controlled manner. In this work, we present a straightforward method to integrate different functions into individual photonic microobject. Droplet-based microfluidics was used to produce uniform droplets of an aqueous dispersion of monodispersed SiO 2 nanoparticles (NPs). The droplets evolved into opal-structured photonic microballs upon complete evaporation of water. After infiltration of an aqueous solution of acrylamide (AAm) and acrylic acid (AAc) monomers into the interstices among SiO 2 NPs, opal-structured SiO 2 NPs/pAAm- co -AAc hydrogel composite photonic microballs were obtained upon UV irradiation. Afterwards, a wet etching process was introduced to etch the microballs in a controlled manner, yielding individual photonic microball composed of an SiO 2 NPs/pAAm- co -AAc composite opal core and a neat pAAm- co -AAc shell. The pendant carboxylic acid groups in the skeleton of the hydrogel matrix were further utilized to react with positively charged compounds, such as Ruthenium compound containing fluorescent polymers. The resulting photonic microobjects eventually featured with localized stimulus-responsive properties and multiple colors under different modes. The multifunctional photonic microobjects were discovered to have fivefold of anticounterfeiting properties when used as building blocks for anticounterfeiting structures and may have other potential applications. [ABSTRACT FROM AUTHOR]

Balancing biocompatibility and drug-loading efficiency in nanoparticles presents a significant challenge. In this study, we describe the facile fabrication of poly (acrylic acid)-mesoporous zinc phosphate/polydopamine (PAA-mZnP/PDA) Janus nanoparticles (JNPs). The PDA half-shell itself can serve as a photothermal agent for photothermal therapy (PTT), as well as to offers sites for polyethylene glycol (PEG) to enhance biocompatibility. Concurrently, the mesoporous ZnP core allows high loading of doxorubicin (DOX) for chemotherapy and the Cy5.5 dye for fluorescence imaging. The resultant PAA-mZnP/PDA-PEG JNPs exhibit exceptional biocompatibility, efficient drug loading (0.5 mg DOX/1 mg JNPs), and dual pH/NIR-responsive drug release properties. We demonstrate the JNPs' satisfactory anti-cancer efficacy, highlighting the synergistic effects of chemotherapy and PTT. Furthermore, the potential for synergistic fluorescence imaging-guided chemo-phototherapy in cancer treatment is illustrated. Thus, this work exemplifies the development of biosafe, multifunctional JNPs for advanced applications in cancer theranostics. Facile fabrication of monodispersed nanomedicine with multi-cancer killing modalities organically integrated is nontrivial and becomes more challenging under the biocompatibility requirement that is necessary for the practical applications of nanomedicines. In this study, we creatively designed PAA-mZnP/PDA JNPs and fabricated them under mild conditions. Our method reliably yields uniform JNPs with excellent monodispersity. To maximize functionalities, we achieve fourfold advantages including efficient drug/fluorescent dye loading, PTT, pH/NIR dual-responsive properties, and optimal biocompatibility. The as-fabricated JNPs exhibit satisfactory anti-cancer performance both in vitro and in vivo , and demonstrate the potential of JNPs in fluorescence imaging-guided synergistic cancer chemo-phototherapy. Overall, our research establishes a pathway in versatile inorganic/polymer JNPs for enhanced cancer diagnosis and therapy. [Display omitted] [ABSTRACT FROM AUTHOR]

Due to their capacity of water absorption, super absorbent polymers (SAPs) are greatly requested in hygienic applications, thus representing large volume products needing for a good biodegradability. This study aims to develop new SAPs for baby diapers by combining sodium alginate (SA) and cellulose nanocrystals (CNC) with acrylic acid (AA). The effect of different AA/SA ratios and CNC concentrations in the presence of ammonium persulfate (APS) as an initiator, and N–N-methylene bis-acrylamide (NMBA) as a cross-linker is investigated. We assess morphological and physicochemical properties of the SAPs, as well as their absorption characteristics and rheological properties. The results show that SAPs with AA/SA weight ratio of 70:30 containing 2% w/w CNC have the highest water absorption capacity, i.e., 78.4 g/g in saline solution. These SAPs also demonstrate high retention capacity and better absorption capacity under load than other SAPs. We further optimize the formulation by increasing the neutralization degree of AA and reducing the solid content, reaching an absorption capacity in the salt solution up to 100.08 g/g. Finally, the absorbent core made with fewer amounts of SAPs and fluff pulp led to functional properties superior to those of commercial baby diapers. High polysaccharide content SAPs could contribute to improve diaper sustainability. [ABSTRACT FROM AUTHOR]

Ionogels are considered as ideal candidates for constructing flexible electronics due to their superior electrical conductivity, flexibility, high thermal and electrochemical stability. However, it remains a great challenge to simultaneously achieve high sensitivity, repeated adhesion, good self‐healing, and biocompatibility through a straightforward strategy. Herein, inspired by nucleobase‐tackified strategy, a multifunctional adhesive ionogel is developed through one‐step radical polymerization of acrylated adenine/uracil (Aa/Ua) and acrylic acid (AA) monomers in sodium caseinate (SC) stabilized liquid metal dispersions. As a soft conductive filler, the incorporating of liquid metal not only improves the electrical conductivity, but also enhances the mechanical strength, satisfying the stretchable sensing application. The large amount of noncovalent interactions (hydrogen bonding, metal coordination, and ion‐dipole interactions) within the networks enable the ionogels to possess excellent stretchability, skin‐like softness, good self‐healing, and strong adhesion. Based on these desirable characteristics, the ionogel is suitable for wearable strain sensors to precisely detect diverse human movements under extreme environments. Moreover, the seamless adhesion with human skin allows the ionogel to function as bioelectrode patch for long‐term and high‐quality electrophysiological signal acquisition. This research provides a promising strategy for designing ionogels with tailored functionalities for wearable electronics that satisfy diverse application requirements. [ABSTRACT FROM AUTHOR]

Programmable materials are desirable for a variety of functional applications that range from biomedical devices, actuators and soft robots to adaptive surfaces and deployable structures. However, current smart materials are often designed to respond to single stimuli (like temperature, humidity, or light). Here, a novel multi‐stimuli‐responsive composite is fabricated using direct ink writing (DIW) to enable programmability in both space and time and computation of logic operations. The composite hydrogels consist of double‐network matrices of poly(N‐isopropylacrylamide) (PNIPAM) or poly(acrylic acid) (PAA) and sodium alginate (SA) and are reinforced by a high content of cellulose nanocrystals (CNC) (14 wt%) and nanofibers (CNF) (1 wt%). These composites exhibit a simultaneously tunable response to external stimuli, such as temperature, pH, and ion concentration, enabling precise control over their swelling and shrinking behavior, shape, and mechanical properties over time. Bilayer hydrogel actuators are designed to display bidirectional bending in response to various stimuli scenarios. Finally, to leverage the multi‐responsiveness and programmability of this new composite, Boolean algebra concepts are used to design and execute NOT, YES, OR, and AND logic gates, paving the way for self‐actuating materials with embodied logic. [ABSTRACT FROM AUTHOR]

Energy losses and purity of product gases in alkaline water electrolysis strongly depend on properties of a separator positioned between the electrodes. This paper reports on heterogeneous separators based on microporous polysulfone membranes modified by graft co-polymerization of acrylic acid. After neutralization with KOH, the pores of the modified membranes were filled with potassium polyacrylate, a superabsorbent material forming hydrogel upon intake of an aqueous electrolyte. Under electrolysis conditions of 50 °C and atmospheric pressure, increasing amount of hydrogel in pores suppresses hydrogen permeability without apparent reduction of ionic conductivity. We have identified the product of ionic resistance and hydrogen flux as a suitable parameter to compare performance of separators of various thickness. In terms of this parameter, present separators surpass the performance of Zirfon™ Perl UTP 500 tested under the identical conditions. Ex-situ aging test in 30 wt% KOH at 60 °C has revealed preservation of high wettability for up to 1340 h. [Display omitted] • Graft co-polymerization of acrylic acid is achieved on microporous polysulfone membranes. • Modified membranes exhibit high ionic conductivity and low hydrogen permeability under electrolysis conditions at 50 °C. • High wettability is retained in KOH electrolyte at 60 °C for 1340 h. [ABSTRACT FROM AUTHOR]

Drawing inspiration from recent advances in microwave ablation (MWA) induced in situ tumor vaccination, a colloidal hydrogel comprising amphoteric gelatin nanoparticles and poly (acrylic acid) (PAA)‐calcium carbonate nanorods (PAA‐CaCO3 NRs) is developed to deliver the microwave‐sensitive agent sodium fluoride (NaF) which can also act as a glycolysis inhibitor in conjunction with the blockade of the T‐cell Ig and ITIM domain (TIGIT), a coinhibitory receptor expressed by both natural killer (NK) cells and T cells. The combination of NaF with microwave (MW) thermal‐dynamic sensitization effectively reversed the acidic and immunosuppressive tumor microenvironment (TME). Moreover, the incorporation of anti‐TIGIT monoclonal antibody (aTIGIT) molecules amplified both the innate and adaptive immune responses by counteracting the exhaustion of NK and effective CD8+ T cells. This augmentation resulted in enhanced tumor elimination and suppression of tumor metastasis and recurrence. Thus, this study underscores the potential of colloidal hydrogel‐sensitized MWA therapy, in conjunction with aTIGIT treatments, as a promising clinical strategy for in situ cancer vaccination. [ABSTRACT FROM AUTHOR]

The objective of this study was to explore the applicability of biocompatible quince seed mucilage hydrogel as a promising material for drug delivery systems. In this investigation, the hydrogel was synthesized through the graft copolymerization of acrylic acid and allyl polyvinyl alcohol onto quince seed mucilage in an aqueous solution under an argon atmosphere. Characterization of the synthesized hydrogel was performed using Fourier‐transform infrared spectroscopy (FTIR), field emission scanning electron microscope (FE‐SEM), and thermogravimetric analysis (TGA). Subsequently, the developed hydrogel served as a carrier for ceftriaxone antibiotic release in both distilled water and a buffer solution with a pH of 7.4. The results demonstrated an impressive encapsulation efficiency of 96.1% for ceftriaxone within the hydrogel matrix. Additionally, the adsorption properties of ceftriaxone onto the proposed hydrogel structures (I, II, and III) were theoretically investigated in the aqueous phase using Monte Carlo adsorption locator calculations in Materials Studio2017. Our findings revealed strong adsorption on structure (III) compared to structures (I and II), with respective theoretical energies of −2.836 kcal/mol, −2.840 kcal/mol, and −2.127 kcal/mol. Therefore, the proposed hydrogel structure (III) emerges as a promising candidate for drug delivery applications, emphasizing its potential as an efficient carrier system. [ABSTRACT FROM AUTHOR]

The aim of this work is a synthesis of suitable hydrogel to produce slow‐release fertilizer using recycled cellulose which is obtained from waste paper. For this purpose, initially, we extracted alpha cellulose from waste paper and modified it to obtain carboxymethyl cellulose (CMC). Then, the CMC was converted to a suitable hydrogel through in situ graft copolymerization of acrylic acid and vinyl acetate in the presence of methylene bisacrylamide as a crosslinker. The various factors that affect hydrogel synthesis, such as the amounts of CMC, monomers, initiator, and crosslinker, were evaluated. In the optimized formulation, the weight ratio of monomers to CMC is 7, the molar ratio of monomers to each other is 1, and the crosslinker is used as 3 molar percent of monomers. The products were characterized using Fourier transform infrared, thermal gravimetric analysis, and scanning electron microscope analyses. The swelling behavior of the synthesized hydrogels was evaluated in different environments, such as distilled water, tap water, salt water, and different pH levels. The swelling ratio increases with an increase in pH level. Between the synthesized hydrogels, the best one was selected for slow‐release fertilizer production and loaded with 20‐20‐20 fertilizer (NPK), and the release behavior was evaluated. In an alkaline pH, there was a long time for NPK release within a slow‐release medium and even after 361 h, the release process was continued. Also, the performance of the fertilizer‐loaded hydrogel in soil using water holding capacity and water retention ratio tests were evaluated. [ABSTRACT FROM AUTHOR]

Herein, a novel hydrogel (HG-cl-poly(AA)) was synthesized by grafting acrylic acid (AA) onto Hing gum (HG) using methylene-bis-acrylamide (MBA) as a cross-linker and ammonium persulfate (APS) as an initiator in a hot air oven. The percentage swelling of the hydrogel was examined by optimizing various reaction parameters to ensure its maximum swelling percentage. The formation of crosslinked networks was confirmed using Fourier-Transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and thermogravimetric analysis (TGA) techniques. The surface area and hydrophilicity of the prepared hydrogel were determined using Brunauer–Emmett–Teller analyzer and wettability studies, demonstrating a clear correlation with adsorption. The adsorption of crystal violet (CV) dye on the prepared hydrogel was studied via a batch adsorption system based on the amount of adsorbent, immersion time, pH level, and initial dye concentration. The prepared hydrogel showed a 99% removal rate and an excellent adsorption capacity of 492.61mg/g due to the electrostatic, H-bonding, and dipole–dipole interactions between the adsorbent surface and dye molecules. The results were further analyzed using the Langmuir, Freundlich, and Tempkin isotherm models. The study suggests consistency with the pseudo-second-order kinetic model (R2=0.998), further supported by the best data fit with the Langmuir isotherm model (R2=0.991). The thermodynamic study results indicated that the adsorption process is endothermic and spontaneous. Regeneration (desorption) studies showed that the prepared hydrogel could remove CV dye from an aqueous solution and maintain the highest adsorption capacity even after multiple adsorption and desorption cycles. Therefore, the prepared HG-cl-poly(AA) hydrogel could be a potential adsorbent for dye removal and have an admirable capacity for cleaning the aquatic environment. [ABSTRACT FROM AUTHOR]

A new galvanic cell design of a self‐powered and 3D‐printable soft sensor showing health monitoring, object recognition, and contactless hand gesture recognition, is reported. The soft sensor consists of a 3D‐printed poly(acrylic acid) (PAA) hydrogel electrolyte layer, a soft anode layer, and a soft cathode layer. The anode layer is a 3D‐printed and Cu2+ cross‐linked poly(N,N‐dimethylacrylamide‐co‐3‐alanine‐2‐hydroxypropylmethacrylate) (PDA) hydrogel dispersed with Cu metal particles (PDA/Cu2+/Cu hydrogel), while the cathode layer is a bottom thin layer of the PAA hydrogel containing MnO2 (PAA/MnO2). Using graphite films as the soft electrodes, the soft sensor is finally assembled. The soft sensor has high force and temperature sensitivities. It gives different electric current responses under stretching, bending, pressing, and impact loading. The soft sensor is demonstrated to be useful in detecting human motion and physiological activities, e.g., breath. Based on the force and contactless temperature sensitivities, the soft sensor is used to recognize human hand gestures and plastic balls with different diameters. This 3D printable soft sensor with self‐powering, contactless motion capturing, and multi‐pimulus sensing capabilities illustrates a new pathway to make soft sensory devices for healthcare and human‐machine interaction applications. [ABSTRACT FROM AUTHOR]

Aqueous rechargeable zinc‐ion batteries are emerging as green and safe energy devices owing to their high energy density and eco‐friendliness. The bottleneck is the inhomogeneous nucleation resulting in the growth of Zn dendrites and the parasitic side reactions at the anode. Herein, an electrochemical anode engineering strategy is demonstrated to curb the uncontrolled dendritic growth and side reactions. It involves the in situ generation of a solid‐electrolyte interface based on a Zn nanoparticle‐embedded poly(acrylic acid) hybrid layer (PAA‐nZn) on the anode. The homogeneously distributed polar functionalities and porous nature of the polymer regulate the uniform zinc ion flux, and the embedded zinc particle serves as nucleation sites for zinc plating. The hybrid layer reduces the nucleation overpotential and promotes instantaneous nucleation. The symmetrical cell made with PAA‐nZn@Zn has a lifecycle of >860 h with a voltage gap of 28 mV. The full cell fabricated by pairing the engineered anode with α‐MnO2 cathode showed a high discharge specific capacity of 238.3 mAh g−1 at 0.2 A g−1 with a capacity retention of 81.76% after 200 cycles and a long lifecycle. The electrochemical engineering of the anode suppresses the dendritic growth and protects the anode from unwanted side reactions and passivation. [ABSTRACT FROM AUTHOR]

This study investigates the cradle-to-gate life cycle assessment of four acrylic acid production routes. Acrylic acid, an important industrial chemical, is currently produced using fossil fuel-based propylene but it can be sustainably produced from biodiesel derived glycerol through different pathways that involve intermediates such as acrolein, allyl alcohol, or lactic acid. Environmental impacts, including global warming potential, water footprint, acidification, eutrophication, ozone layer depletion, photochemical smog, and human toxicity, are evaluated. Glycerol-based processes exhibit significant environmental impacts mainly due to the energy-intensive production of epichlorohydrin-derived glycerol. The total potential global warming for glycerol-based processes having intermediates allyl alcohol, lactic acid and acrolein, was 1.67 × 105, 1.80 × 105 and 1.34 × 105 kg CO2 eq. FU-1 respectively, with epichlorohydrinderived glycerol, whilst this value was 0.552 × 105 kg CO2 eq. FU-1 for the propylene-based process. However, changing the source of glycerol to purified crude glycerol from the biodiesel industry results in a considerable reduction of the environmental impact. A sensitivity analysis using the two-factor interaction (2FI) model showed that the global warming potential varies from 0.676 × 105 to 1.45 × 105 kg CO2 eq. FU-1 depending on the purification method used to purify crude glycerol and the glycerol content in the crude glycerol. It showed that a vacuum distillation purification process with 50% glycerol content had the least global warming values. This assessment provides insights into environmental performance trade-offs, guiding efforts towards more sustainable acrylic acid production and emphasizing the potential of using by-products from other industries to enhance the sustainability in chemical production processes. [ABSTRACT FROM AUTHOR]

Hydrogel‐based wearable sensors eventually experience dehydration, which negatively impacts their function, leading to decreased sensitivity. Monitoring the real‐time water retention rate and sensing performance of wearable flexible sensors without dismantling them remains a significant difficulty. In this study, a molecule having aggregation‐induced emission (AIE) properties in an aqueous environment has been developed and produced, which can combine with anionic guar gum and acrylic acid to create an AIE hydrogel. Wearable sensing electronic devices have the capability to track motion signals at various joints of the human body. Additionally, they can effectively and visually monitor dehydration status during extended periods of operation. The fluorescence intensity of the hydrogel is primarily influenced by the level of aggregation of luminous monomers inside the network. This level of aggregation is predominantly governed by the hydrogel's water retention rate. Hence, the extended duration of hydrogel dehydration can be manifested through alterations in their fluorescence characteristics, which are employed for strain sensing. This approach enables users to assess the water retention of hydrogels with greater efficiency, eliminating the requirement for disassembling them from the completed electrical gadget. In summary, the use of AIE‐based fluorescent hydrogels will advance the progress of intelligent wearable electronics. [ABSTRACT FROM AUTHOR]

Microgel particles can play a key role, e.g., in drug delivery systems, tissue engineering, advanced (bio)sensors or (bio)catalysis. Amine-functionalized microgels are particularly interesting in many applications since they can provide pH responsiveness, chemical functionalities for, e.g., bioconjugation, unique binding characteristics for pollutants and interactions with cell surfaces. Since the incorporation of amine functionalities in controlled amounts with predefined architectures is still a challenge, here, we present a novel method for the synthesis of responsive core–shell nanogels (dh < 100 nm) with a poly(N-isopropylacrylamide) (pNIPAm) core and a polyamine shell. To achieve this goal, a surface-functionalized pNIPAm nanogel was first prepared in a semi-batch precipitation polymerization reaction. Surface functionalization was achieved by adding acrylic acid to the reaction mixture in the final stage of the precipitation polymerization. Under these conditions, the carboxyl functionalities were confined to the outer shell of the nanogel particles, preserving the core's temperature-responsive behavior and providing reactive functionalities on the nanogel surface. The polyamine shell was prepared by the chemical coupling of polyethyleneimine to the nanogel's carboxyl functionalities using a water-soluble carbodiimide (EDC) to facilitate the coupling reaction. The efficiency of the coupling was assessed by varying the EDC concentration and reaction temperature. The molecular weight of PEI was also varied in a wide range (Mw = 0.6 to 750 kDa), and we found that it had a profound effect on how many polyamine repeat units could be immobilized in the nanogel shell. The swelling and the electrophoretic mobility of the prepared core–shell nanogels were also studied as a function of pH and temperature, demonstrating the successful formation of the polyamine shell on the nanogel core and its effect on the nanogel characteristics. This study provides a general framework for the controlled synthesis of core–shell nanogels with tunable surface properties, which can be applied in many potential applications. [ABSTRACT FROM AUTHOR]

This study provides a detailed picture of how a protein (lysozyme) complexes with a poly(acrylic acid) polyelectrolyte (PAA) in water at the atomic level using a combination of all-atom molecular dynamics simulations and experiments. The effect of PAA and temperature on the protein's structure is explored. The simulations reveal that a lysozyme's structure is relatively stable except from local conformational changes induced by the presence of PAA and temperature increase. The effect of a specific thermal treatment on the complexation process is investigated, revealing both structural and energetic changes. Certain types of secondary structures (i.e., α-helix) are found to undergo a partially irreversible shift upon thermal treatment, which aligns qualitatively with experimental observations. This uncovers the origins of thermally induced aggregation of lysozyme with PAA and points to new PAA/lysozyme bonds that are formed and potentially enhance the stability in the complexes. As the temperature changes, distinct amino acids are found to exhibit the closest proximity to PAA, resulting into different PAA/lysozyme interactions; consequently, a different complexation pathway is followed. Energy calculations reveal the dominant role of electrostatic interactions. This detailed information can be useful for designing new biopolymer/protein materials and understanding protein function under immobilization of polyelectrolytes and upon mild denaturation processes. [ABSTRACT FROM AUTHOR]

[Display omitted] Hydrogel microneedle patches have emerged as promising platforms for painless, minimally invasive, safe, and portable transdermal drug administration. However, the conventional mold-based fabrication processes and inherent single-functionality of such microneedles present significant hurdles to broader implementation. Herein, we have developed a novel approach utilizing a precursor solution of robust nanocomposite hydrogels to formulate photo-printable inks suitable for the direct 3D printing of high-precision, triple-responsive hydrogel microneedle patches through digital light processing (DLP) technology. The ink formulation comprises four functionally diverse monomers including 2-(dimethylamino)ethyl methacrylate, N -isopropylacrylamide, acrylic acid, and acrylamide, which were crosslinked by aluminum hydroxide nanoparticles (AH NPs) acting as both reinforcing agents and crosslinking centers. This results in the formation of a nanocomposite hydrogel characterized by exceptional mechanical strength, an essential attribute for the 3D printing of hydrogel microneeedle patches. Furthermore, this innovative 3D printing strategy facilitates facile customization of microneedle geometry and patch dimensions. As a proof-of-concept, we employed the fabricated hydrogel microneedles for transdermal delivery of bovine serum albumin (BSA). Importantly, these hydrogel microneedles displayed no cytotoxic effects and exhibited triple sensitivity to pH, temperature and glucose levels, thereby enabling more precise on-demand drug delivery. This study provides a universal method for the rapid fabrication of hydrogel microneedles with smart responsiveness for transdermal drug delivery applications. [ABSTRACT FROM AUTHOR]

Poly(eutectic) elastomers, as an emerging category of flexible electronic materials, have garnered growing interest for their cost-effectiveness, non-volatility, and biocompatibility. Nonetheless, they encounter challenges including limited functionalities, sensitivity, durability, and mechanical properties. This study involved synthesizing various MXene-doped poly(eutectic) elastomers using robust acrylamide and soft acrylic acid as organic monomers, minor MXene nanosheets as inorganic fillers and physical crosslinkers, and a rapid in-situ photopolymerization method within 2 min. Owing to the synergistic effect of thermodynamic self-assembly, high-density hydrogen bonding, and cation-dipole interactions in the matrix networks, the resulting non-covalently crosslinked elastomers exhibited remarkable mechanical strength (up to ∼ 16.2 MPa) and impressive tensile properties (nearly 700 %), along with rapid electrical self-healing (within 0.046 s) and the ability to withstand loads up to 2500 times their weight following self-healing without fracturing. Notably, these elastomers also demonstrated excellent microstrain (1 %–10 %) sensitivity with a gauge factor of 2.02, wide temperature tolerance (−20 °C ∼ 60 °C), outstanding harsh temperature durability (−20 °C) exceeding 22,000 cycles, and antibacterial properties. Furthermore, these elastomers-assembled strain sensors displayed real-time and rapid response in human motion detection and wireless signal transmission, presenting a promising approach for designing functionally integrated elastomeric materials. [Display omitted] • A novel MXene-doped poly(eutectic) conductive elastomers are facilely fabricated. • Tunable mechanical properties by adjusting ratios of soft monomer, hard monomer and physical crosslinker. • Dynamic non-covalent interactions confer rapid electrical self-healing (<46 m s). • Over 22,000 cycles durability in harsh temperatures (−20 °C). • Real-time response to strain, human motion and wireless signal transmission. [ABSTRACT FROM AUTHOR]

Poly(acrylic acid) (PAAc) hydrogels are essential functional materials. However, their mechanical properties do not meet the required standards. In this study, a one‐pot method is employed to prepare cellulose‐reinforced PAAc hydrogels by dissolving allyl cellulose (AC) in acrylic acid (AAc) solutions. Fourier transform infrared (FTIR), solid‐state 13C nuclear magnetic resonance (NMR), and thermogravimetric (TG) analysis are used to demonstrate that the incorporation of AC results in the formation of covalent and hydrogen bonds, which contribute to the crosslink network of the PAAc hydrogels. Significantly, by modifying the ratio of AC to AAc in the pre‐polymerization solution, the prepared AC–PAAc hydrogels exhibit a transition from transparent to opaque. This suggests that phase separation is induced by hydrogen bonding. The occurrence of phase separation is verified by observing the hydrogel microstructures using scanning electron microscopy. Phase separation leads to enhanced polymer–polymer interactions in the hydrogels, resulting in a maximum fracture stress of 2.34 MPa. The AC–PAAc hydrogels display distinct swelling behavior under various pH conditions. Moreover, they demonstrate differences in transparency and mechanical properties when exposed to dimethyl sulfoxide (DMSO) and water, indicating their responsiveness to solvents. This work demonstrates the great potential of enhancing the mechanical performance and responsiveness of PAAc hydrogels. [ABSTRACT FROM AUTHOR]

Organic substances in which the-OH group is directly attached to the carbon atom are called alcohols. Unsaturated alcohols are obtained by replacing the hydrogen of ethylene or acetylene-type compounds with a hydroxyl group. Allyl alcohol, the first representative of the class of unsaturated alcohols, contains oxygen. Allyl alcohol is used in optical resins, protective glasses, paints and coatings and polymer cross-linking agents, as well as in the production of pharmaceuticals, organic chemicals, plastics, herbicides, and pesticides. In organic chemistry, alcohols can be oxidized to aldehydes, ketones, carboxylic acids, and esters that carry a higher oxidation state of carbon. Therefore, the selective oxidation of alcohols is an important issue. The properties and selective oxidation reaction of allyl alcohol were investigated in the presented work. [ABSTRACT FROM AUTHOR]

Superabsorbent polymer gels are widely used in commercial areas, such as in hygiene products. A key aspect in these and other applications is the gel swelling kinetics, and a key factor of influence on that is the hydrophobicity of the gel. This paper reports on the synthesis of superabsorbent polymer microgel particles with four differently hydrophobic crosslinkers: N,N'‐methylenebisacrylamide (MBAA), N,N'‐ethylenebisacrylamide (EBAA), N,N'‐propylenebisacrylamide (PBAA), and N,N'‐butylenebisacrylamide (BBAA). This work uses droplet‐based microfluidics to produce uniform and well‐defined microgel specimen and study the influence of the crosslinker hydrophobicity on the swelling kinetics. In particular, this work determines swelling constants and their dependencies on the temperature of the swelling medium as well as the activation energies of swelling in relation to the crosslinker hydrophobicity. This work finds two competing effects, leading to a narrow window in which the activation energy of the swelling of the microgels decreases with increasing crosslinker hydrophobicity. [ABSTRACT FROM AUTHOR]