Fibers and Polymers最新文献

Nanofibrillation is a sustainable physical method for producing ultrafine fibroin nanofiber (FNF) films with remarkable ultimate tensile strength and great thermal stability. However, the brittleness and poor flexibility of these films limit their possible applications. Herein, two hydrophilic plasticizers, including glycerol (Glyc) and propylene glycol (PG), were used to improve FNF flexibility. Fibroin nanofibers were blended with glycerol or propylene glycol at concentrations of approximately 23% and 50% w/w (based on the FNF weight), and their individual effects on the chemical, structural, mechanical, and thermal properties of the obtained FNF films were evaluated. Glycerol exhibited a stronger plasticizing effect than propylene glycol. As the concentration of glycerol increased, the flexibility of FNF increased proportionally, although water solubility also increased. In contrast, no plasticization was observed at low PG concentrations, whereas at higher concentrations, a minimal plasticization effect was observed. Moreover, PG-plasticized films exhibited higher water absorption capacity and maintained good stability in water. Both glycerol and propylene glycol exhibited antibacterial activity against Escherichia coli under the tested acidic conditions, with inhibition zones of around 7 and 9 mm, respectively. Unexpectedly, only films of plasticized propylene glycol composites exhibited minimal antibacterial activity, likely due to reduced concentration or entrapment within the polymer matrix. These findings provide new insights into using hydrophilic plasticizers to tune the structure–property relationships of fibroin nanofibers and highlight their potential as flexible, sustainable biomaterials for biomedical applications.

Graphical Abstract

Illustration of the impact of glycerol and propylene glycol on the secondary structure of nanofibrillated fibroin nanofibers (FNFs)

Mixed ultra-high molecular weight polyethylene and high-density polyethylene (C-PE) was blended with rutile titanium dioxide (TiO₂) nanorods modified with the silane coupling agent and spun into C-PE/TiO₂ blended fibers with improved aging resistance through melt spinning. Although polyethylene (PE) fibers are widely used outdoors, they suffer from aging when exposed to prolonged environmental conditions, which limits their outdoor applications. In this work, the effects of the modified rutile TiO₂ nanorod content on the morphology, mechanical properties, aging resistance, UV protection performance, and heat resistance of the prepared C-PE/TiO₂ blended fibers were investigated. The results indicated that the blended fibers containing 3 wt% rutile TiO₂ nanorods achieved good comprehensive performance. After 60 days of outdoor exposure under various conditions during summer, the C-PE/TiO₂ blended fibers showed high strength retention rates of 88.0% in seawater, 94.5% in distilled water, and 93.9% under natural sunlight. Furthermore, after 288 h of UV light aging, the strength retention remained at 93.7%. The strength retention rates of the C-PE/TiO₂ blended fibers were significantly higher than those of the C-PE fibers. The blended fibers also exhibited an ultraviolet protection factor (UPF) of 533.49. Thermal analysis revealed that the fibers exhibited an increased heat deformation temperature, from 85.75 to 98.46 °C. This study demonstrated that incorporating modified rutile TiO₂ nanorods into PE effectively produced fibers with enhanced aging resistance and UV protection for outdoor applications.

Auxetic metamaterials, characterized by a negative or zero Poisson's ratio (NPR), exhibit unique deformation properties leading to enhanced toughness, elasticity, shear resistance, and acoustic performance. These materials have significant applications in energy absorption, vibration damping, and shock absorption. This research focuses on designing and characterizing 3D-woven auxetic fabrics using Kevlar and polyester core-spun spandex yarns, with practical implications. Here, four different auxetic fabric samples were developed by varying the float length of the binder yarn. The results show that as float length increases, the fabric's thickness, areal density, and thread density initially increase due to the elastic yarn in the weft and then decrease due to fewer interlacement points. The in-plane auxeticity, shear resistance, and tensile properties follow a similar trend, initially increasing and decreasing with float length. Auxetic fabrics demonstrated superior peak loads and energy absorption in various tests. This research highlights the importance of optimizing float length to achieve desired auxetic properties, intending to develop 3D auxetic fabrics for advanced energy absorption applications. These findings contribute to the broader understanding and potential of auxetic materials in various engineering and biomedical fields, offering practical solutions for energy absorption challenges.

The traditional fluorine-containing finishing agents used for anti-fouling textiles not only cause serious environmental and health hazards, but also have the problem of insufficient fabric durability. Therefore, bio-based slippery finishing agents have great application prospects for textile finishing. In this paper, cellulose nanocrystal was thiol-modified with 3-mercaptopropyltriethoxysilane and then compounded with bisphenol A diglycidyl ether and amino-terminated double-end-capped polydimethylsiloxane. The cotton fabric surface was modified via a padding–drying–curing process. The amino-terminated double-end-capped polydimethylsiloxane endowed the coating with low-surface energy, which synergized with the dense micro/nanoscale rough structure formed by the modified cellulose to achieve slippery and anti-fouling functionalities. The surface morphology, chemical structure, and elemental distribution of the fabric were characterized, and its sliding performance, anti-fouling property, and water/oil repellency were tested. The results demonstrated that the cotton fabric modified with the bio-based fluorine-free slippery coating exhibited a sliding angle < 10°, enabling facile liquid movement and removal while possessing excellent water and oil repellency and environmental compatibility.

Graphic Abstract

Cotton/polyurethane stretch fabrics can exhibit local shade contrast and grin-through because conventional polyurethane is weakly colored under reactive-dyeing conditions optimized for cotton. This study compared the reactive-dyeability of regular polyurethane (RPU) and amine-rich polyurethane (ARPU) using nine commercial dyes representing vinyl sulfone (VS), bis-monochlorotriazine (Bis-MCT), and VS+MCT chemistries, followed by model same-bath dyeing with cotton, time-dependent dyeing analysis, and validation using industrial cotton/polyurethane single-jersey fabrics. ARPU showed substantially higher and strongly dye-dependent color strength than RPU, with the greatest coloration obtained for the VS-type dyes. At 2.0%omf, the color strengths of ARPU dyed with VS-B19, VS-Bk5, and VS-B21 were approximately 28.3-, 37.1-, and 8.8-fold higher, respectively, than those of RPU, while cotton coloration remained broadly comparable between the cotton/RPU and cotton/ARPU systems. The RPU–ARPU difference became more pronounced after alkali addition, consistent with a contribution from the higher relative abundance of secondary-amine functionality in ARPU to interactions or reactions with activated reactive dyes. Enhanced ARPU coloration was not accompanied by systematic deterioration in washing, perspiration, rubbing, or light fastness. The levelness parameter increased from 3.82 ± 0.083 for cotton/RPU to 4.68 ± 0.104 for cotton/ARPU, and reduced grin-through was observed under 10% extension. These results indicate that amine-rich modification can improve polyurethane–cotton color compatibility while maintaining practical color-fastness performance.

The rapid development of smart wearable technology has driven innovation in the field of flexible strain sensors. Carbon nanotube (CNT) fibers have emerged as promising candidates for the fabrication of flexible strain sensors due to their exceptional flexibility, remarkably high specific surface area, outstanding mechanical properties, and excellent electrical conductivity. However, interstitial voids between CNT bundles constitute structural defects that impair both load-bearing capacity and electron transport efficiency. This limitation can be effectively mitigated by incorporating metal nanoparticles, which not only fill these voids but also enhance composite performance through their intrinsic low electrical resistance and exceptional chemical inertness. In this study, MXene was utilized as a reducing agent to directly reduce platinum particles from chloroplatinic acid and autonomously grow into the voids of carbon nanotube yarns without the need for additional reducing agents. This modification strategy resulted in substantial enhancements in both mechanical and electrical properties: The tensile strength of platinum-modified CNT yarns increased from 121.2 to 137.27 MPa (13.3% increase), while electrical conductivity demonstrated an 85.3% improvement from 6.18×10⁴ S/m to 11.45×10⁴ S/m. The prepared flexible and stretchable strain sensors exhibit a resistive change of 380%, a tensile strain range of 0–30%, a GF sensitivity of 23.8, a fast response time of 0.6 s, a recovery time of 0.8 s, and dynamic sensing stability under varying conditions. Significantly, the sensor enables multi-channel synchronous monitoring of biomechanical signals at major human joints, establishing a new design framework for CNT yarn-based elastic strain sensors.

Carbon fibre-reinforced polyetheretherketone (CF-PEEK) is a promising biomaterial due to its high strength, stiffness, radiolucency, and wear resistance; however, its bioinert nature limits osteointegration in orthopaedic applications. In this study, porous CF-PEEK scaffolds with controlled porosities (45–70%) were fabricated using compression moulding and the NaCl particle leaching technique. To enhance bioactivity, the scaffolds were surface-activated, and a microwave-assisted calcium phosphate (Ca-P) coating was applied in a biomimetic medium. Morphological evaluation using field emission scanning electron microscopy (SEM) revealed a uniform, interconnected porous architecture in uncoated scaffolds, while Ca-P-coated scaffolds exhibited a continuous apatite layer, which was confirmed by cross-sectional SEM micrographs. The X-ray diffraction analysis identified characteristic semi-crystalline PEEK peaks, along with additional Ca-P phases, after coating of the scaffolds. All coatings demonstrated strong adhesion to the scaffolds, as indicated by the 5B ratings for P60C and P70C in the cross-cut adhesion test. The measured porosity closely matched the initial porogen content. Water absorption increased with porosity, reaching 69.02% for the scaffold with the highest porosity (P70). Mechanical testing showed a compressive strength of ≈ 132.48 MPa for P70, which is suitable for load-bearing orthopaedic implants. Biological assessments demonstrated enhanced protein adsorption, haemocompatibility (haemolysis < 5%), and optimal in vitro bioactivity in Ca-P-coated scaffolds. Cell culture studies with MG-63 osteoblast-like cells demonstrated superior cell viability and adhesion, particularly with the highly porous P70C scaffold. Therefore, the developed Ca-P-coated CF-PEEK scaffold exhibited an optimal balance of mechanical integrity, bioactivity, and cytocompatibility, making it a strong candidate for orthopaedic applications.

This study utilized the traditional medicinal plant apocynum venetum leaf as raw material to extract apocynum venetum leaf polysaccharide (ALP) via hot water extraction combined with an ethanol/ammonium sulfate aqueous two-phase system. Using ALP and polyvinyl alcohol (PVA) as raw materials, ALP/PVA composite nanofiber films were successfully prepared by electrospinning technology. Systematic characterizations indicated that ALP was effectively dispersed and stably integrated within the PVA matrix. Performance tests revealed that the composite film possesses excellent antioxidant activity (DPPH radical scavenging rate reaching 90.9% at 0.2% ALP addition), improved mechanical properties (optimal strength per unit thickness of 18.59 MPa at 0.1% ALP addition), as well as good hydrophilicity, preliminary qualitative antibacterial activity, and a proof-of-concept demonstration for short-term food preservation. This study provides a feasible strategy and theoretical basis for developing green active packaging materials based on natural polysaccharides.

Structurally colored yarns based on photonic crystals show great potential for textile applications; however, their practical use is limited by insufficient structural stability under mechanical stress. This work focuses on the fabrication and application of highly robust photonic crystal-based structurally colored yarns. Acrylic yarns served as flexible substrates, onto which SiO₂ colloidal microspheres were assembled to form structural color layers, followed by encapsulation using different curing systems to improve structural stability and mechanical performance. Five curing agents, polyvinyl alcohol (PVA), waterborne acrylic emulsion, 2-phenoxyethyl acrylate / Ethyl (2,4,6-trimethylbenzoyl) phenylphosphinate (PHEA/TPO-L), polyethylene oxide (PEO), and polydimethylsiloxane (PDMS) were comparatively studied in terms of color retention and mechanical properties. The result showed that PVA spraying and acrylic emulsion dipping effectively enhance interfacial adhesion while maintaining the ordered arrangement of microspheres, whereas PHEA/TPO-L, PEO, and PDMS treatments weaken the structural color to varying degrees. The rinsing, soaking, and rubbing tests demonstrated improved color durability after curing treatments. Additionally, the cured structurally colored yarns were successfully woven into plain fabrics with a semi-automatic sample loom, and the structural color remained intact during weaving, confirming their potential for textile processing. This study provides experimental support for improving the stability and textile processability of structurally colored yarns and establishes a basis for future standardized textile performance evaluation.

Wearable strain sensors have attracted extensive attention due to their wide applications in human motion monitoring, health monitoring and human–machine interface technology. However, wearable strain sensors have been suffering from some drawbacks, such as narrow working range, low sensitivity and unstable monitoring of underwater human movements, which significantly limited their practical applications. Herein, we developed a novel wearable strain sensor through constructing a stable CNT-bridged Ag NPs conductive network structure and PDMS hydrophobic layer on the surface of PU yarns. The PDMS/Ag/CNT/PU yarns showed intriguing integrated characteristics, including excellent mechanical properties (stress up to 13.54±0.66 MPa, strain up to 534% and toughness up to 37.53 ± 1.28 MJ m⁻³), high conductivity (0.3 Ω) and superior hydrophobic (134.9 ± 3.5). When served as a wearable strain sensor, the PDMS/Ag/CNT/PU yarn exhibited high gauge factor (GF) both in subtle and large strain ranges, stability and repeatability for monitoring the human movements. In terms of underwater sensing performance, the wearable strain sensors displayed high sensitivity, good long-term stability and environmental tolerance to different deformations such as water vibration, droplet shock and a series of underwater measurement. This work provided a valuable strategy to design the high-performance wearable strain sensors, which can work stable in the underwater environment.