Colloid and Polymer Science最新文献

A safe and low-toxic γ-CD-MOFs was firstly synthesized by an improved hydrothermal method in this study, and then the drug-loaded γ-CD-MOFs (Cur@CD-MOFs) were prepared through in situ adsorption, using curcumin (Cur) as drug model. Finally, polyethylene glycol-functionalized chitosan (CS-g-mPEG) was used to modify Cur@CD-MOFs to form cyclodextrin supramolecular composites (Cur@CD-MOFs/CS-g-mPEG). The structure and morphology were characterized by FT-IR, XRD, TGA, N₂ adsorption, and SEM. In addition, the stability, in vitro drug release, antioxidant, antibacterial, and biocompatibility properties were investigated. The results showed that curcumin was loaded into γ-CD-MOFs with drug loading capacity of 43.86 ± 1.63% and encapsulation efficiency of 29.48 ± 3.56%, and the release rate after 120 h was 33.2%, under the conditions of pH = 1.2 and 37 °C. Besides, CS-g-mPEG modified Cur@CD-MOFs were successfully prepared, which had excellent mesoporous properties, thermal stability, and bioavailability. After modification, the DPPH free radical scavenging rate after 30 min was 59.4%, compared with pure Cur of 49.1%; the inhibition rate against Escherichia coli and Staphylococcus aureus was 98%, and the cell proliferation rate after 48 h was 98.7%, showing enhanced antioxidant, antibacterial, and biocompatibility properties. These cyclodextrin supramolecular composite materials can be widely applied as low-toxicity, edible and effective drug delivery system in the food and pharmaceutical industries.

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A safe and non-toxic functionalized cyclodextrin-based metal organic framework as an effective drug delivery system was constructed in this study. This MOF has good stability and biocompatibility and can achieve long-acting release. It can be used as a delivery system to incorporate drugs into food additives or packaging films for application in the food field, which can also deliver drugs for a long time for the treatment of some diseases.

This study demonstrates the successful valorization of sago by-products—sago pulp and trunk—as renewable resources for a functional edible coating. Microcrystalline cellulose (MCC) was derived from the sago pulp, and activated carbon was produced from the sago trunk. An I-optimal design was employed to optimize the coating formulation, using the concentrations of MCC and activated carbon as the primary variables. The performance of the coating was evaluated based on two key responses: its antimicrobial activity against Escherichia coli and Bacillus subtilis, and its ability to reduce the weight loss of coated strawberries over time. The model predicted an optimal formulation at 0.9 wt% MCC and 1.56 wt% activated carbon. During validation, the model accurately predicted the coating’s barrier properties against weight loss. However, the experimentally observed antimicrobial inhibition zones for both bacterial strains significantly surpassed the model’s predictions. This discrepancy suggests a potent synergistic effect between the components. Despite the model’s underestimation of the biological activity, this research confirms that sago by-products can be transformed into effective, value-added edible packaging with promising antimicrobial and preservation capabilities.

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Graphene oxide was functionalized by dopamine to synthesize polydopamine-reduced graphene oxide (PDRGO). PDRGO was further applied as a template and reductant to reduce silver ion to form silver nanoparticles (PDRGO-Ag). Then, the PDRGO-Ag was incorporated into waterborne polyurethane (WPU) by in situ emulsification to fabricate the PDRGO-Ag embedded WPU nanocomposite films (WPU/PDRGO-Ag). Herein, the PDRGO-Ag was regarded as a photothermal agent that offers effective and controllable photothermal converters for bactericidal applications. Meanwhile, silver nanoparticles acted as an antibacterial agent that endow synergistically enhanced antibacterial properties to the PDRGO-Ag. The resulting film exhibited exceptional antibacterial performance against both E. coli and S. aureus. Moreover, the WPU/PDRGO-Ag films showed improved mechanical properties. The development of this light-induced functional WPU-based film opens a new pathway to antibacterial composite coatings.

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Bacitracin-loaded PVA/PMMA nanofibers were fabricated via electrospinning and optimized through a Quality by Design (QbD) approach using Box–Behnken Design (BBD) to optimize critical process parameters flow rate (0.1–0.3 mL/h), voltage (7.9–10.1 kV), and spinneret–collector distance (12–16 cm). The optimized conditions (0.2 mL/h, 9 kV, 14 cm) yielded uniform nanofibers (~201 nm) with high entrapment efficiency (94%). Comprehensive physicochemical characterization (DSC, FT-IR, XRD, TGA, SEM) confirmed amorphous drug dispersion, polymeric compatibility, thermal stability, and smooth, bead-free morphology. In vitro release studies demonstrated a biphasic profile, 38% burst in the first hour followed by sustained release culminating in ~90% cumulative release over 72 h driven by non-Fickian diffusion. In vivo evaluation in a Sprague–Dawley rat excisional wound model revealed 99% wound closure by day 14, significantly outperforming placebo and control groups. Histological analysis corroborated accelerated epithelialization and collagen deposition without adverse tissue reactions. These findings establish that bacitracin-loaded PVA/PMMA nanofibers deliver prolonged antimicrobial activity and promote superior wound healing, positioning them as promising candidates for advanced topical wound dressings.

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To obtain the green waterproof takeaway food packaging material, in this study, konjac glucomannan (KGM) was used as a strong skeleton material for preparing aerogels by freeze-drying method, and KGM/starch nanoparticles (SNPs) aerogels were prepared by adding potato starch. The mechanical properties, thermal conductivity, and water wettability of KGM/SNPs aerogels with different mass fractions in polydimethylsiloxane (PDMS) were studied. The composite aerogel has a three-dimensional network structure due to chemical bonding, showing the desired hydrophobicity, stability, mechanical properties, and self-cleaning feature. The effective combination among KGM, SNPs, and PDMS was confirmed, and the starch belonged to V-type crystalline starch. The surface roughness of the whole composite can increase with increasing the KGM/SNPs aerogel content, and the enhanced surface bubble structure can improve the surface roughness and water contact angle (WCA). When the KGM/SNPs aerogel content is 10%, the average surface roughness can reach 5.51 nm with 117.1° of WCA, showing a hydrophobicity. The whole composite shows a strong surface self-cleaning performance. The thermal conductivity of the composite can decrease with increasing the KGM/SNPs content, attributed to more complex air heat transfer pathways, the enhanced closed cell structure in aerogel, the increased specific surface area, and more complex pore structure. This study opens up a new direction for fabricating the green sustainable take-away food packaging materials with favorable mechanical properties and hydrophobicity.

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This study addresses cold-flow deformation, sluggish shear-thickening, and poor energy dissipation in shear-thickening gels (STGs) via solvent-assisted integration of optimally dispersed carbon nanotubes (CNTs, 0 ~ 1.0 weight percent wt.%). Borate-crosslinked STG matrices were synthesized using hydroxyl-terminated polydimethylsiloxane and boric acid. Rheology showed 0.25 wt.% CNT maximized storage modulus enhancement: 124.5 kPa at 0.1 Hz (463% increase over pure STG) and 284.2 kPa at 100 Hz, while maintaining viscoelastic balance. Similarly, compressive modulus (100 mm/min) increased from 93 kPa (pure STG) to 259 kPa. Tensile stress at 100 mm/min reached 82.7 kPa (21.8 times higher). Impact absorption significantly improved: peak force reduced by 80.1% and dissipation duration prolonged by 206.5% versus non-buffered impacts. Helmet simulations confirmed 27.7% peak force reduction and 26.2% longer impact duration. Optimal CNT dispersion facilitated synergistic energy dissipation mechanisms, thus enabling the design of protective STGs with enhanced impact performance.

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Currently, the glass transition temperature (T_g) of traditional damping polyurethane elastomers (PUEs) remains far below room temperature. Polyurethane elastomers synthesized from castor oil-based polyol exhibit favorable damping performance at elevated temperatures along with excellent mechanical properties. In this work, an isocyanate-terminated castor oil-based polyurethane prepolymer was synthesized using castor oil-modified polyol (DPH) and isophorone diisocyanate (IPDI). The monohydroxy groups in polypropylene glycol monobutyl ether (BPPG) were end-capped with IPDI to form pendant chain prepolymers (BPPG-PU), which were subsequently grafted onto the castor oil-based polyurethane prepolymer via a trimethylolpropane (TMP) crosslinker, producing room-temperature high-damping and high-elasticity polyether-type polyurethane elastomers (BPUE). The dynamic mechanical properties, thermal stability, microstructure, and mechanical performance of BPUE were comprehensively investigated. Results demonstrated that BPUE-0% (without pendant chains) exhibited outstanding performance: a T_g of 58.9 °C, a maximum damping factor (Tan δ_max) of 1.17, and a tensile strength of 11.50 MPa. With the incorporation of pendant chains, the effective damping temperature range broadened, and T_g shifted toward room temperature. While tensile strength decreased, elongation at break initially increased and then declined with higher pendant chain content. Among BPUEs with varying chain lengths, longer pendant chains significantly enhanced hydrogen bonding reinforcement. Overall, BPUE15-30% displayed optimal performance, achieving a T_g near room temperature (29.3 °C), an expanded damping temperature range of 63.9 °C, a damping factor of 0.91, and a maximum elongation at break of 407.29% while retaining a tensile strength of 2.94 MPa. Additionally, all BPUEs exhibited high transparency, with transmittance exceeding 80%.

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The development of electroconductive sodium alginate (SA)-based composite film has gained significant interest in tissue engineering because of its potential to enhance cell differentiation, proliferation, and tissue regeneration. This work uses green synthesized silver nanoparticles (AgNPs) as a filler to develop a conductive SA-based composite film SA/AgNPs (10, 20, and 30 mL) for tissue engineering. The green synthesized AgNPs were confirmed by UV spectra. The composite film was synthesized by a solution-casting method, and AgNPs were homogeneously dispersed in the composite film. Characterization of the films through XRD, FTIR, SEM, and electrical conductivity values demonstrated homogenous distribution of AgNPs. The antibacterial activity and mechanical properties were analyzed for the composite film. The electrical properties of the composite film promoted the alignment and functionality of the cells, making it a suitable material for applications in electrically responsive tissues, such as nerve, muscle, and cardiac tissues. As a result, the tensile strength increases by 83.92 MPa, and electrical conductivity increases by 1.36E−05 for the SA/AgNPs (20 mL) composite film. The release test of the composite film exhibited the cumulative release (%) is 13 for 12 h. The antioxidant of the SA/AgNPs (20 ml) composite film shows 75%. The swelling studies show that the films exhibited controlled water uptake, indicating stability in hydrated environments, and biodegradation analysis revealed the degradation rate, which is crucial for tissue engineering composite film.

Polyether amino silicone oil is frequently used as a softener in the field of textile printing and dyeing. Nevertheless, there are a number of issues with the current synthesis method, including its intricate workings and reliance on organic solvents. These issues have a negative impact on the ecological environment in addition to raising energy consumption. An original synthesis method was suggested in this study. Bola-type aminopropyl terminated polydimethylsiloxane ethoxylates (ATSE_n) with different ethylene oxide (EO) addition levels were created by reacting aminopropyl polydimethylsiloxane with ethylene oxide. The experimental findings demonstrated that the particle size of ATSE_n silicone emulsion first decreased and then increased as the EO segment increased. Correspondingly, there was a trend towards a decrease in the hardness of cotton fabrics treated with ATSE_n, followed by an increase. Cotton treated with ATSE_n is slightly less hydrophilic than commercially available block polyether amino silicone oil (TH), but has a slight advantage in the softness and elasticity of the fabric, while maintaining its coloring properties. Cotton fabrics treated with ATSE_n outperformed commercially available cotton fabrics treated with TH in terms of whiteness, softness, and stiffness retention, indicating that ATSE_n-treated cotton fabrics have good durability. This study opens up a new avenue for the synthesis of polyether aminosiloxane softeners.

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Integrating plastic wastes into a circular economy via catalytic pyrolysis presents a promising strategy. This study examines the catalytic pyrolysis mechanisms of plastics with different structures (LLDPE, PP, PET, PS, PAN, PU, AS, and ABS) over HZSM-5 zeolite using a fixed-bed reactor to clarify thermal decomposition behaviors, product pathways, and aromatic/coke formation. Structural differences in plastics show minimal impact on thermal decomposition termination temperatures. Polyolefins preferentially yielded light olefins, while plastics rich in phenyl-branched structures favored pyrolytic oil production. LLDPE outperforms others in light aromatics generation, achieving 71.53% BTEX selectivity in oil. Branched-chain hydrocarbons from plastics cracking tend to excessive cyclization, accelerating polycyclic aromatic hydrocarbons and coke precursor formation. In the catalytic upgrading of nitrogen-containing plastics (PAN, PU, AS, and ABS), HZSM-5 demonstrates a deficiency in denitrogenation capability. A significant amount of nitrogen-containing heterocyclic compounds was observed within the channels of the spent zeolite. While this facilitates the suppression of highly condensed PAHs, their persistent accumulation ultimately will restrict the catalytic performance of the zeolite. These findings provide valuable insights into the catalytic pyrolysis upgrading of structurally complex plastics.

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