ABSTRACT This study prepared PI/PTFE (polyimide/polyfluoroethylene) bilayer composite films. Firstly, the inert surface of the PI film was modified using chemical wet acid etching. Subsequently, PTFE latex and FEP latex were blended and applied onto the modified PI film through a coating–drying–sintering process to form the bilayer composite film. The film formation and modification mechanism were investigated, and comprehensive analysis was conducted on the surface morphology, thermal properties, crystallinity properties, and mechanical properties of the composite film samples. Contact angle measurements and SEM results demonstrated that acid‐etched wet treatment effectively enhanced the surface roughness of the PI film, improving latex film formation. FT‐IR confirmed the chemical structural stability of the blended PTFE/FEP (fluorinated ethylene propylene) alloy coating after thermal treatment. Cross‐sectional SEM and mechanical testing revealed reliable adhesion between the blended coating and the modified PI substrate. DSC and GI‐XRD studies elucidated FEP's influence on coating crystallinity. Subsequent in situ POM analysis revealed that FEP, acting as a filler, improved PTFE flowability and reduced stress relaxation, transforming the coating surface from convex to concave. This topographical change was confirmed by SEM characterization and further validated by peel test results.

ABSTRACT Urea–formaldehyde (UF) resin is the most widely used adhesive in the wood‐processing industry due to its low cost, excellent bonding performance, and nearly colorless glue line. However, UF resins and UF‐bonded products release formaldehyde, a harmful pollutant that poses risks to indoor air quality and human health. Substantially reducing these emissions without compromising bonding performance remains a major challenge. This study develops a low‐formaldehyde‐emission UF resin (formaldehyde‐to‐urea molar ratio = 0.98) through a combined approach of 4 wt.% ammonia modification and 4 wt.% melamine copolymerization, achieving a formaldehyde emission of only 0.23 mg/L. Structural analysis reveals that the addition of ammonia consumes formaldehyde, which reduces the hydroxymethyl group content, branching density, and curing rate, while increasing the residual urea content. As a result, plywood bonded with the ammonia‐modified UF resin exhibits lower formaldehyde emissions but compromises water resistance. Subsequent melamine copolymerization effectively enhances water resistance and further reduces the formaldehyde emission from 0.26 to 0.23 mg/L. This synergistic strategy provides an effective solution for significantly lowering formaldehyde emissions while maintaining acceptable bonding performance that meets the requirements of Chinese Standard GB/T 9846‐2015, demonstrating strong potential for industrial application.

ABSTRACT The development of polymer composites remains largely dependent on trial‐and‐error experimentation, despite increasingly complex performance requirements in industrial applications. An interpretable machine‐learning framework is presented for the simultaneous prediction of nine mechanical, thermal, electrical, and physicochemical properties of polymer composites using an industry‐derived dataset comprising 112 commercial products. Unlike most prior studies that focus on a single property or limited material systems, the proposed approach models multiple properties across a broad range of commercially relevant polymers, fillers, and additives. Multiple feature set configurations are systematically evaluated within an ensemble learning framework incorporating Shapley Additive exPlanations (SHAP)‐based feature selection and interpretation, demonstrating that composition‐based feature generation capturing nonlinear interactions yields the most robust predictive performance. The resulting models achieve external test set coefficients of determination ( R 2 ) exceeding 0.90 across all properties. SHAP‐based interpretation confirms physical consistency with established composite mechanisms, while composition–property contour analyses provide practical guidance for identifying formulation trade‐offs among competing properties. The models are implemented in the PolyMIDAS platform, enabling composition‐based property prediction and multi‐property pre‐screening prior to experimental compounding. Overall, this work establishes a practical and interpretable AI‐driven framework that supports rational polymer composite design and reduces reliance on costly iterative experimentation.

ABSTRACT Vinyl ester resin (VER) is highly flammable, which limits its use in applications requiring high flame resistance. However, conventional flame‐retardant approaches often degrade its mechanical properties. To improve both the flame retardancy and mechanical performance, this work developed a grafting strategy incorporating phosphorus‐containing flexible side chains. Three DOPO‐based diol derivatives with different chain lengths (DOPE, DOPB, and DOPH) were synthesized and then grafted onto the VER backbone through 4,4′‐methylenediphenyl diisocyanate (MDI) to obtain VER/M‐DOPx systems. The modified resins showed obvious improvements in both flame retardancy and mechanical properties. VER/M‐DOPE and VER/M‐DOPB achieved UL‐94V‐0 ratings, with LOI values of 28.6% and 26.7%, respectively, while VER/M‐DOPH reached a V‐1 rating and an LOI of 28.9%. VER/M‐DOPB showed the best flame‐retardant effect, reducing the peak heat release rate (PHRR) and total heat release (THR) by 68.5% and 43.7% compared with VER. The incorporation of flexible DOPO‐based diol chains also enhanced toughness and strength; VER/M‐DOPE exhibited increases of 4.53%, 26.24%, and 81.35% in tensile, flexural, and impact strengths, respectively. These results indicate the feasibility of enhancing both the flame retardancy and the mechanical properties of VER through grafting phosphorus‐containing flexible side chains.

ABSTRACT Poly(ethylene succinate) (PES), as a biodegradable aliphatic polyester, has excellent biodegradability, good flexibility, and ductility. However, its poor crystallization behavior limits its large‐scale practical applications. In this work, dimethyl oxalate (DMO) was introduced as a third monomer into the polymerization system of succinic anhydride (SAA) and ethylene glycol (EG). While preserving the main chain integrity of PES, a series of PESO X copolymers were synthesized via copolymerization to enhance the crystallization ability of PES. The incorporation of DMO not only significantly improved the crystallization properties of the copolymers but also enhanced their mechanical performance and thermal stability. When the DMO content was 15%, the crystallization temperature of the copolymer increased from 44.0°C to 60.7°C. The yield strength improved from 19.20 ± 0.86 MPa to 25.29 ± 0.79 MPa, and the elongation at break increased from 13.60% ± 0.86% to 28.01% ± 0.69%. The PESO X copolymers synthesized by this method have excellent crystallization and mechanical properties, which improve the production and processing efficiency of PES, reduce industrial energy consumption, and improve economic efficiency.

ABSTRACT Due to the low notched impact strength, poly(trimethylene terephthalate) (PTT) with excellent toughness and good thermal properties have been attracted more attention. This study synthesized Poly(trimethylene terephthalate/isophthalate/carbonate) (PTTIC) copolymer with excellent notch impact strength from the green dimethyl carbonate (DMC) as the comonomer. The PTTIC copolymers with various DMC contents were synthesized via a two‐step melt polycondensation method. Their structure, thermal properties, crystallization behavior, mechanical properties, and rheological properties were systematically investigated. Mechanical property tests indicated that the introduction of DMC achieved the transformation of the material from “strong and brittle” to “resilient and durable”. PTTIC 30% achieved the optimization of toughness and its elongation at break and notched impact strength were greatly enhanced compared with pure PTTI. Rheological and dynamic mechanical analysis (DMA) showed that PTTIC 30% exhibited a unique viscoelastic balance behavior in the melt state, corresponding to its optimized impact resistance. This study verified the feasibility of copolymerization modification of PTTI using the green monomer DMC, and the introduction of DMC effectively improves the comprehensive toughness of the material. This work provides a valuable material basis and theoretical support for its application in high‐value‐added fields such as engineering plastics.

ABSTRACT With the advancement of functional textiles, polyacrylonitrile (PAN) is widely used in cold‐proof fabrics for its excellent thermal insulation but suffers from inherent hydrophobicity causing stuffiness during wear. Sodium alginate (SA), a natural polysaccharide rich in hydrophilic groups (‐OH, ‐COO − ), boasts outstanding moisture absorption and biocompatibility. This study developed SA/PAN composite films as a basis for functional fibers, preparing eight samples by adjusting SA concentration (0%, 1%, 2%), coagulation time (30 and 60 s), calcium chloride (CaCl 2 ) addition, and drying method (freeze‐drying/room‐temperature drying). Comprehensive characterizations (SEM, FT‐IR, porosity, etc.) revealed SA and PAN form composites via physical blending and Ca 2+ cross‐linking. Freeze‐drying is key for aerogel‐like porous networks, with sample 2601 (2% SA, freeze‐dried, no CaCl 2 ) achieving ~75% porosity. Sample 2610 (2% SA, room temperature dried, with CaCl 2 ) showed optimal hygrothermal performance (14.7% moisture regain, 133.79 J/g integral heat). High SA concentration constructs a porous skeleton, CaCl 2 enhances hydrophilicity through “hydrogen bonding + ion‐dipole” synergy, and freeze‐drying prevents pore collapse. This work elucidates the process control principles of the SA/PAN composite system, providing vital data and theoretical support for optimizing the wet‐spinning process of moisture‐absorbing and heat‐generating fibers.

ABSTRACT The tire antioxidant, N ‐(1,3‐dimethylbutyl)‐ N ′‐phenyl‐ p ‐phenylenediamine (6‐PPD), poses a severe environmental threat due to its conversion to 6‐PPD‐quinone, a compound highly toxic to aquatic life. Propyl gallate and lignin are bio‐derived compounds advocated as alternatives for 6‐PPD. This study presents a comprehensive side‐by‐side evaluation of propyl gallate and lignin against 6‐PPD, assessing their material performance and leaching potential. Rheological and mechanical testing reveal significant trade‐offs: while propyl gallate offered superior processing safety by increasing scorch time by over 40%, it drastically altered the vulcanizate's properties, reducing tensile strength by 20% and modulus by 46% while increasing elongation by 35%. Lignin's performance is closer to 6‐PPD, maintaining mechanical properties but increasing compound viscosity. Crucially, leaching studies quantified via LC–MS reveal that propyl gallate migrated substantially from the rubber, with 4.1 ppm detected in water after 216 h. Under the same conditions, leaching of the 6‐PPD is negligible, though its environmental transformation pathway differs. Lignin leaching is confirmed, but its complex polymeric nature prevented quantification, a key analytical challenge. The results demonstrate that replacing 6‐PPD is fraught with compromise; no drop‐in alternative currently satisfies the dual mandate of technical performance and environmental safety, underpinning the need for further innovation and ecotoxicological assessment of new compounds.

ABSTRACT Lab‐on‐a‐chip (LOC) devices allow for the manipulation of chemical synthesis and biological processes at small scales. Microfluidic devices are still limited in their flexibility; by employing two‐photon Direct Laser Writing (DLW) limitations in the fabrication of reconfigurable microfluidic devices can be overcome. In a post‐modification process of assembled microfluidic channels, a Christmas‐tree‐shaped microfluidic gradient generator (MGG) is equipped with dynamic trapping chambers based on thermoresponsive poly(N‐isopropylacrylamide) (pNIPAM) soft microactuators. In this study, we show an integrated microfluidic platform that combines dynamic pNIPAM microactuation with on‐chip functionalization, fluorescent labeling, and controlled release of amine‐functionalized polystyrene beads. The novelty of this work resides in the successful combination of all these functions on a single microfluidic device, which is highly relevant for the field of reconfigurable microfluidics. This dynamic approach enables us to trap beads at room temperature inside the equipped chambers and perform fluorescent labeling and washing steps on chip, before the beads are released at 45°C, without altering the flow conditions. The method offers great flexibility and a high degree of freedom in the fabrication of dynamic microfluidic devices, with excellent adaptability to experimental conditions and on‐demand labeling in real time.