Colloid and Polymer Science最新文献

In this work, we consider the preparation of magnetic magnetite nanoparticles (MNPs, Fe₃O₄)) by chemical precipitation method, modified with biocompatible polymers such as polyethyleneimine (PEI) and chitosan (CS) to get Fe₃O₄@PEI and Fe₃O₄@CS, respectively, alongside electrospun polyamide (PA) nanofibers and their sorption properties towards some of the synthetic food azo dyes (Tartrazine (TRT), Sunset Yellow FCF (SY), Azorubine (AR), and Ponceau 4R (P-4R)). Spherical MNPs (7.5 ± 0.2 nm, TEM) and PA electrospun nanofibers (52 ± 3 nm to 104 ± 11 nm, SEM) were prepared, with a specific surface area of 101 m² g⁻¹ (MNPs) and 44 m² g⁻¹ (PA). The pore space volume of PA nanofibers was 0.024 cm³ g⁻¹ which is much less than for MNPs (Fe₃O₄, 0.282 cm³ g⁻¹; Fe₃O₄@CS, 0.218 cm³ g⁻¹; and Fe₃O₄@PEI, 0.154 cm³ g⁻¹). The saturation magnetization of Fe₃O₄@CS (40 emu g⁻¹) and Fe₃O₄@PEI (43 emu g⁻¹) was slightly lower than that of Fe₃O₄ (48 emu g⁻¹). Sorption studies under optimized conditions (pH, time, sorbent mass) achieved 95–99% dye recovery. The kinetics of dye sorption was studied, and pseudo-second-order of sorption was preferable. For Fe₃O₄@PEI, the maximum sorption capacity (q_max, mg g⁻¹) values increased to 150 (SY), 151 (AR), 176 (TRT), and 204 (P-4R); for Fe₃O₄@CS, 57 (SY), 104 (TRT), 139 (P-4R), and 142 (AR); and for PA, 28 (Ar), 31 (TRT), 33 (P-4R), and 39 (SY) within the Langmuir model. The difference in sorption capacity and recovery may be attributed to steric factors and the chemical structure of the azo dye molecule.

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The excellent electrical properties of polypropylene (PP) make it a widely used material for power cable insulation. However, its vulnerability to the potential impact of water molecules and aggressive ions in complex environments should be taken into consideration. The microscopic interaction mechanism between H₂O, Cl⁻, NO₃⁻, and SO₄²⁻ and polypropylene power cable is investigated in this study using a combination of density functional theory and molecular dynamics methods. The analysis of between molecules and hybrid systems of PP provides insights into the influence mechanism of active sites, interaction energy, and cohesive energy density on the reaction. The results reveal that the H-U site of PP exhibits a higher propensity for interaction with water molecules and aggressive ions in the intermolecular, with the largest interaction energy observed between SO₄²⁻ and PP. In the hybrid system, not only does SO₄²⁻ exhibit the highest interaction energy, but it also displays superior cohesive energy density and exerts stronger erosion on PP materials. This study elucidates the microscopic interaction mechanism between water molecules and aggressive ions with polypropylene power cable in complex operating environments from the microscopic level, providing a specific theoretical foundation for modifying the erosion resistance of PP materials.

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With the development of flexible electronics and smart devices, the performance of high-dielectric polyurethane materials is more demanding, and an in-depth understanding of the relationship between their structure and dielectric properties is crucial for material design. In this work, a series of polyurethane materials with different hard segment content were synthesized, using poly(tetramethylene ether)glycol (PTMG) and poly(carbonate diol) (PCDL) as the soft segments, and 4,4′-diphenylmethane diisocyanate (MDI) and 1,4-butanediol (BDO) as the hard segments. The effects of hard segment content on the microphase separation, mechanical properties, and dielectric properties of the polyurethane were systematically investigated. The results revealed that with increasing hard segment content, the degree of microphase separation, tensile strength, and dielectric constant of the polyurethane all increased. Among them, the sample with a hard segment content of 55% (PU-55%) exhibited the best overall performance and exhibited the most pronounced microphase separation, with a dielectric constant of 10.50 at 10² Hz and a tensile strength of 18.33 MPa. In addition, it was found that N,N-dimethylformamide (DMF) produces dipole–dipole interactions with precursor molecules (MDI, PTMG, and PCDL) during the synthesis process, thereby modulating the polarity of the reaction environment. This work provides meaningful guidance for structure modulation and performance optimization of polyurethane materials.

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The applications of ultrasonic energy have a broad interest in enhancing polymer properties, effectively enabling mini-emulsion formation of free radicals inside the polymer backbone. This method offers a rapid, energy-efficient approach, producing high-quality resulting polymer compared to conventional techniques. In this study, a novel cellulose-based biopolymer functionalized with 18-Crown-6 was synthesized via ultrasonic-assisted mini-emulsion free radical polymerization for the efficient removal of toxic lead (Pb²⁺) and cadmium (Cd²⁺) ions from aqueous solutions. The synthesized (CMC–co–18-Crown-6) biopolymer was thoroughly characterized using FTIR, UV–Vis, and SEM techniques to confirm structural integrity and successful functionalization, with an average pore diameter of 0.9 ± 0.2 µm and an average fiber diameter of 1.2 ± 0.3 µm. Batch adsorption experiments were conducted to investigate the influence of pH, contact time, and initial ion concentration on metal uptake. The maximum adsorption efficiency was observed at pH 5, with equilibrium reached at 120 min. Kinetic studies revealed that the adsorption process followed a pseudo-second-order model, indicating chemisorption as the dominant mechanism. The polymer demonstrated higher affinity toward Pb²⁺ than Cd²⁺, attributed to the ionic size compatibility with the crown ether cavity. Regeneration studies showed over 90% adsorption efficiency retained after four cycles, indicating excellent reusability. These findings suggest that the 18-Crown-6-functionalized cellulose biopolymer is a promising, cost-effective, and environmentally friendly material for the targeted removal of hazardous heavy metals from contaminated water systems.

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Boron-containing compounds represent promising drug candidates not only as antibacterial agents but also for the treatment of a wide range of diseases. However, due to their low water solubility, drug delivery systems are required to enhance their bioavailability. Cryogel membranes, synthesized at low temperatures, are among the biocompatible carrier systems that offer elastic properties, making them suitable for efficient drug delivery applications. This study aims to characterize quercetin-boronate-loaded poly(2-hydroxyethyl methacrylate) (pHEMA)-based cryogel membranes, evaluate their antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) and multidrug-resistant Escherichia coli (MDR E. coli), and investigate the molecular docking interactions of this compound with the target bacterial proteins. Following the synthesis of quercetin-boronate-loaded cryogel membranes (QBM), their structural and morphological properties were characterized using Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The prepared membranes were found to be biocompatible against L929 fibroblast cells. At the 8th hour, QBM2 cryogel membranes exhibited an inhibition rate of 90.4% against MRSA and 98% against MDR E. coli. These findings were further supported by SEM images, which demonstrated the absence of bacterial colonies on QBM-loaded membranes, while bacterial presence was evident on the surfaces of unloaded membranes. Molecular docking analysis revealed that quercetin-boronate exhibited the highest binding affinity towards the 5NC5 protein (− 6.174 kcal/mol) and the lowest towards the 1MWT protein (− 2.619 kcal/mol).

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Biopolymer-based hydrogels with high mechanical strength have gained great popularity for biomaterials where safety and reliability are highly required. However, most existing biopolymer-based hydrogels are prepared through complicated procedures, usually involving elaborate chemical modification, sophisticated composite technology to combine with reinforcements, and fancy methods to achieve biocompatibility. Here, a facile and effective strategy is demonstrated to fabricate mechanically strong physical hydrogels based on biopolymers without any synthesized polymers or additional reinforcements. The obtained hydrogels are mechanically strong owing to the presence of ionic bonds and coordination bonds as physical crosslinkings. The hydrogel displays regulable mechanical performance within a wide spectrum under various strain rates, and a sandwiched structure with a porous inside architecture. This facile and effective strategy provides a new perspective for the mechanically strong physical hydrogel network construction, which can be further extended to other polymer combinations for physical hydrogels and even chemical hydrogels.

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This research focuses on formulating a microemulsion (ME)-based lyotropic liquid crystal (LC) system to enhance the topical delivery of apremilast for psoriasis treatment. Using Captex 300 as the oil phase and a 3:1 ratio of TPGS to Tween 80 as surfactants, pseudo-ternary phase diagrams were constructed to identify ME regions capable of transitioning into LC phases upon water addition. The optimized system formed a structurally stable LC matrix beyond 20% water content. Structural characterization by FTIR and DSC confirmed drug-excipient compatibility and the absence of degradation. Cryo-SEM imaging revealed interconnected aqueous channels indicative of mesophase development, while polarized microscopy confirmed the formation of birefringent LC phases. The in vitro drug release from the LC matrix was significantly sustained, with less than 40% release over 72 h, in contrast to the rapid release (> 90%) from the pure drug suspension. Time-lapse studies on agar confirmed gradual lateral expansion and prolonged structural integrity of the LC matrix. Drug release kinetics best fit the Higuchi and Korsmeyer–Peppas models, indicating diffusion-driven release. In vivo studies in mice demonstrated enhanced skin retention: 11.77 ± 1.42 µg/cm² in the stratum corneum and 8.50 ± 0.94 µg/cm² in viable layers at 12 h—far superior to plain gel counterparts. Histological analysis showed no signs of irritation or structural damage following application, confirming excellent skin compatibility. The LC system provided a stable, biocompatible platform for controlled apremilast release and deep skin retention, positioning it as a promising topical alternative to oral administration for psoriasis management.

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Slick-water fracturing fluids have become widely employed in reservoir stimulation due to their low viscosity and minimal residue content. As a vital component of hydraulic fracturing systems, drag reducers play a pivotal role in reducing operational friction resistance and enhancing hydrocarbon recovery efficiency. At present, conventional powder and emulsion-based drag reducers often suffer from drawbacks such as poor solubility, slow dissolution rates, insufficient stability, and environmental concerns. In this study, a water-in-water drag reducer PFR was successfully synthesized via aqueous dispersion polymerization using acrylamide (AM) and methacryloxyethyltrimethyl ammonium chloride (DMC) as monomers, with 2, 2′-azobis[2-(2-imidazolin-2-yl) propane] dihydrochloride (VA-044) as the initiator in an ammonium sulfate solution containing PDH as the dispersion stabilizer. A systematic investigation was conducted to evaluate the effects of key polymerization parameters, including the molecular weight of dispersion stabilizer PDH, ammonium sulfate concentration, initiator dosage, and monomer solid content/ratio, on the aqueous dispersion polymerization process. Through comprehensive optimization studies, the optimal synthesis formulation and processing conditions for PFR were successfully established. The resulting PFR exhibited a high molecular weight of up to 8.75 × 10⁶ g/mol, near-complete solubility within 10 min, temperature resistance up to 90 °C, a swelling inhibition rate of 78.18%, and a drag reduction rate of 78.25%. These characteristics highlight PFR’s exceptional stability, fluidity, and shear resistance and temperature resistance, positioning it as a promising candidate for enhanced oil recovery applications.

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A water-in-water drag reducer PFR for slick-water fracturing fluid was synthesized by the aqueous dispersion polymerization. It can withstand a temperature of 90 °C, dissolve almost completely within 10 min, has an anti-expansion rate of 78.18%, and a drag reduction rate of 78.25%.

Novel composites of covalent triazine polymer/melamine–formaldehyde microsphere (CTP/MF-x) were successfully synthesized via a simple one-pot solvothermal method. The resulted materials were characterized using FTIR, XRD, SEM, BET, zeta potential, and TGA analyses. SEM images showed that the MF microspheres were well-dispersed within the CTP matrix, forming CTP-coated core–shell structures that contained 60 wt% MF microspheres (CTP/MF-60). BET analysis indicated that the CTP composite containing 30 wt% MF microspheres (CTP/MF-30) exhibits enhanced surface area and pore volume (12.2 m² g⁻¹ and 0.056 cm³ g⁻¹, respectively) compared to MF microspheres alone and possesses an intermediate pore size (11.6 nm) relative to the individual components. The CTP/MF-30 composite was used as an adsorbent to study the adsorption of model methylene blue (MB) and Congo red (CR) dyes. At pH 7.0 and 3.5, adsorbent dosages of 5 and 10 mg, along with contact times of 10 and 25 min, achieved a removal efficiency of approximately 92% for CTP/MF-30 in MB and CR solutions (10 mg L⁻¹), resulting in maximum adsorption capacities of 136.9 and 86.2 mg g⁻¹, respectively. The enhanced adsorption efficiency of the composites, compared to their individual components, indicates a synergistic effect. Adsorption processes were further examined through isotherm and kinetic studies, which demonstrated a better fit with the Langmuir and the pseudo-second-order model, respectively. Moreover, CTP/MF-30 showed selectivity for the MB cationic dye in MB-CR mixed solution at neutral pH, which made it an attractive candidate for separating oppositely charged dyes.

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( +)-Pinoresinol (PIN), a bioactive lignan with antifungal, anti-inflammatory, and chemo-preventive properties, faces pharmaceutical challenges due to poor aqueous solubility, instability, and irritancy. To address these limitations, we engineered sodium alginate (SA)/sodium lignosulfonate (LS) composite gel beads (SA/LS@PIN) as a multifunctional drug carrier. The beads were fabricated through Ca²⁺-mediated cross-linking, where LS integration enhanced structural stability and drug-loading capacity by modulating the gel matrix architecture. Systematic characterization revealed that LS incorporation (1–3% w/v) optimized bead morphology and improved drug entrapment efficiency (0.85% vs. 0.53% for SA-only beads). Under simulated gastrointestinal conditions, SA/LS@PIN exhibited pH-triggered release kinetics: LS delayed PIN release in gastric fluid while promoting intestinal-specific delivery via Ca²⁺-dissociation mechanisms. The composite demonstrated dual functionality, combining controlled release with antioxidant activity (26.64% DPPH radical scavenging attributed to LS-derived sulfonate and hydroxyl groups) and high biocompatibility (> 80% cell viability at 3% LS). This sustainable platform integrates pH-responsive drug delivery, oxidative stress mitigation, and low cytotoxicity, offering a promising strategy for biomedical and nutraceutical applications.