ABSTRACT Rubber sealing components in power equipment degrade during long‐term thermal–air aging, which threatens reliability. This study investigates the aging behavior of three representative sealing materials: fluorocarbon rubber (FKM), ethylene propylene diene monomer (EPDM), and nitrile rubber (NBR). Accelerated thermal aging tests are performed at temperatures selected according to material stability (FKM: 150°C–250°C; EPDM and NBR: 95°C–150°C) for 0.5–14 days. Surface morphology, mechanical properties (hardness, stress–strain response, and compression set), and physical properties (density, volume, and mass) are characterized; DMA and TGA are used to evaluate the evolution of thermal properties. All three materials show degradation, with different severities. FKM exhibits only minor changes in hardness, density, and compression set. NBR shows the most pronounced deterioration: after 14 days at 150°C, hardness increases by 31.1%, accompanied by marked volume shrinkage and mass loss. EPDM displays intermediate behavior. An Arrhenius‐based kinetic model based on compression‐set data is established to predict service life, supporting material selection and preventive maintenance for power equipment.

ABSTRACT Cellulose, a renewable and biodegradable polymer, can be converted into 2,3‐dialdehyde cellulose (DAC) with increased reactivity for use in functional materials. DAC formation is commonly achieved using periodate oxidation under conventional heating, although this approach suffers from long reaction times and low energy efficiency. Microwave‐assisted DAC formation has been developed, but generally involves long reaction times and high power; therefore, optimization of DAC synthesis under low‐energy and short‐time conditions has not been widely studied. This study synthesized DAC from microcrystalline cellulose (MCC) via low‐energy microwave‐assisted periodate oxidation, aimed at reducing energy consumption while preserving effective aldehyde group production. The results showed that DAC formation was achieved under all experimental conditions, with the optimal condition at 700 W for 1.5 h, yielding the highest aldehyde content of 77%, which was significantly higher than that obtained by conventional heating at the same reaction time. FTIR, XRD, and SEM analyses confirmed structural alterations of cellulose, while thermal analysis indicated reduced thermal stability accompanied by increased char residue, attributable to hemiacetal formation. This study demonstrates that low‐energy microwave‐assisted periodate oxidation is an efficient and sustainable approach for DAC synthesis and supports the development of advanced cellulosic materials using energy‐efficient processes.

ABSTRACT Compressive loading–unloading and oligo cyclic tests were performed on neat epoxy and GO‐epoxy nanocomposites containing 0.1 and 0.5 wt% graphene oxide (GO) to investigate the effects of GO content and strain rate on modulus evolution and damage development. The tests targeted the elastic, yield, and viscoplastic regimes while minimizing low‐cycle fatigue. The strain rate sensitivity factor and damage parameter, which are defined considering the initial elasticity modulus and modulus during unloading, were calculated for neat epoxy and GO‐epoxy nanocomposites. Rate‐dependent compression experiments indicate that the GO‐epoxy nanocomposite with 0.1 wt% GO exhibits approximately 2.5 times higher strain rate sensitivity in this range compared to the nanocomposite containing 0.5 wt% GO. The results indicate that in neat epoxy, the modulus decreases at the second cycle but recovers in later cycles due to cyclic hardening and polymer chain alignment. In contrast, GO‐reinforced nanocomposites consistently show higher unloading modulus than neat epoxy. During oligo cyclic loading, neat epoxy and GO‐epoxy nanocomposites exhibit linear loading and nonlinear unloading behavior. Stress–strain responses are nearly identical between monotonic and oligo cyclic tests, except for slightly higher stress in the final cycle of cyclic loading, indicating minimal influence of short‐term loading history on mechanical behavior.

ABSTRACT This study investigates the effects of polytetramethylene ether glycol (PTMEG) plasticizer and multi‐walled carbon nanotubes (MWCNTs) on the physical, mechanical, thermal, structural, and electrical properties of poly(lactic acid) (PLA)–based composites. PLA was first blended with varying PTMEG contents (10–20 wt%), followed by incorporation of surface‐modified MWCNTs (0.25–1 wt%). Miscibility evaluation using Flory–Huggins interaction parameters confirmed near‐miscible PLA/PTMEG behavior (χ < 0.5). Differential scanning calorimetry showed a significant reduction in glass transition temperature ( T g ) from 56°C in neat PLA to 24°C at 20 wt% PTMEG, accompanied by increased crystallinity. Tensile testing revealed striking ductility improvements, with elongation at break increasing up to 82‐fold, though strength and modulus decreased due to plasticization. Incorporation of MWCNTs improved modulus and tensile strength but reduced ductility; 0.75 wt% MWCNT yielded the optimal balance, with a 20‐fold increase in elongation compared to virgin PLA and a modulus 4.3× higher than plasticized PLA. XRD confirmed enhanced α‐phase crystallization, supported by FE‐SEM images showing uniform CNT dispersion with limited aggregation. Electrical testing revealed a ~10 6 ‐fold reduction in resistivity at 1 wt% MWCNT, indicating formation of conductive pathways. Overall, combined PTMEG and MWCNT addition significantly improved toughness, crystallinity, and electrical performance of PLA, providing a promising route for advanced biodegradable composite applications.

ABSTRACT This work aimed to enhance the flame retardancy, smoke suppression, and mechanical properties of a low‐temperature‐resistant plasticized polyvinyl chloride/hydrogenated nitrile‐butadiene rubber (PVC/HNBR) multifunctional composite. Magnesium hydroxide (MH) filler was modified via dry surface treatment using stearic acid, titanate coupling agent, or silane coupling agent (SC). The modified MH was incorporated into PVC/HNBR via two methods to investigate the composite's combustion behavior, mechanical properties, and low‐temperature resistance. Results demonstrated that the composite prepared by first blending SC‐modified MH with HNBR, followed by mixing with plasticized PVC, exhibited optimal overall performance. This PVC/HNBR composite achieved a limiting oxygen index of 33.9%, a smoke density rating of 26.21%, a tensile strength of 11.30 MPa, an elongation at break of 415%, and a glass transition temperature as low as −23.2°C. Scanning electron microscopy was used to analyze MH dispersion within the matrix, correlating it with the macroscopic properties. This study offers an effective approach for selecting MH modifiers and developing high‐performance flame‐retardant and cold‐resistant materials.

ABSTRACT This study investigates the influence of freeze thaw cycles and collagen incorporation on the intrinsic properties of polyvinyl alcohol (PVA) and polyethylene glycol (PEG) scaffolds. The scaffolds were fabricated using varying freeze thaw cycles (0, 2, 4, and 6) and collagen was added to enhance the biocompatibility. The variation in freeze thaw cycles significantly impacted the porosity of the scaffold which in turn affects the rate of degradation, rheology and its mechanical property. Notably, with increase in number of cycles the compressive modulus of PVA/PEG/Collagen scaffold increased from 17.74 ± 5.02 MPa (cycle 0) to 25 ± 5.14 MPa (cycle 6). Rheological study indicated that cycle 6 has highest viscosity and elasticity which indicates the enhanced interaction of molecules of PVA and strong hydrogen bonding as the number of cycles increases. Porosity and swelling studies demonstrated that scaffolds from cycle 4 retained optimal water content and structural integrity leading to improved shape recovery. Collagen incorporation enhanced cell viability maintaining values above 70% up to cycle 4. These findings suggest that PVA/PEG scaffolds with collagen, particularly at cycle 4 offered promising mechanical and biological characterizations suitable for tissue engineering applications.

ABSTRACT This study presents the development of thermoplastic polyurethane (TPU) and silica aerogel powder (SAP)‐based composite coatings for enhancing the thermal insulation performance of cotton fabrics. A solvent pre‐filling and replacement method using N, N‐dimethylformamide (DMF) was employed to preserve the aerogel's porous structure during processing. By systematically varying TPU concentration (15%–25%), TPU/SAP ratio, and coating thickness (35–55 μm), the effects on thermal conductivity, mechanical durability, water repellency, and comfort were investigated. Results showed that DMF pre‐filling effectively prevented TPU infiltration into aerogel pores, improving insulation efficiency. Optimal performance was achieved at 20% TPU, a 7:3 TPU/SAP ratio, and a 55 μm thickness, yielding a low thermal conductivity of 0.1043 W m −1 K −1 , a water contact angle of 112°, and an air permeability of 7.68 mm/s. After five washing cycles, the fabric retained good insulation properties with only a 3.3% increase in thermal conductivity and a 13.2% reduction in peel strength. These findings demonstrate the feasibility of TPU/SAP/DMF coatings for durable, breathable, and thermally insulating textile applications.

ABSTRACT To address environmental concerns of conventional flame retardants, MgAl‐layered double hydroxide (LDH) was synthesized from hydro‐magnesite. Utilizing hydrotalcite's structural memory effect, Cu was incorporated into LDH through acid activation and reconstruction. The obtained LDH was combined with ammonium polyphosphate (APP) into polyvinyl chloride (PVC). Composite thermal stability and flame retardancy were systematically evaluated. Results demonstrated that MgAlCu‐LDH/APP/PVC exhibited optimal performance, with limiting oxygen index (LOI) increasing from 26.1% (pure PVC) to 31.4%, achieving UL‐94 V‐0 rating. Cone calorimetry tests showed 19.7% and 20.9% reductions in peak heat release rate (PHRR) and total heat release (THR), respectively. Peak smoke production rate (PSPR) and total smoke production (TSP) decreased by 27.8% and 48.9%. These enhancements originated from synergistic dilution of flammable gases by NH 3 (from APP decomposition) and CO 2 (from LDH). Additionally, APP's acidic sites and Cu's catalytic effect jointly promoted PVC dehydrochlorination and aromatization, forming a dense char layer that effectively suppressed heat and mass transfer. This acid activation–in situ replacement method provides a novel strategy for synthesizing MgAlCu‐LDH and other ternary LDHs, demonstrating promising potential for improving polymer fire safety.

ABSTRACT Owing to its high lithium‐ion conductivity, the cubic garnet‐phase material Li 7 La 3 Zr 2 O 12 (LLZO) is a widely adopted key component in the fabrication of composite solid‐state electrolytes (CSSEs). Nevertheless, the advancement of all‐solid‐state lithium batteries (ASSLBs) is still hindered by two major challenges: the high intrinsic crystallinity of poly(ethylene oxide) (PEO) and poor interfacial stability. Herein, cubic garnet Li 6.3 La 2.7 Ba 0.3 ZrNbO 12 (LLBZNO) featuring Ba and Nb co‐doping was first prepared by a conventional solid‐state method. Following this, the material was dispersed within a PEO matrix to construct composite solid‐state electrolytes. Adding LLBZNO served to decrease PEO's crystallinity while enhancing its mechanical flexibility and bolstering its interfacial compatibility with lithium metal. The optimized membrane demonstrated superior properties, including a high Li + transference number of 0.75 (at 60°C) and an extended electrochemical stability window of up to 5.1 V (vs. Li/Li + ) under the present testing conditions. It also showed an excellent ability to suppress dendrites, facilitating stable cycling at 0.1 mA cm −2 for 1500 h without short‐circuiting. Furthermore, the LFP/LLBZNO–PEO/Li battery delivered a high discharge capacity of 101.6 mA h g −1 after 300 cycles at 1°C with nearly 99% coulombic efficiency. These findings highlight that LLBZNO‐PEO composite solid electrolytes possess superior ionic transport, electrochemical stability, and mechanical robustness, providing a viable pathway toward the advancement of next‐generation high‐performance ASSLBs.