Research articles

We report a custom ball-on-disc tribometer to quantitatively detect the onset of surface damage in polymer composites under continuous sliding contact. Conventional tribometers primarily monitor friction coefficients but often fail to the detect the precise surface damage initiation. In contrast, our system continuously monitors vibration signals and identifies surface damage as a sudden increase in vibration signals. Using this approach, we evaluate the effects of glass-fiber (GF) content and surface roughness on the damage onset time in GF-reinforced polyamide 66. The proposed methodology enables sensitive, robust early-stage spalling characterization.

Poly(vinyl alcohol) (PVA) side-chain was substituted with 5–7 mol% lignin-derived 2-pyrone-4,6-dicarboxylic acid (PDC) units. Even this low incorporation markedly improved thermal and mechanical properties, indicating strong effects on intermolecular interactions and chain packing. Acid–base titration showed higher acidity than poly(acrylic acid), demonstrating effective polyelectrolyte behavior. Composting tests confirmed biodegradability comparable to pristine PVA. These findings present a new strategy for introducing lignin-derived PDC into side-chain architectures and highlight its potential as a functional biomass-based polyelectrolyte material.

The mechanical properties of dual-crosslinked elastomers containing both dynamic and static crosslinks were systematically investigated. The contents of dynamic and static crosslinks were varied, and the resulting mechanical properties were examined. For tensile properties, static crosslinks contribute to structural integrity and stiffness at the expense of stretchability, whereas dynamic crosslinks increase stiffness and stretchability at the same time.

Microtubule-based active filaments driven by kinesin motors were studied using computer simulations to investigate how microtubule mechanics governs the filament behaviors under pinning and subsequent depinning at their leading ends. Stiff filaments maintained nearly straight conformations upon depinning, whereas flexible ones exhibited buckling and spiraling prior to depinning, revealing that the distinct behaviors were visible manifestations of microtubule mechanics. The underlying mechanisms were elucidated with a mechanistic scenario. These findings conversely suggest that microtubule mechanics can be inferred via active filament dynamics.

Unlike conventional color e-books, which employ three layers of CLC films to reflect red, green, and blue light to achieve a full-color reflective display. This study develops a novel dual-frequency bistable cholesteric liquid crystal (DFCLC) device. By integrating a transflective color filter and shifting Bragg reflection beyond the visible range, it supports both reflective and backlit color displays. This energy-saving design simplifies fabrication, improves sharpness, and requires zero continuous power, making it ideal for e-books and advertising.

Random copolymers of 4-phenylazophenyl methacrylate and phenethyl methacrylate in a typical ionic liquid, 1-ethyl-3-methylimidazolium trifluoromethylsulfonylimide, [C₂mim][TFSI] exhibit reversible, light-controlled LCST-type phase transitions. Photoisomerization of the azobenzene units shifts the cloud-point temperature, creating a bistable temperature window between 25 and 37 °C, where UV light induces dissolution and visible light restores phase separation. This simple molecular design enables non-volatile, light-switchable thermoresponsive polymer systems.

All-solid-rechargeable air batteries (SSABs) were developed using a redox active organic molecule (anthraquinone-2-carboxylic acid, AQC) in the negative electrode, proton conductive polymer (Nafion) membrane as solid electrolyte, and gas-diffusion oxygen electrode. The effects of Nafion membrane thickness (50 and 175 μm) and oxygen partial pressure in the cathode on charge/discharge characteristics, discharge rate performance, and cyclability of the resulting SSABs were investigated.

The supramolecular PE-A polymer-functionalized GO membrane system effectively enhances the structural characteristics and surface physical properties of GO nanosheets to achieve desirable nanofiltration performance.

Tetrakisarylamine-functionalized ethylenediamines (TAAs), used as an electron-transporting interlayer, modify the contact between the photoactive PCE14:BTP-4Cl layer and the ZnO-based cathode, thereby reducing interfacial trap states, facilitating charge transfer, and ultimately improving both power conversion efficiency and device stability.

Pyrene-functionalized poly(ethylene glycol) (PEG) was noncovalently grafted onto multiwalled carbon nanotubes (mwCNTs) via π–π stacking interactions, enabling stable aqueous dispersion with poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT: PSS) and fabrication of uniform conductive composite films. The films exhibited enhanced electrical conductivity, reduced mechanical shrinkage stress, and rapid electrothermal actuation, showing reversible bending deformation of flexible actuators under applied voltage (ON/OFF). Electrochemical characterization further demonstrated energy storage capability and interfacial charge transfer behavior, highlighting potential applications in low-voltage-driven flexible electrochemical actuators.

A facile filtration method was developed to fabricate Janus CNT@cellulose membrane, designed as an efficient photothermal material for solar-driven water vapor generation, with a focus on sustainability and low cost. The as-prepared membrane exhibited well performances in solar desalination and dye-containing wastewater treatment. The simple preparation method, self-floating ability, and high solar evaporation efficiency indicates that the Janus CNT@cellulose membrane demonstrates strong potential for practical applications.

An integrated extraction–NMR–SEC protocol is proposed for analyzing residual polymers (PHBV, PCL, and PBSu) after BOD biodegradation testing in seawater. ¹H NMR analysis assesses “NMR degradability,” which correlates strongly with BOD results, while SEC analysis identifies polymer chain scission through molecular mass changes. This practical and reliable approach enables a comprehensive understanding of biodegradation mechanisms in complex environments where direct analysis is challenging

Preparation of bis-imidazole-crosslinked polystyrene-based anion-exchange membranes involves simultaneous quaternization and crosslinking, with imidazolium cationic groups serving as both crosslinking nodes and anion-conducting sites, making these membranes suitable for fuel cell applications.

n-Type (AB)_n multiblock copolymers combining an NDI-based semiconducting polymer and polyisobutene segments were successfully synthesized to clarify how PIB length and content influence thermal, mechanical, and charge-transport properties. All copolymers were thermally stable (T_d^5% > 386 °C). The studied polymer films with 18–23 wt% PIB showed excellent crack resistance up to 100% strain. The OFET mobility based on the thin films decreased slightly (~13%) at 4–10 wt% PIB and remained the order of 10⁻³ cm²V⁻¹s⁻¹.

This study presents a heat- and UV-responsive disulfide-based covalent adaptable network (DS-CAN) as a repairable anticorrosion coating under mild conditions. UV irradiation at room temperature activates dynamic disulfide exchange, enabling localized network rearrangement, welding, and patching. The restored coatings recover structural integrity and corrosion resistance, offering an energy-efficient, on-demand, spatiotemporally controlled repair strategy for functional coatings.

Flexible polymer films were prepared by forming phosphoester-based dynamic covalent networks between poly(2-hydroxyethyl methacrylate) (poly(HEMA)) and 2-methoxy-2-oxo-1,3,2-dioxaphospholane (MP) via a heat-assisted solvent evaporation technique. The mechanical and thermal properties could be controlled by varying the poly(HEMA):MP ratio. At a certain amount of phosphoester units, the resulting films exhibited self-healing, reshaping, and degradability, offering a versatile approach to sustainable polymer development.

PEGylated lysozyme nanoparticles (PEG-LYZ NPs) with varying PEG contents were prepared to examine how PEG content affected nanoparticle formation, inhibition of Aβ₄₂ fibrillation, and nonspecific protein adsorption. Increasing PEG content promoted the formation of colloidally stable nanoparticles and enhanced the inhibition of Aβ₄₂ fibrillation. In addition, PEG-LYZ NPs exhibited size-selective binding to Aβ₄₂ while strongly suppressing the adsorption of unrelated larger proteins. These findings identified PEG content as a key design parameter for PEGylated protein nanoparticles for inhibiting Aβ fibrillation in biological media.

Hydrophilic polyethylene glycol (PEG) was grafted onto multiwalled carbon nanotubes (mwCNTs) via noncovalent bonding to improve water stability without damaging the nanotube morphology. Platinum (Pt) nanoparticles were subsequently deposited on the grafted nanotubes to fabricate a Pt-supported mwCNT, owing to the π–π interactions between the terminal pyrene moieties on the modified PEG chains and the CNT surface, the grafted material maintained stable dispersion. And the resulting material was developed as an electrode for a hydrogen electromotive force (EMF) sensor to investigate its hydrogen gas response behavior.

Isosorbide-based diamine and ether-linked dianhydrides are applied to derive a series of biobased poly(ether imides). Poly(ether imides) is expected to be stable to base development during photopatterning and lithography. Accordingly, the biobased poly(ether imides) show excellent thermal, mechanical, and dielectric properties. Moreover, photolithographic evaluations further confirm that the optimized biobased photosensitive polyimide system with a photobase generator enables stable negative-tone pattern formation with good pattern fidelity and thickness retention for micrometer-scale features.

A straightforward aqueous polymerization strategy was developed for preparing transparent CNF/PMMA composites on the basis of CNF-stabilized Pickering emulsions. By heat-molding composite powders, transparent CNF/PMMA plates with mm-scale thicknesses were prepared. The resulting composites exhibited high optical transparency, with total light transmittance > 80% at 600 nm.