Acrylic Acid Research Articles

Preparation of PANI Modified Hollow Microspheres and Its Application in Anti-static Buffer Foam of OLED Under-display

The polyaniline (PANI) modified hollow microspheres (HMs@PANI) was prepared by in-situ polymerization and then applied as both foaming agent and conductive fillers. The coating of PANI on the surface of hollow microspheres (HMs) was studied, and a dense conductive layer was obtained. Moreover, HMs@PANI was co-doped with acrylic acid and hydrochloric acid in order to improve the dispersion. Finally, the as-obtained HMs@PANI-C=O was added into the polyacrylate matrix, then the multi-functional syntactic foam with both better anti-static property and buffer property was obtained. When the addition of HMs@PANI was 20wt%, the surface resistivity of the foam reached 2.32×106 Ω. Furthermore, the better buffer property, lightweight, compression resistance, and thermal conductive property were also presented, which would be important in the practical application of OLED under-display.

Conductive chitosan/polyaniline hydrogel: A gas sensor for room-temperature electrochemical hydrogen sensing

Hydrogen (H2) has been deemed a source of energy for both stationary and mobile applications to contribute to lowering carbon emissions due to its abundance (which can be extracted from various compounds), environmental friendliness, and high energy density. However, H2 gas is highly flammable and has a fast burning rate. Consequently, the need to ensure human safety and environmental preservation necessitates the development of hydrogen sensors that exhibit heightened sensitivity, a reduced detection threshold, and quick response times. Herein, we present the synthesis of a ternary hydrogel composite, chitosan-crosslinked poly(acrylic acid)-based polyaniline hydrogel (Cs-cl-pAA/PANI), which was developed to function as a cathode material in hydrogen sensing applications. The structural and optical properties of ternary cathode materials were evaluated using various analytical techniques, and hydrogen sensing was studied using electrochemical techniques. The electrochemical sensing characteristics of the hydrogel matrix were improved by including polyaniline (PANI) as a result of the overlapping of localised π-electrons in the p-orbitals. The sensitivity of the Cs-cl-pAA/PANI hydrogel was determined to be 48.7845 μA M, with a reaction time of 0.6s, recovery time of 2s, and detection limit of 3.682 μM. The sensor also exhibited outstanding restoration and repeatability.

Fabrication and evaluation of stable amorphous polymer-drug composite particles via a nozzle-free ultrasonic nebulizer

We present a promising method for producing amorphous drug particles using a nozzle-free ultrasonic nebulizer with polymers, specifically polyvinylpyrrolidone (PVP), poly(acrylic acid) (PAA), and Eudragit® S 100 (EUD). Model crystalline phase drugs–Empagliflozin, Furosemide, and Ilaprazole–are selected. This technique efficiently produces spherical polymer-drug composite particles and demonstrates enhanced stability against humidity and thermal conditions, compared to the drug-only amorphous particles. The composite particles exhibit improved water dissolution compared to the original crystalline drugs, indicating potential bioavailability enhancements. While there are challenges, including the need for continuous water supply for ultrasonic component cooling, dependency on the solubility of polymers and drugs in volatile organic solvents, and mildly elevated temperatures for solvent evaporation, our method offers significant advantages over traditional approaches. It provides a straightforward, flexible process adaptable to various drug-polymer combinations and consistently yields spherical amorphous solid dispersion (ASD) particles with a narrow size distribution. These attributes make our method a valuable advancement in pharmaceutical drug formulation and delivery.

Design and preparation of reticular superabsorbent hydrogel material with nutrient slow-release and high shear strength for ecological remediation of abandoned mines with steep slopes

In order to solve ecological remediation issues for abandoned mines with steep slopes, a kind of hydrogels with high cohesion and water-retaining were designed by inorganic mineral skeleton combining with polymeric organic network cavities. This eco-friendly hydrogel (MFA/HA-g-p(AA-co-AM)) was prepared with acrylic acid (AA)-acrylamide (AM) as network, which was grafted with humic acids (HA) as network binding point reinforcement skeleton and polar functional group donors, KOH-modified fly ash (MFA) as internal supporter. The maximum water absorption capacities were 1960 g/g for distilled water, which followed the pseudo-second-order model. This super water absorption was attributed to the first stage of 62 % fast absorption due to the high specific surface area, pore volume and low osmotic pressure, moreover, the multiple hydrophilic functional groups and network structure swell contributed to 36 % of the second stage slow adsorption. In addition, the pore filling of water in mesoporous channels contributed the additional 2 % water retention on the third stage. The high saline-alkali resistance correlated with the electrostatic attraction with MFA and multiple interactions with oxygen-containing functional groups in organic components. MFA and HA also enhanced the shear strength and fertility retention properties. After 5 cycles of natural dehydration and reabsorption process, these excellent characteristics of reusability and water absorption capacity kept above 97 %. The application of 0.6 wt% MFA/HA-g-p(AA-co-AM) at 15° slope could improve the growth of ryegrass by approximately 45 %. This study provides an efficient and economic superabsorbent material for ecological restoration of abandoned mines with steep slopes.

Innovative wearable solutions: Semi-releasing ion-conductive lignin hydrogel sensors for enhanced practicability

The severe negative effects of impurities adhering to the external surface of wearable devices can significantly influence the signal transmission, performance, and lifespan of hydrogel sensors. Herein, we developed an ion-conducting hydrogel sensor with a strong adhesive side and a non-adhesive side, similar to a “semi-releasing material.” This hydrogel, formulated using deep eutectic solvents obtained from choline chloride and acrylic acid, contained lignin. This versatile material, exhibiting properties similar to semi-releasing materials, was treated with an AlCl3 solution on one side. Additionally, the hydrogel was successfully used as a highly adhesive strain sensor for real-time monitoring of various human activity signals. Moreover, the hydrogel demonstrated excellent environmental tolerance and conductivity. Lignin extracted from wood flour endowed the hydrogel sensor with excellent adhesion energy (up to 427.1 J/m2) and UV resistance. Treatment of hydrogels with AlCl3 completely eliminated their adhesiveness, thereby enhancing fracture elongation and tensile strength. This improvement can be attributed to the absence of carboxyl groups and the formation of a metal-phenolic network. The implementation of this convenient and efficient strategy provides a more feasible approach to address challenges related to impurity adhesion and signal transmission in flexible wearable devices.

Rapid self-healing nanocomposite gel crosslinked by LDH for lost circulation control

Lost circulation presents a complex challenge in drilling operations. Ascribed to the favorable remaining in fracture, strong resistance to efflux, and entire gel block rather than individual particles, the self-healing gels have been broadly applied as lost circulation material (LCM). In this study, we utilized layered bimetallic hydroxide (LDH) as a dynamic crosslinking agent to synthesize a novel nanocomposite (NC) gel through in-situ polymerization following the stripping of LDH in acrylic acid (AA) solution. LDH/PAA NC gels exhibit excellent self-healing properties, rheological strength, mechanical properties and adhesion properties, with these attributes being influenced by the LDH content. At 110 °C, the optimal LDH/PAA NC gel rapidly self-healed in bentonite mud within 1h, revealing storage modulus (G′) of 4041Pa, tensile strength of 8.04 kPa, and adhesion strength of 2.1 kPa. Visual plugging tests revealed that the LDH/PAA NC gel could withstand pressures up to 4MPa, surpassing the capabilities of MA gel, which lacked self-healing properties. These findings highlight the potential of LDH/PAA NC gels as efficient LCM, offering a promising solution for controlling lost circulation during drilling operations.

Fabrication of polypropylene-g-poly(acrylic acid) based microfibers by combination of photo-induced metal-free ATRP and electrospinning process

Fabrication of polypropylene-g-poly(acrylic acid) based microfibers by combination of photo-induced metal-free ATRP and electrospinning process

Dehydration of lactic acid to prepare acrylic acid over Hβ zeolite modified by acid treatment and Rb ion-exchange

Dehydration of lactic acid to prepare acrylic acid over Hβ zeolite modified by acid treatment and Rb ion-exchange

Fluorination effects on non-covalent binding forces: A rotational study on the 2-(trifluoromethyl)acrylic acid–water complex

This study explores the effects of the −CF3 group on non-covalent interactions through a comprehensive rotational investigation of the 2-(trifluoromethyl)acrylic acid–water complex. Employing Fourier transform microwave spectroscopy complemented by quantum chemical calculations, two isomers, i.e., s-cis and s-trans structures, have been observed in the pulsed jet. Based on relative intensity measurements, the s-cis to the s-trans population ratio was experimentally estimated to be ∼ 1:1.2. Subsequently, a comparison of the non-covalent interactions was carried out between the three similar complexes, acrylic acid–water, methacrylic acid–water, and 2-(trifluoromethyl)acrylic acid–water, offering quantitative insights into fluorination affecting the strength of the formed hydrogen bonds important, e.g., in molecular recognition.

Versatile multi-lithiophilic metal oxide nano seeds embedded in hollow carbon nanospheres via electrostatically functional template for dendrite-free lithium metal anodes

Lithium metal anodes, which are promising candidates for anode materials in Li-ion batteries, are highly regarded for their combination of high energy density and low electrochemical potential, making them a compelling option for next-generation anodes. However, the growth of dendritic Li during the charging and discharging processes, along with the resulting decrease in stability and efficiency, poses a significant obstacle to the commercialization of Li metal anodes. To address the challenges associated with Li metal anodes, we propose the use of hollow carbon incorporating zinc oxide (ZnO) and magnesium oxide (MgO) as anode materials. ZnO has high lithiophilicity, enabling selective reactions with Li ions, and MgO exhibits a low nucleation overpotential. By placing these two substances inside the hollow carbon structure, stable Li growth can occur within the hollow carbon, enabling the formation of a reliable Li metal anode. Furthermore, to simplify and precisely synthesize the proposed structure, polystyrene-b-polyacrylic acid was introduced. Metals such as Zn and Mg can be uniformly attached to the hollow carbon through the carboxylic group of acrylic acid. The synthesized structure exhibited significantly improved Li storage performance compared to that of hollow carbon. It demonstrated superior metrics, achieving a Coulombic efficiency of 99.8% over 350 cycles. The introduction of Zn and Mg with distinct properties effectively enhanced the internal storage performance of Li in hollow carbon.

Novel Phenothiazine and Coumarin based Sensitizers: Design, Synthesis and Photoelectrochemical Application by Anchoring on CdS Nanowires

Novel metal-free organic dyes (E)-2-cyano-3-(10-(prop-2-yn-1-yl)-10H-phenothiazin-3-yl)acrylic acid (PPC) and (E)-2-cyano-3-(10-((1-((7-methyl-2-oxo-2H-chromen-4-yl)methyl)-1H-1,2,3-triazol-4-yl)methyl)-4a,10a-dihydro-10H-phenothiazin-3-yl)acrylic acid (PCTC) was synthesized and then anchored to 1D cadmium sulfide nanowires (1D CdS NWs) for application in photoelectrochemical dye-sensitized solar cell (DSSC). The 1D CdS nanowires were interconnected into a nanonetwork using solution chemistry in a straightforward and efficient manner. The UV-visible spectroscopy, cyclic voltammetry and density functional theory (DFT) were effectively employed to analyze the characteristics of PPC and PCTC. The sensitizer-anchored CdS nanowires have a broader range of light absorption in the UV-visible spectrum compared to bare CdS nanowires. The complete device has the assembly FTO, compact CdS, CdS nanowires, synthesized dye and counter electrode. In photovoltaic assessment, the PCTC and PPC devices yield 3.19 and 3.04 times, respectively, more efficiency than naked CdS nanowires under conventional sunshine illumination (100 mW/cm2, AM 1.5G). The obtained results provide strong evidence supporting the presence of rising external quantum efficiency (EQE) and show a high level of consistency with the optical tests.

Simultaneous Rosiglitazone Release and Low-Density Lipoprotein Removal by Chondroitin Sodium Sulfate/Cyclodextrin/Poly(acrylic acid) Composite Adsorbents for Atherosclerosis Therapy.

Atherosclerosis (AS) is characterized by the accumulation of substantial low-density lipoprotein (LDL) and inflammatory response. Hemoperfusion is commonly employed for the selective removal of LDL from the body. However, conventional hemoperfusion merely focuses on LDL removal and does not address the symptom of plaque associated with AS. Based on the LDL binding properties of acrylated chondroitin sodium sulfate (CSA), acrylated beta-cyclodextrin (CD) and acrylic acid (AA), along with the anti-inflammatory property of rosiglitazone (R), the fabricated AA-CSA-CD-R microspheres could simultaneously release R and facilitate LDL removal for hemoperfusion. The AA and CSA offer electrostatic adsorption sites for LDL, while the CD provides hydrophobic adsorption sites for LDL and weak binding sites for R. According to the Sips model, the maximum static LDL adsorption capacity of AA-CSA-CD-R is determined to be 614.73 mg/g. In dynamic simulated perfusion experiments, AA-CSA-CD-R exhibits an initial cycle LDL adsorption capacity of 150.97 mg/g. The study suggests that the weakened inflammatory response favors plaque stabilization. The anti-inflammatory property of the microspheres is verified through an inflammation model, wherein the microsphere extracts are cocultured with mouse macrophages. Both qualitative analysis of iNOS\TNF-α and quantitative analysis of IL-6\TNF-α collectively demonstrate the remarkable anti-inflammatory effect of the microspheres. Therefore, the current study presents a novel blood purification treatment of eliminating pathogenic factors and introducing therapeutic factors to stabilize AS plaque.

Preparation and properties of acrylate/polyvinyl alcohol self-healing hydrogels based on hydrogen bonds and coordination bonds

Abstract Despite the widespread attention garnered by self-healing hydrogels in various fields, achieving a balance between high mechanical strength and self-healing capability remains a challenge. Particularly, the addition of fillers in the fabrication of spray-coated waterproof materials hinders the movement of molecular chains. Simultaneously, the self-repair of metal ions is hindered by issues such as a prolonged required time and low repair rate. Therefore, we introduce a polyvinyl alcohol (PVA) solution subjected to freeze–thaw cycles into the acrylic acid magnesium/calcium hydrogel system, creating a self-healing hydrogel with an interpenetrating polymer network (IPN). Due to the abundance of hydroxyl groups on the PVA molecular chains, during the freezing process, some PVA chains form microcrystals that do not dissolve upon thawing at room temperature. These microcrystals act as cross-linking points, connecting PVA chains into a 3D network. Consequently, the hydrogel, under the dual effects of hydrogen bonds and coordination bonds, exhibits excellent mechanical properties and the ability to self-heal at room temperature. Furthermore, by adjusting the concentration of the PVA solution, the mechanical properties and healing ability of the hydrogel can be tailored to meet various construction requirements.

Synthesis, Surface Modification and Magnetic Properties Analysis of Heat-Generating Cobalt-Substituted Magnetite Nanoparticles.

Here, we present the results of the synthesis, surface modification, and properties analysis of magnetite-based nanoparticles, specifically Co0.047Fe2.953O4 (S1) and Co0.086Fe2.914O4 (S2). These nanoparticles were synthesized using the co-precipitation method at 80 °C for 2 h. They exhibit a single-phase nature and crystallize in a spinel-type structure (space group Fd3¯m). Transmission electron microscopy analysis reveals that the particles are quasi-spherical in shape and approximately 11 nm in size. An observed increase in saturation magnetization, coercivity, remanence, and blocking temperature in S2 compared to S1 can be attributed to an increase in magnetocrystalline anisotropy due to the incorporation of Co ions in the crystal lattice of the parent compound (Fe3O4). The heating efficiency of the samples was determined by fitting the Box-Lucas equation to the acquired temperature curves. The calculated Specific Loss Power (SLP) values were 46 W/g and 23 W/g (under HAC = 200 Oe and f = 252 kHz) for S1 and S2, respectively. Additionally, sample S1 was coated with citric acid (Co0.047Fe2.953O4@CA) and poly(acrylic acid) (Co0.047Fe2.953O4@PAA) to obtain stable colloids for further tests for magnetic hyperthermia applications in cancer therapy. Fits of the Box-Lucas equation provided SLP values of 21 W/g and 34 W/g for CA- and PAA-coated samples, respectively. On the other hand, X-ray photoelectron spectroscopy analysis points to the catalytically active centers Fe2+/Fe3+ and Co2+/Co3+ on the particle surface, suggesting possible applications of the samples as heterogeneous self-heating catalysts in advanced oxidation processes under an AC magnetic field.

Synthesis and characterization of styrene‐maleic acid block copolymers with acrylic and methacrylic acids for potential use in membrane protein extraction

AbstractStyrene‐maleic acid (SMA) block copolymers with acrylic acid (AA) and methacrylic acid (MAA) were synthesized via a 3‐step process comprising: (1) photopolymerization of styrene and maleic anhydride in solution to yield an alternating styrene‐maleic anhydride (SMAnh) copolymer, (2) copolymerization of SMAnh with AA and MAA to yield SMAnh‐b‐AA and SMAnh‐b‐MAA block copolymers, and (3) base‐catalyzed hydrolysis of the anhydride groups to yield water‐soluble SMA‐b‐AA and SMA‐b‐MAA block copolymers. Copolymer compositions and average molecular weights were determined by the synthesis methodology used in which reversible chain transfer was a key component. Copolymer characterization was carried out by a combination of techniques, namely: ATR‐FTIR, 1H‐NMR, dilute‐solution viscometry, GPC, DSC, and TGA. These novel SMA block copolymers have been designed with a view to their use in membrane protein (MP) extraction from plant extracts and other naturally occurring substances of potential therapeutic value. The main function of the AA or MAA blocks is to widen the operational pH range of SMA in terms of (a) maintaining its water solubility at low pH and (b) stabilizing its MP assemblies in solution.

Preparation and ammonium adsorption behavior of interpenetrating polymer networks hydrogel of chitosan‐g‐poly(acrylic acid)/bentonite and chitosan‐glutaraldehyde

AbstractIn this article, new interpenetrating polymer network (IPN) hydrogel as an efficient adsorbent for ammonium was prepared by a two‐step process. First, semi‐IPN hydrogel of chitosan‐g‐poly(acrylic acid)/bentonite (CAB) and chitosan (CTS) was synthesized by grafting polymerization in the presence of exfoliated bentonite as both cross‐linking agent and nanoscale inorganic filler. Second, cross‐linking polymer network of chitosan‐glutaraldehyde (CGA) was formed by reaction of CTS with glutaraldehyde (GA). The obtained IPN hydrogel (CAB/CGA) was characterized by Fourier‐transform infrared spectroscopy, scanning electron microscopy and its swelling degree and PZC value were also measured. These results demonstrate that copolymerized graft reaction was occurred between CTS, AA and bentonite forming CAB, and CGA presented as a cross‐linker in CAB/CGA polymer network. CAB/CGA has a moderate swelling degree of 7.8. CAB/CGA exhibits high adsorption capacity and fast adsorption rate for ammonium. Adsorption process reaches equilibrium in 30 min and fits well to Langmuir adsorption model with a fairly high maximum adsorption capacity of 41.06 mg g−1. The material has a good regeneration ability. After five times of adsorption–desorption, there was almost no decrease in ammonium adsorption capacity. Moreover, the low swelling degree leads to an improvement in material strength and a reduction of equipment cost.

PH-responsive and mechanical strong chitosan-based hydrogel reinforced with rice straw cellulose micro-fibrils for efficient removal of cu(II)

Straw and chitosan are underutilized raw materials, which could make a significant contribution to sustainable development. Herein, a novel chitosan-based hydrogel incorporating rice straw cellulose micro-fibrils (SCMF) was prepared to effectively remove Cu(II). FTIR and SEM showed that straw cellulose-g-poly (acrylic acid)/chitosan-g-poly (acrylic acid) interpenetrating polymer networks were prepared and the hydrogel SCCH had a 3D porous structure after cross-linking with AA. The swelling properties of SCCH were studied and compared in various pH solution. The results indicated that SCCH replayed pH responsibility, which had the largest and smallest swelling capacity at pH9.18 and pH4.00 respectively. The pseudo-second-order kinetic model can be effectively used to evaluate swelling kinetics of hydrogels. The effects of contact time and initial concentration on Cu(II) ion removal were investigated. The equilibrium adsorption capacity (Qe) was 209.2 mg/g and the obtained results indicated that the adsorption kinetics conformed to the pseudo-second-order. Chemical adsorption combined with porous physical adsorption endowed SCCH excellent swelling and adsorption properties. Tensile, compression, bending and twisting test convinced that SCMF played a significant role on the improvement of mechanical strength. This novel 3D porous chitosan-based hydrogel was identified to be a promising sorbent with advantages of excellent sorption and mechanical properties.

Sustained release delivery of favipiravir through statistically optimized, chemically cross-linked, pH-sensitive, swellable hydrogel.

In the current work, favipiravir (an antiviral drug) loaded pH-responsive polymeric hydrogels were developed by the free redical polymerization technique. Box-Behnken design method via Design Expert version 11 was employed to furnish the composition of all hydrogel formulations. Here, polyethylene glycol (PEG) has been utilized as a polymer, acrylic acid (AA) as a monomer, and potassium persulfate (KPS) and methylene-bisacrylamide (MBA) as initiator and cross-linker, respectively. All networks were evaluated for in-vitro drug release (%), sol-gel fraction (%), swelling studies (%), porosity (%), percentage entrapment efficiency, and chemical compatibilities. According to findings, the swelling was pH sensitive and was shown to be greatest at a pH of 6.8 (2500%). The optimum gel fraction offered was 97.8%. A sufficient porosity allows the hydrogel to load a substantial amount of favipiravir despite its hydrophobic behavior. Hydrogels exhibited maximum entrapment efficiency of favipiravir upto 98%. The in-vitro release studies of drug-formulated hydrogel revealed that the drug release from hydrogel was between 85 to 110% within 24 h. Drug-release kinetic results showed that the Korsmeyer Peppas model was followed by most of the developed formulations based on the R2 value. In conclusion, the hydrogel-based technology proved to be an excellent option for creating the sustained-release dosage form of the antiviral drug favipiravir.

A low cost, acrylic acid based low swelling hydrogel

Low swelling hydrogels have attracted much attention because of good mechanical stability, whereas they suffer the shortcoming of high cost. Here, we demonstrate a low-cost low swelling hydrogel which produced using acrylic acid as the main precursor. This hydrogel has a switchable hydrophobic or hydrophilic surface depending on the copolymerized monomers and adjuvants. The gel is moldable and flexible. In fresh water, swelling ratio of the gel is around 0.2 g/g. In saline solutions, it has adjustable swelling ratio while maintaining low swelling properties. This gel has the characteristics of a low BET surface area of 3.9758 m2/g and an average pore diameter of 20 nm. The gel could be used as a smart adaptive material and shape-stable adsorption material in saline environments.

CQDs-Cross-Linked Conductive Collagen/PAA-Based Nanocomposite Organohydrogel Coupling Flexibility with Multifunctionality for Dual-Modal Sensing of Human Motions.

Conductive hydrogels are ideal materials for intelligent medical devices, human-machine interfaces, and flexible bioelectrodes due to their adjustable mechanical properties and electrical responsiveness, whereas it is still a great challenge to achieve the integration of excellent flexibility and biocompatibility into one hydrogel sensor while also incorporating self-healing, self-adhesion, environmental tolerance, and antimicrobial properties. Here, a nanocomposite conductive organohydrogel was constructed by using collagen (Col), alginate-derived carbon quantum dots (OSA-CQDs), poly(acrylic acid) (PAA), ethylene glycol reduced AgNPs, and Fe3+ ions. Depending on OSA-CQDs with multiple chemical binding sites and high specific surface area as cross-linkers, while coupling highly biologically active Col chains and PAA chains are serving as an energy dissipation module, the resulting organohydrogel exhibited excellent flexibility (795% of strain, 193 kPa of strength), high cell compatibility (>95% survival rate), self-healing efficiency (HE = 79.5%), antifreezing (-20 °C), moisturizing (>120 h), repeatable adhesion (strength >20 kPa, times >10), inhibitory activity against Escherichia coli and Staphylococcus aureus (9 and 21.5 cm2), conductivity, and strain sensitivity (σ = 1.34 S/m, gauge factor (GF) = 11.63). Based on the all-in-one integration of multifunction, the organohydrogel can collaboratively adapt to the multimode of strain sensing and electrophysiological sensing to realize wireless real-time monitoring of human activities and physiological health. Therefore, this work provides a new and common platform for the design and sensing of next-generation hydrogel-based smart wearable sensors.