Macromolecular Materials and Engineering最新文献

The utilization of hemicellulose in fiber production offers a sustainable route for textiles by transforming an otherwise wasted component of wood biomass into value-added material. The high hemicellulose content in these fibers poses challenges for alkaline wet processing, particularly during dyeing with reactive dyes. This study provides a systematic evaluation of how different alkaline conditions influence both the structural stability and dyeability of hemicellulose-rich (HR-Cell) fibers, addressing a knowledge gap in the processing of next-generation biobased cellulosic fibers. We investigate the dyeability and structural stability of HR-Cell fibers under sodium hydroxide (NaOH, 5–10 g/L) and sodium carbonate (Na₂CO₃, 5–20 g/L) treatments. Comprehensive characterization of HR-Cell fibers, including carbohydrate analysis, molar mass distribution, intrinsic viscosity, degree of polymerization, and crystallinity, showed that NaOH at 10 g/L led to hemicellulose degradation and cellulose depolymerization, whereas Na₂CO₃ preserved hemicellulose even at elevated concentrations. Dyeing experiments using C.I. Reactive Red 141 and C.I. Reactive Yellow 6 revealed that HR-Cell fibers consistently exhibited higher dye exhaustion, fixation, and color strength compared to cotton, viscose, and Lyocell fibers. The most favorable dyeing results were achieved with 15 g/L Na₂CO₃, which offered optimal conditions for activating fiber hydroxy groups, minimizing dye hydrolysis, and preserving hemicellulose in the fibers. Colorfastness tests confirmed very good to excellent resistance to washing, rubbing, and light across all samples and conditions.

An one-step procedure of simultaneous electrospraying and electrospinning is employed to produce fiber mats of a poly(vinylidene fluoride) (PVDF)/thermoplastic polyurethane (TPU) blend and polylactide (PLA) coated with singlewalled carbon nanotubes (SWCNTs). Thermoelectric investigation of the mats yielded Seebeck coefficients of 21–27 µV·K⁻¹ that are almost independent of the SWCNT content and the polymer type. Control measurements using SWCNT buckypapers reveals that the thermoelectric properties of the SWCNTs is mostly determined by n-type doping effect of the solvents and additives used for electrospraying; the polymer nanofibers act mostly as porous mechanical support. Gas sensing experiments using PVDF/TPU and PLA-based electrospun mats containing 0.25 wt% SWCNTs exposed to saturated acetone vapor demonstrate a significant sensor response (change in resistance) for both polymers. Sensor recovery is more effective in the PLA-based mats compared to the PVDF-based one. In cyclic tests with short exposure times, both mats show highly stable and reproducible sensing behavior. The sensing mechanism is primarily driven by interactions between the solvent molecules and the SWCNTs (charge transfer) rather than by interactions with the polymer matrix (e.g., polymer swelling).

Soft polyurethane fouling-release coatings are modified with synthesized mPEG-305, a hydrophilic PEG-based additive, and a commercially hydrophobic PDMS-based additive by click chemistry to generate hydrophilic and hydrophobic surface domains. Sessile drop contact angle measurements reveal polarity gradients ranging from ∆Ө = –32° to ∆Ө = 120°. AFM and SEM demonstrate successful additive incorporation (hydrophilic and hydrophobic additive addition of 2.5–20 mol% and 5–15 mol%) and the formation of two-phase systems with microstructures, including spherical hydrophobic and characteristic “wrinkled” morphologies. Captive bubble contact angle measurements of systems with “wrinkled” microstructures indicate dynamically hydrophilic behavior, with contact angle changes of up to 15° over 33 days of immersion in demineralized water. Static immersion tests in the North Sea (Helgoland) for 18 weeks demonstrate enhanced bio-repulsivity, with LoF values decreasing from 4 to 2–3 for systems with the strongest polarity gradient (∆Ө = 112°–120°), additive contents of 5–10 mol%, dominant wrinkled microstructures with pronounced stiffness (5 mPa) and topographical (100 nm) gradients, and dynamically hydrophilic contact angles changes of 15°. This highlights the critical influence of polarity gradients, microstructural heterogeneity and dynamic hydrophile behavior on the bio-repulsivity of polyurethane coatings.

Christopher Krüsener and Ulrich A. Handge^*

Macromol. Mater. Eng. 2025, 310, 2500128

https://doi.org/10.1002/mame.202500128

This model correlates the neck radius y and the time-dependent particle radius r with the surface tension Γ, the time t, and the zero shear-rate viscosity η₀ and the initial particle radius r₀ = r(t = 0).

This correction does not affect the results and the conclusions presented in the paper. The authors apologize for the inconvenience caused.

With the growing demand for advanced biophysical signal monitoring systems, the development of stretchable, adaptable, and functional flexible materials has become essential. Flexible sensors capable of detecting facial expressions, voice signals, and environmental stimuli show great potential in personalized healthcare, human–machine interfaces, and wearable electronics. Despite advancements, current flexible sensors face limitations such as low sensitivity to micro-strains, insufficient anisotropy, and poor environmental adaptability, restricting their broader application. This study introduces a high-performance stretchable sensor composed of carbon nanotube (CNT) and silver (Ag)-based conductive inks integrated with a monodomain liquid crystal elastomer (LCE) substrate (Ag/CNT/LCE). The LCE substrate offers sensitive mir-costrains detection intrinsic anisotropy, and thermal-response capability. The conductive ink combines the mechanical robustness of CNTs with the excellent conductivity of Ag, suppressing CNT aggregation and improving electrical stability under strain. The Ag/CNT/LCE sensor exhibits a gauge factor of 3.93, rapid response times (120 ms), and exceptional cyclic durability over 2500 cycles. Additionally, its thermoresponsive behavior enhances adaptability to environmental changes. Demonstrated applications include facial emotion recognition, voice monitoring, and deformation-based environmental sensing. By integrating multifunctionality, structural durability, and dynamic adaptability, the Ag/CNT/LCE sensor serves as a promising platform for wearable electronics, and next-generation healthcare technologies.

To address the global crisis of 6.3 billion tons of non-degradable plastic waste, polysaccharides (starch, chitosan, cellulose, etc.) have emerged as sustainable alternatives for food packaging. This review systematically analyzes five representative polysaccharides, highlighting their structural engineering strategies (e.g., nanocellulose reinforcement) and functional modifications (e.g., anthocyanin-based pH responsiveness). We propose a comprehensive framework integrating cost, performance, and policy factors to benchmark industrialization challenges of key polysaccharides, with starch-nanocellulose composites identified as the most scalable candidate. Integrated intelligent-active packaging systems (e.g., pH-sensitive films with real-time monitoring) demonstrate synergistic potential to extend food shelf life by 30%–50% while aligning with global policies (EU SUP Directive, China's 14th Five-Year Plan). Despite challenges in thermal stability (e.g., starch degrades at 100°C–180°C) and scalability, policy-technology synergies are critical to accelerate commercialization.

Efficient recycling of mixed plastic waste remains challenging due to the intrinsic immiscibility of constituent polymers, which compromises mechanical performance. Here, a synergistic compatibilization strategy combining reactive maleic anhydride–grafted low-density polyethylene (LDPE-g-MA) and non-reactive styrene–ethylene–butadiene–styrene (SEBS) is demonstrated to enhance interfacial adhesion and mechanical properties of LDPE/PS/PA6 blends. The cooperative action of LDPE-g-MA and SEBS minimized mutual interference and improved compatibilization efficiency at both LDPE/PA6 and LDPE/PS interfaces. In the LDPE/PS/PA6 (40/30/30) blend, the bicontinuous LDPE/PS morphology with PA6 encapsulated in PS transformed into an LDPE matrix containing salami-like core–shell domains with mixed PS/PA6 cores upon addition of 5 wt.% LDPE-g-MA and 5 wt.% SEBS. In the LDPE/PS/PA6 (70/15/15) blend, the PA6@PS domains evolved into distinct, refined salami-like structures with inner PS cores and interfacial localized PA6 domains upon addition of 3 wt.% LDPE-g-MA and 3 wt.% SEBS, increasing notched impact strength from 3.3 to 18.2 kJ·m⁻². In the LDPE/PS/PA6 (15/15/70) blend, LDPE@PS core–shell domains converted to salami-like PS@LDPE structures with 3 wt.% LDPE-g-MA and 4.5 wt.% SEBS, enhancing impact strength from 2.9 to 11.7 kJ·m⁻². This work offers an effective, industrially relevant route to tailor morphology and upgrade the performance of heterogeneous plastic waste toward sustainable recycling.

Polymer chains capable of forming metal complexes have been widely utilized in biomedical applications. The formation of polymer metal complexes offers size-related advantage, and the locally concentrated state of metal complexes increase inherent catalytic activity and molecular interaction. The specific polymer architectures provide additional benefits to form supramolecular assemblies to enhance their properties. More details can be found in the Perspective by Tiancheng Wang and Shigehito Osawa (DOI: 10.1002/mame.202500319)

Hydrogen bonding plays a pivotal yet often overlooked role in shaping the structure and dynamics of alginate-based materials. In this study, we use molecular dynamics (MD) simulations to investigate how hydration and solvent environment influence the organization of neutral alginate at the molecular and mesoscale levels. Starting from short isolated chains and progressing toward periodic and entangled systems, we systematically vary water content and examine structural responses using radial and minimal distance distribution functions, as well as geometric analysis based on Alpha Shapes. We find that hydration transforms the polymer matrix from compact, rigid bundles into layered and porous nanostructures, with water acting not merely as a plasticizer but as an active mediator of hydrogen bonding. Even small amounts of water accelerate supramolecular aggregation and promote internal flexibility. At higher hydration, polymer–polymer contacts become more diffuse yet remain structurally coherent. A comparison with ethanol reveals solvent-specific effects on porosity and tortuosity, while the functional surface composition remains robust across all conditions, closely reflecting the molecular stoichiometry of the polymer. These results provide a detailed molecular-level understanding of solvent-mediated self-assembly in alginate and offer general design principles for soft, bioinspired materials where hydrogen bonding is the key structural motif.