Macromolecular Rapid Communications最新文献

Hypoxic diabetic foot ulcers (HDFUs) pose a challenging chronic condition characterized by oxidative stress damage, bacterial infection, and persistent inflammation. This study introduces a novel therapeutic approach combining ergothioneine (EGT), luteolin (LUT), and quaternized chitosan oxidized dextran (QCOD) to address these challenges and facilitate wound healing in hypoxic DFUs. In vitro, assessments have validated the biosafety, antioxidant, and antimicrobial properties of the ergothioneine-luteolin-chitin (QCOD@EGT-LUT) hydrogel. Furthermore, near-infrared II (NIR-II) fluorescence image-guided the application of QCOD@EGT-LUT hydrogel in simulated HDFUs. Mechanistically, QCOD@EGT-LUT hydrogel modulates the diabetic wound microenvironment by reducing reactive oxygen species (ROS). In vivo studies demonstrated increased expression of angiogenic factors mannose receptor (CD206) and latelet endothelial cell adhesion molecule-1 (PECAM-1/CD31), coupled with decreased inflammatory factors tumor necrosis factor-α (TNF-α) and Interleukin-6 (IL-6), thereby promoting diabetic wound healing through up-regulation of transforming growth factor β-1 (TGF-β1).

To enhance the photoluminescence (PL) of unconventional luminescent compounds, particularly their persistent room temperature phosphorescence (p-RTP) performance, compressing the powder into tablets has been demonstrated as a viable approach. Nevertheless, the alterations in the emission capability of PL in compacted tablets have not been comprehensively investigated. In this study, four polyacrylamide (PAM) with controllable molecular weight (MW) are fabricated from powder to tablets, and their PL emission properties are thoroughly examined and compared with corresponding powders to elucidate the emission mechanism. As MW increases, both PL and p-RTP emissions of the tablets gradually intensify, exhibiting significant enhancement compared to the corresponding powder while retaining the characteristic blue shift. Through small angle X-ray scattering (SAXS), construction of molecular models for tablets, detailed analysis of molecular interactions, and theoretical calculations are conducted to reasonably explain these emission phenomena using clustering-triggered emission (CTE) and average packing density promoted emission (PDE) mechanisms. These findings not only advance the understanding of nonconventional luminogens' emission mechanisms but also offer new insights for preparing nonconventional luminescent polymers with controllable p-RTP emission performance.

The production of materials based on fossil resources is yielding more sustainable and ecologically beneficial methods. Vegetable oils (VO) are one example of base materials whose derivatives rival the properties of their petro-based counterparts. Gaps exist however and one way to fill them is by employing sol-gel processes to synthesize organic-inorganic hybrid materials, often derived from silane/siloxane compounds. Creating Si─O─Si inorganic networks in the organic VO matrix permits the attainment of necessary strength, among other property enhancements. Consequently, many efforts have been directed to optimally achieve organic-inorganic hybrid materials with VOs. However, compatibilization is challenging, and desirable conditions for matching the inorganic filler in the organic matrix remain a key stumbling block toward wider application. Therefore, this review aims to detail recent progress on these new hybrids, focusing on the main strategies to polymerize and functionalize the raw VO, followed by routes highlighting the addition of the inorganic fillers to obtain desirable composites.

Polymer cubosomes (PCs) are a recent class of self-assembled nanostructures with great application potential due to their high porosity and surface area. Currently, most reported PCs consist of polystyrene block copolymers (BCPs), for which self-assembly parameters are rather well understood. Changing the block chemistry would be desirable to introduce more functionality; however, knowledge of adapting the self-assembly process to new chemistries remains limited. This work, reports on synthesizing poly(ethylene oxide)-block-poly(4-acetoxystyrene) and its copolymers with styrene, and provide conditions for their self-assembly into PCs with high yield and high inner order. It is shown that the polarity of the starting solvent toward the corona block allows tuning of the final morphology by controlling the corona volume and packing parameter.

This study presents a novel approach to developing eco-friendly dye-sensitized solar cells (DSSCs) using natural and renewable materials for gel polymer electrolytes (GPEs), reducing reliance on unsustainable solvents. Water is added to polar aprotic solvents, specifically ethylene carbonate/propylene carbonate (EC/PC), across various mass fractions (0:100 to 100:0). An amphiphilic hydroxypropyl cellulose (HPC) natural polymer is employed to formulate GPEs within this water-EC/PC cosolvent system, achieving successful gelation up to 50:50 mass fractions. Incorporating water reduced the gel strength and viscosity of the GPEs. Water acted as a plasticizer, enhancing the polymer chains mobility, and creating a more flexible and permeable structure. This increased ion diffusion coefficients and ion mobility, resulting in a maximum ionic conductivity of 18.17 mS cm^-1. The highest efficiency achieved in DSSCs using these GPEs is 5.81%, with elevated short-circuit current density and reduced recombination losses. However, some compositions experienced syneresis, affecting their stability. The GPE with a 40:60 mass fraction exhibited superior long-term stability because it is free from syneresis, though it achieved a lower efficiency (4.83%), making it the best-performing sample. This work demonstrates the feasibility and benefits of using gel polymer electrolytes in an aqueous system, improving DSSC efficiency and sustainability.

Additive manufacturing of transition metal sulfides (TMS) enables the creation of complex 3D structures, significantly expanding their applications. However, preparing 3D-structured TMS remains challenging due to difficulties in developing suitable inks. In this study, a supramolecular micelle hydrogel as the ink to fabricate 3D-structured TMS is utilized. Initially, the hydrogels are printed and infused with metal salt solutions to stabilize the structures, which are then calcined to convert into miniaturized 3D-TMS replicas. The micellar hydrogels crosslink via hydrophobic interactions, with sodium dodecyl sulfonate (SDS) micelles providing both a hydrophobic environment and sulfur sources. During calcination, the decomposed sulfur precursors coordinate with metal ions to form various TMS, including FeS₂, Cu₂S, Ni₃S₂, and Co₉S₈, along with several metal sulfides like PbS and SnS. Additionally, the method also allows for the preparation of transition metal dichalcogenides such as MoS₂ and WS₂. The formation mechanism is demonstrated using Ni₃S₂ as an example which exhibits notable catalytic activity in oxygen evolution reactions (OER) and hydrogen evolution reactions (HER). Given its simplicity and versatility, this dynamic micellar hydrogel-derived strategy offers a promising pathway for creating advanced TMS materials.

The suboptimal ionic conductivity of commercial polyolefin separators exacerbates uncontrolled lithium dendrite formation, deteriorating lithium metal battery performance and posing safety hazards. To address this challenge, a novel organic-inorganic composite separator designed is prepared to enhance ion transport and effectively suppress dendrite growth. This separator features a thermally stable, highly porous poly(m-phenylene isophthalamide) (PMIA) electrospun membrane, coated with ultralong hydroxyapatite (HAP) nanowires that promote "ion flow redistribution." The synergistic effects of the nitrogen atoms in PMIA and the hydroxyl groups in HAP hinder anion transport while facilitating efficient Li⁺ conduction. Meanwhile, the optimized unilateral pore structure ensures uniform ion transport. These results show that the 19 µm-thick HAP/PMIA composite separator achieves remarkable ionic conductivity (0.68 mS cm^-1) and a high lithium-ion transference number (0.51). Lithium symmetric cells using HAP/PMIA separators exhibit a lifespan exceeding 1000 h with low polarization, significantly outperforming commercial polypropylene separators. Furthermore, this separator enables LiFePO₄||Li cells to achieve an enhanced retention of 97.3% after 200 cycles at 1 C and demonstrates impressive rate capability with a discharge capacity of 72.7 mAh g^-1 at 15 C.

The structure-properties relationships of sustainable materials derived from biomass-based monomers are investigated, focusing on hybrid styrene/terpene-based copolymers with blocky microstructures, such as β-myrcene- and β-ocimene-styrene copolymers. The samples show complex glass transition dynamics, as evidenced by the physical aging experienced by the amorphous phase in styrene-rich copolymers. The tendency of styrene- and terpene-rich sequences to give heterogeneous morphologies with correlation strength extending over 10-40 nm is outlined, through small-angle X-ray scattering analysis. A new class of terpene-based hybrid systems, holding promise for applications in surface coating technologies, is identified.

4D printing magneto-responsive shape memory polymers (SMPs) using biodegradable nanocomposites can overcome their low toughness and thermal resistance, and produce smart materials that can be controlled remotely without contact. This study presented the development of 3D/4D printable nanocomposites based on poly (lactic acid) (PLA)-poly (butylene adipate-co-terephthalate) (PBAT) blends and magnetite (Fe₃O₄) nanoparticles. The nanocomposites are prepared by melt mixing PLA-PBAT blends with different Fe₃O₄ contents (10, 15, and 20 wt%) and extruded into granules for material extrusion 3D printing. The morphology, dynamic mechanical thermal analysis (DMTA), mechanical properties, and shape memory behavior of the nanocomposites are investigated. The results indicated that the Fe₃O₄ nanoparticles are preferentially distributed in the PBAT phases, enhancing the storage modulus, thermal stability, strength, elongation, toughness, shape fixity, and recovery of the nanocomposites. The optimal Fe₃O₄ loading is found to be 10 wt%, as higher loadings led to nanoparticle agglomeration and reduced performance. The nanocomposites also exhibited fast shape memory response under thermal and magnetic activation due to the presence of Fe₃O₄ nanoparticles. The 3D/4D printable nanocomposites demonstrated multifunctional multi-trigger shape-memory capabilities and potential applications in contactless and safe actuation.

Porous polymer composites (PPC) have developed rapidly recently, which are widely used in various industrial fields. Viscoelastic damping is an important behavior of porous polymer composites, and it can determine the sound absorption for noise reduction applications. This review has mainly covered the viscoelastic damping and sound absorption of porous polymer composites. Different fabrication approaches of porous polymer composites are gathered. The mechanism of viscoelastic damping behavior is described, and also the sound absorption properties. Followed by the introduction of enhanced sound absorption of viscoelastic damping porous polymer composites, including the incorporation of fillers, microstructures modification, combination with nanofibrous materials, and multilayer configuration, etc. The incorporated fillers can effectively adjust the interfacial area in composites, and obtain desired bonding conditions. Microstructures modification is an effective tool to improve the morphologies of both polymer matrix and fillers, which can be achieved by chemical treatment and surface coating. The combination with lightweight nanofibrous layer can increase the low frequency absorption. The configuration of multilayer composites can improve both acoustical and mechanical properties for engineering applications. It is hoped that this comprehensive review is benefit for the promising development of porous polymer composites in related fields.