- Abstract：Protein stability is a critical factor that limits its application in biopharmaceuticals, clinical diagnostics, and industrial production. The inherent instability of proteins renders them susceptible to loss of activity and function under external environmental stresses, thus necessitating the development of novel stabilizers to improve protein stability. Inspired by sericin, we developed heterochiral poly-β-homoserine (β-HS) that combines resistance to enzymatic degradation, straightforward synthesis, and precise composition control, while exhibiting favorable in vitro safety profile. The β-HS exhibits remarkable stabilizing effects on horseradish peroxidase (HRP) and β-galactosidase (β-Gal) when subjected to elevated temperature and lyophilization, respectively. Our research indicates that β-HS stabilizes proteins by assisting in the maintenance of their conformation and preventing aggregation. Additionally, β-HS demonstrates stabilizing effects on proteins with diverse physicochemical properties. Therefore, this study suggests that the β-HS is a promising candidate for enhancing protein stability.Keywords：Silk sericin;Poly-β-homoserine;Protein protection;Stabilizer;Ring-opening polymerization0|0|0
Updated：2026-07-10 - Abstract：High-temperature polymer dielectrics are critically needed for advanced power electronics; however, their performance is often compromised by charge-transfer complexes (CTC) in aromatic polyimides. To overcome this limitation, we introduced an ultra-low loading of 5,10,15,20-tetra(4-aminophenyl) porphyrin (TAPP) as a multifunctional crosslinker into a polyimide (PI) matrix. TAPP simultaneously establishes covalent crosslinking and trap engineering, and its amino groups form a robust network with PI chains, whereas the porphyrin cycle acts as an efficient deep-level charge trap, effectively suppressing CTC formation and charge migration. The optimized PCPI films exhibited a tunable non-monotonic dielectric constant while maintaining a low loss. The PCPI-0.1 sample shows a significantly enhanced breakdown strength and achieves high discharge energy densities of 8.78, 6.09, and 4.97 J·cm−3 at 25, 150, 200 °C, respectively, while maintaining an efficiency above 85%. Remarkably, PCPI-0.1 delivered superior energy density compared to most high-temperature polymer dielectrics reported in the literature, coupled with excellent cycling stability and aging resistance. This work presents a strategy based on ultra-low-loading crosslinking that integrates structural modulation with deep-trap engineering, offering a viable pathway to high-performance all-organic dielectrics for extreme-condition applications.Keywords：Ultra-low loading;Covalent crosslinking;Trap engineering;Charge-transfer complexes;Energy storage;High-temperature0|0|0Updated：2026-07-10
- Abstract：Simultaneously optimizing the optoelectronic properties and the morphology of active layer is the key to high-performance polymer solar cells. Here, we present a novel materials-processing paradigm that incorporates a thermally activated delayed fluorescence (TADF) additive into the layer-by-layer (LBL) fabrication process to concurrently optimize nanoscale morphology and mitigate non-radiative recombination. We demonstrate that the TADF additive facilitates the formation of an ideal interpenetrating network during LBL film deposition, while its intrinsic TADF properties effectively reduce non-radiative voltage loss, enhance exciton lifetimes, and facilitate charge generation and transport. Devices fabricated with this synergistic strategy achieve both high short-circuit current density and open-circuit voltage, culminating in a remarkable power conversion efficiency exceeding 20%. This work not only provides an efficient and reproducible processing route for high-performance polymer solar cells (PSCs) but also opens a new avenue for addressing fundamental optoelectronic limitations through coordinated material design and processing innovation.Keywords：Polymer solar cell;Layer-by-layer;Thermally-activated delay fluorescence;Additive engineering;High-performance organic solar cell0|0|0Updated：2026-07-10
- Abstract：The synthesis of bottlebrush block copolymers (BBCPs) via ring-opening metathesis polymerization (ROMP) typically relies on exo-norbornene-terminated macromonomers to achieve high polymerization rates. However, norbornene derivatives synthesized via the Diels-Alder reaction were obtained as mixtures of exo and endo isomers, with the endo isomer predominating. This presents a significant challenge for the preparation of well-defined BBCPs from such mixtures because of the inherently low ROMP reactivity of endo-norbornene. Here, we demonstrate that polymerization kinetics are strongly influenced by the solvent, temperature, and configuration of the norbornene end group. By optimizing these parameters, the complete conversion of endo/exo macromonomer mixtures can be achieved within a short time, enabling the efficient synthesis of well-defined BBCPs. The resulting BBCPs exhibited self-assembly behavior comparable to those prepared from purely exo-norbornene-terminated macromonomers, forming structurally colored polymer microspheres that function as eco-friendly photonic pigments. This study provides an efficient and cost-effective strategy for the synthesis of BBCPs using commercially available norbornene derivatives.Keywords：Ring-opening metathesis polymerization;Bottlebrush block copolymer;Endo and exo isomers;Photonic microsphere0|0|0Updated：2026-07-10
- Abstract：Organic electrochemical transistors (OECTs) enable high-performance bioelectronics through their efficient ionic-electronic coupling, yet realizing a complete neuronal signal pathway that transduces environmental stimuli into spiking activity and synaptic memory remains a persistent system-level challenge. Here we demonstrate a neuron-inspired signal transduction pathway constructed entirely from OECTs, comprising a signal receptor, a spiking axonal module and a synaptic memory unit. System-level functionality is examined using a hardware-in-the-loop configuration based on direct analog signal transfer. The raw output photocurrent generated by the receptor drives the axonal oscillator, and the resulting voltage spikes subsequently modulate the synaptic device, without any algorithmic scaling or software-based amplification. This direct-drive regime preserves physical signal causality and reveals that the intrinsic signal levels of each functional block are naturally matched to the input requirements of the subsequent stage. Experimentally, receptor-induced spiking activity reliably gives rise to short-term synaptic plasticity under these unassisted conditions. Together, these results demonstrate the inherent inter-stage electrical compatibility of OECT-based devices and establish a rigorous experimental foundation for the future monolithic integration of fully organic neuromorphic systems.Keywords：Organic electrochemical transistors;Artificial neuron;Signal transduction;Hardware-in-the-loop configuration0|0|0Updated：2026-07-10
- Abstract：Epoxy resin (EP) is one of the most promising thermosetting resins used in engineering applications; however, its intrinsic drawbacks of poor abrasion resistance and flame retardancy limit its long-term application in harsh environments. In this study, to improve the comprehensive properties of EP, a prospective four-in-one strategy was proposed to prepare composites by rationally introducing multifunctional nanofillers. First, phosphorus- and nitrogen-enriched nickel/iron bimetallic phyllosilicates (PN-NiFePS) were facilely synthesized and subsequently incorporated into EP to prepare high-performance composites. The results indicate that PN-NiFePS nanoparticles display unique rice-grain-shaped morphologies with rough surfaces, as numerous PN-NiFePS nanosheets were vertically grown on the crystalline surface of the metal-organic framework. The chemically grafted P/N-containing pendant chains enabled well-bonded polymer-filler interfaces and homogeneous dispersion, significantly enhancing the mechanical properties. With the increase filler concentration, the wear rate exhibits a trend of initial decrease followed by subsequent increase, reaching a minimum of 1.19×10-6 mm3/(N·m) by adding 1% PN-NiFePS, which is 72% lower than pure EP. The incorporated PN-NiFePS endowed the composites with improved flame retardancy, leading to a steady increase in the limiting oxygen index and excellent self-extinguishing during combustion. This study provides an ingenious engineering strategy for constructing cross-function-integrated polymer composites suitable for harsh environments.Keywords：Nickel/iron bimetallic phyllosilicate;Four-in-one strategy;Cross-performance integration;Flame retardancy;Wet-sliding performance0|0|0Updated：2026-07-10
- Abstract：A fundamental prerequisite to effectively regulate the content of stereocomplex crystals (SCs) in poly(lactic acid) (PLA) is to elucidate the underlying mechanisms governing their formation. In this study, we established polymer blend systems with different chain segment mobility but similar initial segment miscibility based on dynamic Monte Carlo (MC) simulations. The SC fraction was found to be closely related to segment mobility in polymer blend systems during the crystallization process. The simulation results further indicated that polymer blend systems with stronger segment mobility exhibited higher segment miscibility during crystallization, resulting in the formation of more SCs. Therefore, it can be concluded that by increasing the segment mobility, segment miscibility can be enhanced, thereby improving the stereocomplexation ability.Keywords：Stereocomplex crystallization;Poly(lactic acid);Segment mobility;Segment miscibility1|0|0Updated：2026-07-10
- Abstract：We present a method for modifying metal organic frameworks (MOFs) surface functionalization using metal-free atom transfer radical polymerization (ATRP). Amino-functionalized zeolitic imidazolate frameworks-8 (ZIF-8-NH2) was synthesized at room temperature, and ZIF-8-Br was obtained by the reaction of the amino group in ZIF-8-NH2 with the acyl bromide group in 2-bromoisobutyl bromide (BIBB), thereby introducing secondary bromine groups onto the surface of ZIF-8-NH2. Then, ZIF-8-g-polymethyl methacrylate (ZIF-8-g-PMMA) hybrid materials were synthesized using ZIF-8-Br as an initiator via surface-initiated metal-free atom transfer radical polymerization (metal-free ATRP). The structural and morphological evolutions were monitored using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray powder diffraction (XRD) and scanning electron microscopy (SEM) measurements. Thermogravimetry (TG) analysis verified that ZIF-8-g-PMMA had excellent thermal stability, and the water stability test demonstrated that after grafting PMMA from the ZIF-8-NH2 surface, the hydrophobicity and water stability were improved significantly. The BET results proved that ZIF-8-g-PMMA had a high specific surface area of 835.24 m2/g. By immobilizing ZIF-8-g-PMMA hybrid material on fabrics, the modified fabrics exhibit excellent superhydrophobicity, with the water contact angle as high as 159.2o. Attributed to the synergistic effect of the micro- and nano-graded porous structure and low-surface-energy PMMA coatings, ZIF-8-g-PMMA hybrid material modified fabrics achieves highly efficient oil-water separation, with excellent adsorption effects on both light and heavy oils. Among them, the heavy oil can pass through the modified fabric within seconds with an oil-water separation efficiency of 96%. This method will further expand the scope of application of metal-free ATRP technology and MOFs materials.Keywords：Metal organic frameworks (MOFs);ZIF-8-NH2;Metal-free atom transfer radical polymerization (ATRP);Oil-water separation2|0|0Updated：2026-07-10
- Abstract：Rotaxanes are a class of mechanically interlocked polymers characterized by the sliding motion of ring molecules along a linear backbone. The dynamic behavior of a ring plays a critical role in determining its material properties. In this study, molecular dynamics simulations were performed to investigate the sliding dynamics of a ring on a rod-coil copolymer in rotaxane. We find that both the mean square displacement
$ {g}_{3} \left(t\right) $ $ {N}_{\mathrm{ring}} $ $ {g}_{3} \left(t\right) $ $ {N}_{\mathrm{ring}} $ Keywords：Molecular dynamics simulation;Sliding dynamics;Rod-coil copolymer13|3|0Updated：2026-07-06 - Abstract：Polymer crosslinked networks often face a fundamental trade-off between the mechanical robustness of covalent systems and the dynamic reversibility of supramolecular assemblies. Inspired by the hierarchical organization of biological extracellular matrix, where fibrous structures are reinforced by covalent crosslinking, we report a squaramide-directed cooperative assembly strategy that integrates one-dimensional (1D) supramolecular nanofiber formation with covalent macromolecular architecture to construct hierarchical polymer networks. Telechelic macromolecules were designed by tethering orthogonally arranged squaramide–amide hydrogen-bonding motifs to polydimethylsiloxane (PDMS) spacers. In the model system, these motifs undergo cooperative nucleation-elongation assembly into long-range nanofibers, while comparison with a urea analogue reveals enhanced intermolecular binding and assembly stability arising from the squaramide motif. Covalent integration of the assembling units transforms discrete nanofibers into microphase-separated networks with increased thermal stability and storage modulus. This work establishes a molecular design principle linking cooperative self-assembly with hierarchical polymer network formation and macroscopic mechanical performance.Keywords：Cooperative assembly;Squaramide;Telechelic polymers;Hydrogen bonding;Hierarchical polymer networks17|4|0Updated：2026-07-06
- Abstract：Composite solid-state electrolytes (CSEs) with excellent flexibility and high safety hold great potential for high performance lithium batteries. However, its low room temperature ionic conductivity and transfer number have plagued its practical application. In this work, local Li diffusion was tailored by the synergetic effect of halloysite nanotubes (HNTs) and high-entropy ZIF in a polyvinylidene fluoride/LITFSI/Li6.85La2.95Yb0.05Zr1.85Ta0.15O12 matrix. The anchoring of TFSI– anions by the rich open metal sites in HE-ZIF and the inner positively wall in HNT, combined with the continuous diffusion pathway of Li+ built by the negatively surface of HNT, distinctly enhances the ionic conductivity and transfer number of the electrolyte. A high ionic conductivity (1.06×10–3 S·cm–1 at 30 °C) and high Li+ transference number (0.86) were achieved in PLLH-HE. The lithium symmetric battery (Li//PLLH-HE//Li) exhibited excellent interfacial compatibility and a high critical current density (CCD, 2.38 mA·cm–2). A lithium metal battery assembled with LiFePO4 (LFP) cathodes exhibited a high discharge specific capacity of 141 mAh·g–1 after 400 cycles at 0.5 C, while the cell assembled with LiNi0.8Co0.1Mn0.1O2 (NCM811) also delivered a high discharge specific capacity of 140.1 mAh·g–1 at 1 C after 600 cycles. This work reveals the critical role of local Li diffusion and provides a general method for enhancing the electrochemical properties of CSEs for solid state batteries.Keywords：Composite solid-state electrolytes;Lithium-ion conductivity; Transfer number;Halloysite nanotubes;High-entropy ZIF;Synergetic effect12|4|0Updated：2026-07-06
- Abstract：Bioinspired smart surfaces enable reversible regulation of surface wettability, which is increasingly important for the advancement of surface and interface science. Herein, a novel fluorine-free photoresponsive azo-copolymer was rationally designed and synthesized via a molecular engineering strategy involving the synergistic integration of photoresponsive azobenzene moieties and low-surface-energy organosilicon segments. A facile solution dip-coating method was employed to construct photoresponsive smart fabric surfaces. Benefiting from the excellent reversible trans-cis isomerization of the azobenzene moieties within the azo-copolymer, the resulting coating achieved a notable surface energy variation of up to 32.75 mN·m–1. The as-prepared smart fabrics exhibited rapid, reversible wettability switching between high hydrophobicity (water contact angle of about 135°) and superhydrophilicity (0°) within 120 s under alternating UV and visible light irradiation. Meanwhile, the smart fabric surfaces exhibited outstanding chemical and mechanical robustness, enabling resistance to harsh environmental conditions, repeated abrasion tests, and various mechanical deformations, such as stretching, curling, and folding. More importantly, as a proof-of-concept demonstration, diverse rewritable wettability patterns were conveniently fabricated on a smart fabric surface via selective light exposure. This simple and effective strategy, together with the as-developed smart surfaces, holds great promise for application in information storage, biosensors, and microreactors.Keywords：Azo-copolymer;Smart fabrics;Photoswitchable wettability;Patterned surface;Fluorine-free9|1|0Updated：2026-07-06
- Abstract：The non-equilibrium dynamics of solvent evaporation and polymer diffusion induce vertical crystallization differences in the donor film, which pose great challenges to the precise control of the ideal vertical phase morphology in pseudo-planar heterojunction (PPHJ) organic photovoltaics (OPVs). In this study, the Peclet number (Pe) was first proposed as a predictive parameter to evaluate the correlation between solvent evaporation and the vertical gradient distribution morphology of the active layer during the film-forming process. This further directs the regulation of the hierarchical aggregation structure and vertical crystallization behavior of the polymer donor, thereby inducing ordered donor/acceptor interpenetration and ultimately achieving the construction of active layers with controllable heterojunction architectures. Depth-dependent light absorption spectroscopy and in situ depth-dependent fluorescence intensity measurements confirmed that Pe is about 1 can induce vertical crystallization differences in various polymer donors to form a PPHJ active layer with an ideal vertical gradient distribution morphology. Consequently, the toluene-processed PPHJ device achieved competitive power conversion efficiencies of 20.07%/16.86% (0.04/16.94 cm2) via blade coating technology.Keywords：Organic photovoltaics;Solvent evaporation;Polymer diffusion;Herarchical aggregation;Peclet number57|2|0Updated：2026-07-02
- Abstract：The flame-retardant monomer PG (P) was synthesized from diethylphosphinic acid and glycidyl methacrylate (GMA). Simultaneously, the phosphorus-containing flame-retardant monomer, TAEP (T), was synthesized from phosphorus oxychloride and 2-hydroxyethyl acrylate. A 50 µm thick transparent UV-cured coating, designated MAAR-P8T4, was successfully constructed on 0.5 mm thick polycarbonate (PC) films by blending PG and TAEP with melamine acrylate resin (MAAR). The fabricated coating demonstrated a high transmittance of 91.9% in the visible-light spectrum. The incorporation of monofunctional PG effectively regulated the system viscosity and mitigated curing shrinkage stress. Furthermore, the synergistic action of phosphorus in different valence states and nitrogen from MAAR imparted a dual gas-phase-condensed phase flame-retardant mechanism to the coating, enabling the PC substrate to attain a V-0 rating in the UL-94 vertical burning test. This research indicates that the MAAR-P8T4 coating engineered via molecular design and component optimization concurrently overcomes the limitations of PC, namely its low surface hardness and inherent flammability. A straightforward and efficient preparation strategy provides a practical approach for transparent flame-retardant coatings for electronic and electrical applications.Keywords：Synergistic flame retardant system;UV-curable coatings;Transparent coating;Flame retardancy;Polycarbonate18|14|0Updated：2026-07-02
- Abstract：Silk fibroin hydrogels frequently exhibit insufficient mechanical strength for biomedical applications. Conventional enhancement strategies often rely on toxic crosslinkers or nondegradable components, thereby compromising biocompatibility and biodegradability. Recently emerged organic solvent-based methods represent an advance, but their associated environmental toxicity remains a concern. In this work, we present a novel thermal oscillation strategy for fabricating high-strength silk fibroin hydrogels exclusively from all-aqueous silk fibroin solutions, eliminating the need for toxic chemicals or non-degradable materials. The resulting hydrogels exhibit outstanding mechanical properties, tensile strength of 2.6 MPa, elongation rate of 152.6%, and toughness of 3.0 MJ/m3, which not only surpass the organic solvent-derived silk fibroin hydrogels but also rival the dual-crosslinked, double-networked or composite systems. The silk fibroin hydrogels also exhibit a minimal swelling ratio, outstanding long-term integrity, and excellent biocompatibility. The robust, biocompatible, and biodegradable silk fibroin hydrogels are promising for biomedical applications such as load-bearing tissue scaffolds, long-term implantable drug delivery systems, and durable wound dressings.Keywords：Silk fibroin;Hydrogel;Strength18|15|0Updated：2026-07-02
- Abstract：Water/alcohol-soluble organic luminophores are a crucial subclass of luminescent materials that uniquely enable biomedical applications and eco-friendly optoelectronics that are inaccessible to their conventional hydrophobic counterparts. This review systematically outlines two fundamental strategies for achieving this essential solubility: chemical modification through covalent functionalization and physical encapsulation via supramolecular assembly. We analyzed the inherent trade-offs of each approach in terms of stability, luminescence properties, and synthetic complexity. Subsequently, we trace the evolution of these design principles across three major classes of luminophores: fluorescent, phosphorescent, and thermally activated delayed-fluorescence systems. Furthermore, we highlight their transformative applications in bioimaging, biosensing, anti-counterfeiting, and sustainable electronics. By mapping these strategies and applications, this review underscores how solubility design paves the way for broader utilization of organic luminophores in cutting-edge luminescent technologies.Keywords：Water/alcohol-soluble;Organic luminophores;Fluorescent;Thermally activated delayed fluorescence;Luminescent technologies9|2|0Updated：2026-07-02
- Abstract：Conjugated polymers are indispensable materials in organic optoelectronics. Living chain-growth polymerization has emerged as a promising strategy for synthesizing conjugated polymers with narrow polydispersity indices. To date, the majority of living chain-growth polymerization protocols have relied on Kumada-type cross-coupling reactions using aryl halides as monomers. Herein, we developed a nickel-catalyzed living chain-growth polymerization method based on carbon–sulfur bond activation, employing aryl sulfides as monomers, which enabled the synthesis of poly(3-hexylthiophene) (P3HT) with a regioregularity exceeding 95%. Kinetic studies confirmed the chain-growth mechanism of the polymerization, while steric hindrance and electronic effects were found to play important roles in regulating the polymerization behavior.Keywords：C―S bond activation;Living chain-growth polymerization;Aryl sulfides;Poly(3-hexylthiophene)13|4|0Updated：2026-07-02
- Abstract：Polymer microneedles (MNs) have emerged as promising next-generation transdermal drug delivery platforms owing to their noninvasive nature and high delivery efficiency. Conventional fabrication strategies for polymer MNs mainly rely on mold-assisted vacuum casting or hot pressing. However, these approaches often fail to simultaneously achieve rapid fabrication and mild processing conditions, which are particularly critical for the fabrication of temperature-sensitive drug-loaded MNs. Herein, we report a vacuum-assisted pressing strategy for MN fabrication based on O-carboxymethyl chitosan (CMCA) and natural polyphenol protocatechuic acid (PCA) supramolecular composite slurries. This method enables MN production under significantly reduced processing times (<12 h) and mild thermal conditions (50 °C). Viscoelastic supramolecular composite slurries can be obtained by precisely tuning the polymer-to-polyphenol ratio, which is highly compatible with vacuum-assisted pressing in MNs molding. The resulting polymer-polyphenol supramolecular composites exhibit robust mechanical properties, with a fracture stress of 0.5 MPa and a toughness of 1.31 MJ·m–3. Notably, supramolecular MNs demonstrated a high fracture force of up to 1.08 N per needle, indicating sufficient mechanical integrity for transdermal insertion. This fabrication strategy offers a viable route for low-cost, scalable, and mild MN fabrication, highlighting its strong potential for practical and commercial applications.Keywords：Microneedle fabrication;Polyphenol;Supramolecular interactions;Mechanical robustness11|11|0Updated：2026-07-02
- Abstract：In this study, the weathering resistances of glass-fiber-reinforced polymer G1 and two types of carbon-fiber-reinforced polymers, C1 and C2, were studied after six years of outdoor exposure in various climatic zones. Interlaminar shear tests were conducted at strain rates that differed by four orders of magnitude, and dynamic mechanical analyses of these materials were performed both initially and after weathering. Thermal activation analysis of the interlaminar shear test results was used to determine the thermodynamic strength parameter, Psh and durability of the materials. It has been demonstrated that the greatest reduction in the service life of the materials occurs after exposure to the hot and humid climate of Gelendzhik.Keywords：Fiber-reinforced polymers;Weathering;interlaminar shear;Thermal activation analysis;Durability8|23|0Updated：2026-07-02
- Abstract：In this study, unique conductive gratings were constructed in polyurethane (PU) foams to achieve tunable electromagnetic shielding. First, a mold enabling region-selective silver plating was fabricated through model design and 3D printing technology. Second, PU foam was placed inside the mold to create controllable exposure regions. Third, a region-selective silver plating process was achieved by exploiting this localized exposure, thereby successfully constructing conductive grating composite foams (grating-Ag/PDA@PU). The effects of the grating number, arrangement pattern, spacing, and incident angle of electromagnetic waves on the electromagnetic interference shielding effectiveness (EMI SE) were systematically investigated, revealing the structure-property relationship between shielding performance and grating geometric parameters. The results indicate that the EMI SE values of a single-layer conductive grating are positively correlated with the number of gratings. For a multilayer conductive grating, staggered parallel arrangements exhibit superior shielding performance compared to simple parallel arrangements. Appropriately increasing the spacing between gratings helps reduce mutual electromagnetic coupling, thereby enhancing the overall EMI SE values. It was also found that a nondestructive electromagnetic shielding switch could be realized simply by flipping the sample. Specifically, the EMI SE values changing from 3.53 dB to 34.04 dB can be achieved by simply flipping the foams. This study provides new insights into the design and fabrication of tunable conductive gratings for use in electromagnetic shielding switches.Keywords：Conductive grating;Polyurethane foam;Region-selective silver plating process;Electromagnetic shielding switch12|15|0Updated：2026-07-02
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