A novel multifunctional isocyanate curing agent, denoted as TCI, was facilely synthesized via a one-step reaction involving 1,3,5-tris(2-hydroxyethyl)cyanuric acid and hexamethylene diisocyanate. The structural design of TCI incorporates a rigid triazine ring core and three additional urethane linkages, enabling the construction of high-performance crosslinked networks within glycidyl azide polymer (GAP)-based energetic elastomers. By systematically comparing TCI with the commercially available curing agent N100, the structure–property relationships were elucidated through a combination of curing kinetics, spectroscopic characterization, mechanical testing, and thermal analysis. TCI exhibits superior reactivity toward GAP, effectively compensating for the low reactivity of secondary hydroxyl groups. Structural characterization via XRD, SAXS, and FTIR demonstrated that TCI facilitates the formation of dense and stable hydrogen-bonding networks, which reduce the intermolecular chain spacing (0.424 nm for TCI–GAP vs. 0.436 nm for N100–GAP) and optimize the microphase separation behavior of the elastomer networks.Mechanical testing demonstrated that the tensile strength and elongation at break of TCI–GAP reach 1.74 MPa and 297.7%, respectively, representing increases of 95.5% and 163% over N100–GAP (0.85 MPa and 105.8%). Morphological analysis confirmed the presence of uniformly distributed crosslinking junctions and ductile fracture features in TCI–GAP, which are responsible for the improved load-bearing capacity and energy dissipation efficiency. Dynamic hydrogen-bonding interactions were identified as the key mechanism governing the mechanical and thermal performance of TCI-GAP. DMA and LF-NMR results indicated that TCI–GAP possesses higher storage modulus and more restricted segmental motion, leading to excellent thermomechanical stability. The novel TCI curing agent offers a facile and effective approach to simultaneously improve the mechanical strength, toughness, and thermal stability of GAP-based networks, showing great promise for applications in advanced solid propellants and energetic materials.

Nano-/micro-cellulose has attracted significant attention in advanced materials due to its cellulosic properties as well as the important hallmarks of nano-/micro-materials. However, current approaches for the preparation of them are predominantly limited to “top-down” strategies which yield mostly whisker-/fiber-like morphologies. Therefore, it is imperative to develop cellulose-based nano-/micro-materials with diversified architectures. Here, we report the preparation of cellulose nanosheets composed of cellulose nanofibrous network, using cellulose solution as the precursor, via a “bottom-up” strategy. Due to its excellent water dispersibility and stability, these cellulose nanosheets can be assembled to form cellulose hollow microspheres through an ice-melting-induced lyophilization technique. The property and application of the cellulose microspheres can be further expanded by preparing composite microspheres via co-assembling cellulose nanosheets with functional nanomaterials. This work not only provides a simple, mild, and green approach through a new type of “bottom-up” strategy which may shed light on the design and preparation of nano-/micro-materials, but also offers novel cellulose-based nano-/micro-materials which may find wide applications in various fields due to the distinct architectures.

In this study, we optimized the fabrication of bigel beads using a combination of orthogonal experiments and response surface methodology, with special focus on refining the gelling bath parameters and extrusion techniques. We systematically investigated the influence of the oil–water phase ratio on the properties of bigel beads and comprehensively evaluated their performance in simulated oral processing and gastrointestinal digestion. Our key findings were that the gelling bath composed of 75% ethanol and 0% Tween at 0 °C achieved the highest gelation rate (0.9882), while the optimal extrusion parameters that yielded the maximum sphericity (0.9751) were a pump rate of 0.13 mL/min, height 0.93 cm, and temperature 65 °C. The elevated oil-phase content significantly enhanced both the particle size and sphericity of the bigel beads, transformed the bigel type from O/W to bi-continuous, and increased the hardness and cohesiveness. Furthermore, a higher oleogel percentage exacerbated frictional interactions during simulated mastication, compromised structural stability, and consequently promoted the release of free fatty acids. These results provide novel insights into the fabrication protocols and structure–function relationships of bigel beads, contributing to the development of functional food materials.

To reduce the environmental impact of excessive fertilizer use, a biodegradable slow-release urea system was developed using poly(butylene succinate) (PBS) and polycaprolactone (PCL) via solution casting. Fourier transform infrared spectroscopy (FTIR) analysis indicated enhanced interfacial interactions between PBS and PCL at a mass ratio of 7:3, while scanning electron microscopy (SEM) observations revealed a dense and uniform film structure. The coated urea exhibited a typical two-stage release behavior with an initial burst followed by sustained release, significantly prolonging nitrogen release compared with pure urea, which dissolved completely within 10 min. In pakchoi preliminary growth evaluation experiments, the coated urea increased plant height by 16.48% and 16.94% relative to the pure urea and control groups, respectively, and reduced leaf chlorosis through continuous nitrogen supply. These results demonstrate that the PBS/PCL-coated urea system has strong potential for improving fertilizer utilization efficiency and promoting sustainable agricultural practices.

Hydrogels hold great potential for osmotic energy conversion due to their inherent low resistance, yet their application is limited by weak mechanical properties, low charge density, and unstable pore structures. To address these challenges, we propose a Hofmeister effect-mediated strategy to develop a tough and highly conductive nanofluidic hydrogel from carboxymethyl cellulose and polyvinyl alcohol. The resulting hydrogel exhibits a tensile strength of 17.7 MPa and achieves an osmotic power density of 12.6 W m-2 under a 50-fold salinity gradient, representing a 3402% and 368% increase over conventional hydrogels. This enhancement is attributed to the formation of a nanophase separation structure, where hydrophobic regions serve as physical crosslinks for excellent mechanical strength and swelling resistance, and hydrophilic channels function as "ion highways" for high ionic conductivity. Moreover, the highly charged nanopores induced by the salting-out effect boost ion selectivity. This design overcomes the traditional trade-off between mechanical stability and ion transport. Under a 500-fold salinity gradient, the power density reaches 38.4 W m-2, surpassing most state-of-the-art nanochannel membranes. This strategy demonstrates broad applicability across various hydrogel systems. This work offers a versatile, scalable route to fabricate high-performance nanofluidic hydrogel for efficient and durable osmotic energy conversion.

To improve the low-temperature mechanical properties of branched glycidyl azide polymer (BGAP) propellants, a flexible chain polymer, polyethylene oxide (PAO), was introduced into the BGAP binder system, and a series of BGAP/PAO elastomers with different blending ratios were prepared. The study focused on investigating the microscopic interaction of PAO with the binder cross-linking network, as well as its macroscopic impact on the properties of the elastomers. The results indicated that the crystallization behavior of PAO can introduce physical cross-linking points in the binder system, leading to an approximately eight-fold increase in tensile strength at both room and low temperatures. Furthermore, PAO enhances the mobility of chain segments, which, in turn, reduces the glass transition temperature of the binder system and improves elongation at low temperatures. Building upon these findings, the study further investigated the influence of PAO on the interaction between the BGAP binder system and solid fillers. A comparison was made between the structural and performance variations of BGAP/PAO elastomers and BGAP/PAO-based solid propellants. Ultimately, the optimal formulation of the BGAP/PAO binder system for solid propellants was determined. The results revealed that PAO crystallization reduces the interaction between the binder system and propellant fillers, leading to severe dewetting. This emphasizes the need to precisely control the amount of PAO added to fine-tune the low-temperature performance of the propellant.

The thermal decomposition performance of ammonium perchlorate (AP) in solid propellants directly affects the energy output and combustion efficiency of propulsion systems. However, its relatively high decomposition temperature and dispersed exothermic behavior limit its practical application. In this work, a CeO2/Co3O4-based catalyst with a three-dimensionally ordered macroporous (3DOM) structure was constructed and evaluated for the thermal decomposition of AP. Using the template assisted method, 3DOM CeO2/xCo3O4 (3DCe/xCo) catalysts with tunable Co2+/Ce3+ ratios were prepared and their catalytic behaviors toward AP decomposition were systematically investigated. Among them, 3DCe/0.9Co exhibited the best catalytic activity, lowering the high temperature decomposition temperature of AP by about 30% and markedly reducing the activation energy. Structural characterization, UV-vis DRS, VB-XPS, TG-IR, TG-MS, in situ XPS, and DFT calculations indicate that electron transfer from Co3O4 to CeO2 generates a built-in electric field and oxygen vacancies, which promote side-selective adsorption and activation of NH3 and HClO4. The interconnected 3DOM framework also facilitates mass transport and conversion of AP intermediates, and finally merges the two decomposition peaks of AP into a single exothermic peak. This work provides additional insight into the role of interfacial charge transfer and 3DOM CeO2/Co3O4 catalysts for AP thermal decomposition.

To enable real-time indication of food freshness and safety, a pH-responsive, color-changing food packaging film was developed. Blueberry anthocyanin (BA) was encapsulated with polyethylene oxide (PEO) using microencapsulation technology to produce Blueberry anthocyanin - polyethylene oxide microcapsules (BA-PEO). These microcapsules were then incorporated into a poly(butylene adipate-co-terephthalate) (PBAT)/thermoplastic starch (TPS) matrix to fabricate a biodegradable film capable of in situ monitoring of food freshness. Appropriate addition of BA-PEO enhanced the thermal stability and tensile strength of the PBAT/TPS films. At a BA-PEO content of 2 phr, the oxygen permeability coefficient reached a minimum value of 1.47 & times; 10- 15 cm3 center dot cm center dot cm- 2 center dot s- 1 center dot Pa- 1, representing a 20.3% reduction. However, the incorporation of BA-PEO increased both the water vapor transmission rate (WVTR) and water vapor permeability (WVP). At 4 phr BA-PEO, the WVTR and WVP were 115.20 g center dot(m2 center dot 24 h)-1 and 2.23 & times; 10-14 g center dot(cm2 center dot s center dot Pa)-1, respectively. A DE*ab value greater than 5 indicates that the color change is directly observable. Therefore, the potential of PBAT/TPS films filled with BA-PEO microcapsules is demonstrated in the field of intelligent food packaging materials.

Printable aqueous carbon nanotube (CNT) inks are promising for scalable, flexible, and wearable electronics, yet it remains challenging to simultaneously achieve high electrical performance, long-term dispersion stability, and reliable processability in water. A one-pot ternary deep eutectic solvent (TDES) pretreatment enables lignin depolymerization and functionalization with ammonium phytate/sulfate groups, followed by spontaneous self-assembly into P/N/S-containing lignin nanoparticles (PLNPs). The resulting PLNPs exhibit tunable particle sizes (from 24 nm to 100 nm) and high negative surface charge (up to -62.6 mV). PLNPs adsorb uniformly onto CNT surfaces without forming large aggregates. Molecular dynamics (MD) simulations reveal an "anchor-and-disperse" interfacial mechanism, in which PLNPs anchor on CNT surfaces with heteroatom-enabled noncovalent interactions, while surface charge and hydration provide electrosteric and steric stabilization that suppresses reaggregation. The PLNPs/CNT inks show pronounced shear-thinning and rapid thixotropic recovery, making them suitable for screen printing of conductive patterns on paper. The inks exhibit excellent colloidal stability (>100 days) and achieve conductivities up to 34.9 S·cm-1 without additional synthetic additives. Furthermore, cotton textiles can be dip-coated to fabricate wearable piezoresistive sensors capable of monitoring diverse human motions. This work provides a renewable, waterborne CNT ink platform for sustainable printed and wearable textile electronics.

Burning rate suppressants are essential for regulating the burning rate of solid propellants. The regulation mechanism of Gemini quaternary ammonium perchlorate salt (GQAPS) on the combustion performance of ternary hydroxyl-terminated polybutadiene (HTPB) propellants was investigated. The propellant's. burning rate was reduced to 5.47 mm s-1 at 7 MPa by adding 1 wt% GQAPS, indicating a superior burning rate inhibition efficiency of GQAPS. By constructing AP/GQAPS composites and analyzing their thermal decomposition properties, it was found adding 1 wt% GQAPS increased the activation energies of ammonium perchlorate (AP) during its low- and high-temperature decomposition stages by 11.86 kJ mol- 1 and 104.17 kJ mol- 1, respectively, and reduced the heat release during AP's high-temperature decomposition by 43.75 J g-1. TG-FTIR analysis showed that the infrared absorption peaks associated with GQAPS decomposition products disappeared. Moreover, the maximum absorption intensity ratio of NO2 to N2O in AP/GQAPS composites decreased by 52.2 % compared to pure AP. These results demonstrated that GQAPS decomposition products competitively consumed reactive oxygen species generated during AP decomposition, thereby altering the oxidation pathway of NH3 and synergistically inhibiting AP decomposition. However, excessive GQAPS diminished the inhibitory effect due to its inherent exothermic decomposition properties.

Nitro complexes (NCs) have been selected as combustion catalysts for propellants due to their synergistic behavior. However, NCs prepared by traditional methods suffer from poor dispersion and irregular shape, which limit their catalytic potential. Hence, a polymer-assisted anti-solvent crystallization (PAASC) strategy was developed to fabricate potassium barium hexanitronickelate (K2Ba[Ni(NO2)6], 2 Ba[Ni(NO 2 ) 6 ], PBHNN) crystals. In this method, emulsion particles created by mixing the solvent with the poor solvent serve as spherical templates. The particle size and monodispersity of PBHNN are controlled by PVP content. With 0.042 mol/L PVP, PBHNN were monodisperse with a particle size of 1.05 +/- 0.03 +/- 0.03 mu m, which showed the best catalytic behavior for increasing the exothermic amount of hexanitrohexaazaisowurtzitane (HNIW) by 100.6%. The high catalytic performance is due to the large specific surface area and improved contact efficiency. The in-situ TG-FTIR-MS test revealed that the procedure of PBHNN enhanced the pyrolysis of HNIW. The N-NO2 2 bonds of HNIW are weakened by the strong attraction of metal oxides to electrons, which accelerates the formation of NO2. 2 . Consequently, increased NO2 2 promotes subsequent oxidation reactions and improves the pyrolysis efficiency of individual HNIW. Therefore, the PAASC method is crucial for the fabrication of spherical monodisperse NCs with uniform particle size and high catalytic activity.

Copolymers of glycidyl azide polymer (GAP) and poly (caprolactone) (PCL) were obtained by introducing PCL molecular chains at both ends or side groups of GAP molecular chains, respectively. GAP/PCL elastomers were prepared via polyurethane curing reaction and compared with GAP/PCL elastomers prepared by physical blending, in order to clarify the relationship between microstructure and macroscopic properties. The results showed that no GAP and PCL phase separation was observed in the chemically bonded GAP/PCL elastomers. The elongation at break of the thermosetting GAP/PCL block copolymer elastomer increased significantly from 268% to 300% due to the increase in molecular weight between crosslinking points. The GAP/PCL graft copolymer, with its longer PCL segment length and higher segment mobility, formed microcrystalline domains within the elastomer, resulting in a significant improvement in tensile strength from 0.32 MPa to 1.07 MPa. In addition, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) revealed that the glass transition temperature of the GAP/PCL elastomer was 2.6 °C lower than that of the pure GAP elastomer, and the thermal stability was also enhanced.

Synthetic ester insulating oils are extensively utilized in power transformers due to their exceptional insulating properties, thermal stability, and environmental compatibility. The dissolved gas analysis (DGA) technique, which is employed to diagnose internal faults in transformers by monitoring the concentration and composition of dissolved gases in oil, is thought to be effective in detecting typical faults such as overheating and partial discharges in synthetic esters. However, owing to the significant differences in the properties of traditional mineral oil and synthetic esters, the existing DGA-based diagnostic methods developed for mineral oils cannot be directly applied to synthetic esters. A deep understanding of the microscopic processes occurring during the gas generation and diffusion of synthetic esters is an urgent necessity for DGA applications. Therefore, in this study, we systematically investigated the diffusion behavior of seven typical fault gases in synthetic ester insulating oils within a temperature range of 343–473 K using molecular dynamics simulations. The results demonstrate that H2 exhibits the highest diffusion capability across all temperatures, with a diffusion coefficient of 33.430 × 10−6 cm2/s at 343 K, increasing to 402.763 × 10−6 cm2/s at 473 K. Additionally, this paper explores the microscopic mechanisms underlying the diffusion characteristics of these characteristic gases by integrating the Free-Volume Theory, thereby providing a theoretical foundation for refining the fault gas analysis methodology for transformer insulating oils.

In the development of solid propellants, the inherent brittleness and high glass transition temperature (T-g) of poly (dicyclopentadiene) (PDCPD) pose significant challenges for achieving the desired high strength, ductility, and low T-g properties in binders. Poly (dicyclopentadiene) (PDCPD)-based composites using alpha-pinene as a polymeric plasticizer, is synthesized as a novel binder for solid propellants requiring high strength, ductility, and low T-g. Through frontal ring-opening metathesis polymerization (FROMP), PDCPD/alpha-pinene (PDA) blends were fabricated with alpha-pinene (5-50 mol%) acting as a physical plasticizer rather than a comonomer, overcoming its kinetic limitations in copolymerization. The incorporation of alpha-pinene significantly altered material properties, demonstrating an inverse correlation between alpha-pinene content and tensile strength (38.3-0.57 MPa) alongside a positive concentration dependence on elongation at break (91-556 %), while systematically reducing T-g from 160 degrees C to 27-94 degrees C. Dynamic mechanical analysis and tensile testing revealed maintained crosslinking density (12-21 repeat units between crosslinks) despite enhanced ductility, mainly attributed to alpha-pinene's free volume modulation within the polymer network rather than chain scission mechanisms. Rheological and thermal analyses showed alpha-pinene's dual role as an effective FROMP inhibitor, extending resin pot life (6-45 min) through reduced reaction heat release (299-381 W g(-1)) while enabling complete polymerization (>95 % conversion) via controlled frontal propagation. Thermal gravimetric analysis confirmed the composite's stability with three-stage degradation profiles, correlating alpha-pinene volatilization (100-305 degrees C) with theoretical content (2-40 % mass loss) and preserving PDCPD's crosslinked network integrity until structural carbonization (415-600 degrees C). The counterintuitive synergy between retained crosslinking and plasticization effects establishes alpha-pinene-modified PDCPD as a promising candidate for advanced propellant systems requiring tunable thermomechanical properties.

The formation of a burning rate gradient in gun propellant by flame-retardant treatment is one of the effective methods to achieve progressive combustion and thus improve the energy utilization efficiency. In order to reveal the effect of octa-(perfluorodecyl)-type polyhedral oligomeric silsesquioxanes (FPS-POSS) on the combustion performance of gun propellants, seven-perforated granular mixed nitrate ester gun propellants containing FPS-POSS of 0, 0.5, 1.0, and 1.5 wt % were prepared by the traditional semisolvent method. The chemical compatibility of FPS-POSS with the gun propellant components, the thermal decomposition properties, and the combustion characteristics of the gun propellants containing FPS-POSS were systematically investigated. The results show that FPS-POSS is well compatible with the components of the mixed nitrate ester gun propellant and does not affect the thermal stability of gun propellant but also reduces the residual weight of the gun propellant after thermal decomposition. Additionally, FPS-POSS can reduce the maximum burning pressure (P m) and burning rate (u) of the system and prolong the burning time (t m) for gun propellants to reach the maximum pressure, and this effect tends to increase with the increase of its content. There are two reasons for this. First, FPS-POSS has a lower chemical energy than energy-rich components such as nitrocellulose and nitroglycerin, and its addition to the gun propellant can affect the burning rate at the energy level. The second is that FPS-POSS not only traps reactive radicals in the gas phase by generating fluorine-containing radicals during combustion but also generates porous carbonaceous layer in the condensed phase to hinder the propagation of flames and gaseous products. It suggests that FPS-POSS is an excellent additive in the low burning rate region of gun propellants. When the content of FPS-POSS was 1.5 wt %, FPS-POSS decreased the P m of the system by 1.83%, increased the tm by 7.57%, and reduced the burning rate by 9.81%. High- and low-temperature experiments showed that FPS-POSS was favorable for reducing the temperature coefficients of gun propellants.

Designing highly active catalysts and constructing the interface between ammonium perchlorate (AP) and catalysts are effective strategies for achieving efficient thermal decomposition of AP, which is an urgent need for developing AP based composite solid propellants. Herein, we report an impregnation vacuum freeze-drying strategy to encapsulate AP in an independent three-dimensionally ordered macroporous (3DOM) CoFe2O4 (3D CFO) spinel, resulting in a novel 3D CFO encapsulated AP nanocomposite materials (AP-3DCNCs). The connected pores of 3D CFO provide a model structure for the growth of AP nanocrystals, while the impregnation vacuum freeze-drying strategy ensures the uniform distribution of AP crystals in pores, effectively achieving the size effect of AP nanocrystals (39.88 similar to 55.50 nm). By adjusting the loading capacity of the AP, the AP-3DCNCs configuration was effectively controlled. The thermal decomposition of AP-3DCNCs is greatly enhanced due to their unique configuration. The high-temperature decomposition temperature is significantly reduced by 180.06-141.78 degrees C, and the maximum equivalent heat release increased by 2.03 times. It can be foreseen AP-3DCNCs are attractive nanocomposites for the thermal decomposition of AP, and these results provide a convenient strategy for the preparation of transition metal-based composite catalysts with promising applications in the field of solid propellants.

The application of hexanitrohexaazaisowurtzitane (HNIW) as an oxidizer in solid propellants aligns with the pursuit of high-energy materials. However, the phase transformation behavior and high impact sensitivity of HNIW are its limitations. Due to the strong adhesion and mild synthesis conditions, polydopamine (PDA) has been employed to modify HNIW. However, the method suffers from a slow coating process and a non-ideal coating effect under short reaction time. Herein, oxygen-accelerated dopamine in situ polymerization coating method was developed. It was found that oxygen not only reduced the coating time but also contributed to forming a dense and uniform PDA layer. HNIW@PDA coated in oxygen for 6 h exhibited the most favorable performance, with a delay of 20.8 °C in the phase transition temperature and a reduction of 145.45% in the impact sensitivity. The -OH groups on the surface of PDA enhanced the interaction between HNIW and polymer binders, resulting in a 20.36% reduction in the dewetting percentage. The lower content of PDA in HNIW@PDA (1.17%) resulted in minimal variation in the heat of explosion for HNIW@PDA-based HTPB propellant (6287 kJ/kg) in comparison to HNIW-based HTPB propellant (6297 kJ/kg). Hence, HNIW@PDA-based propellants are expected to offer an alternative with promising safety and mechanical performance compared to existing HNIW-based propellants, thus facilitating the application of HNIW in high-energy propellants. This work presents a low-cost method for efficiently inhibiting the phase transformation of polycrystalline explosives and reducing the impact sensitivity. It also offers a potential approach to enhance the interfacial interaction between nitro-containing explosives and polymer binders.

Glycidyl azide polymer (GAP)-based polyurethane is an ideal elastomeric matrix for high-energy, low-smoke, and insensitive solid propellants. As the skeleton structure of GAP propellants, changes in the structure and properties of GAP elastomers during aging lead to the deterioration of propellant performance (especially in relation to mechanical properties), which causes safety risks. A high-temperature-accelerated aging experiment (70 °C) on a GAP elastomer was conducted. The evolution of the microstructure of the GAP elastomer system was analyzed by Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (NMR), and variations in the macroscopic properties were analyzed by the hardness test and the uniaxial tensile test. The experimental results showed that thermal aging of the GAP elastomer is a coupled process of multiple chemical reactions. The azide groups, urethane groups, and ether bonds were the weak links in the network structure, breaking during the aging process, and the crosslinking density rose and then decreased. Macroscopic properties also showed segmented changes. The aging process was divided into three stages: post-curing (stage one); when the crosslinked network began to break (stage two), and when the crosslinked network was destroyed (stage three). Changes in the microstructure and macroscopic properties were consistent. This work is of great significance for exploring the aging mechanism of GAP propellants and extending their storage life.

Developing efficient Ammonium Perchlorate (AP) thermal decomposition catalytic nanomaterials is necessary and challenging. To achieve this goal, three-dimensional ordered macroporous (3DOM) spinel structure CoFe2O4 (3DOM CoFe2O4) were prepared by using a simple impregnation method. The prepared 3DOM COFe2O4 has ordered and interconnected macroporous channels, which provide a large number of catalytic active site. After the addition of 2 wt% 3DOM CoFe2O4 catalyst, the THTD value of AP decomposition was reduced by 101.81 °C, and the decomposition activation energy was reduced from 178.42 kJ mol-1 to 134.21kJ mol-1. It can be foreseen that 3DOM CoFe2O4 is a very attractive AP thermal decomposition catalyst, which may open up new perspectives for the application of iron based materials as AP based solid propellant catalysts.