Fibers and Polymers最新文献

Flax fibers contain naturally colored substances, which need to be removed by bleaching to produce excellent flax-based textiles in the subsequent process. However, the traditional bleaching process has the disadvantages of high temperature, large water consumption and high chemical oxygen demand (COD) value. Therefore, an appealing alternative to make flax fiber more sustainable is to design an environmentally friendly bleaching process, which has the advantages of low water usage, easy operation at ambient temperature and without addition of chemicals. In this paper, the influence of ozone bleaching on the optical property of flax fibers at different parameter conditions (reaction phase, ozone concentration, bleaching time, water pickup value, initial pH value) was investigated. The physicochemical properties of fiber samples after ozone bleaching were analyzed and compared with those of traditional bleached fibers. Results showed that the lightness and whiteness index of SFT-O₃-Gas-70% increased to 80.85 and 53.33, yellowness index decreased to 10.14 (ozone concentration 20%, 20 min, WPV 70%, pH 2.0), which was comparable with the SFT-TMB (80.75, 51.87 and 11.33). SEM analysis showed that the non-cellulosic components (hemicelluloses and lignin) on the fiber surface were removed after bleaching treatment. The crystallinity and thermal stability of samples after bleaching treatment increased due to the removal of non-cellulosic components. Compared with the SFT-TMB (16.07 cN/tex and 1166), the tenacity and degree of polymerization (DP) of SFT-O₃-Gas-70% decreased to 11.40 cN/tex and 779, respectively. The whole ozone bleaching process is under gas phase, normal temperature and pressure conditions, which greatly reduces water consumption and COD values of bleach wastewater. This study provides some guidance on the use of ozone for bleaching lignocellulosic fibers and the selection of cellulose protectants.

The substance principal used to synthesize these materials is fibroin, obtained from the silkworm’s cocoon (Bombyx mori) in the form of a filament, but can be converted into nanometric particles. After the synthesis, the obtained samples were characterized by size and Zeta potential (via nanosizer), X-Ray diffraction (XRD), specific area determination by the BET method, Infrared Spectroscopy with Fourier Transform with attenuated diffuse reflectance (FTIR), transmission electron microscopy (TEM). The silk fibroin nanoparticles (SFNp) were immobilized on polylactic acid (PLA)-knitted fabric and functionalized with chitosan for FTIR and XRD analyses, in addition to cytotoxicity analysis with colorimetric test (MTT) and cell adhesion. The DLS, FTIR and MET results confirm the formation of spherical silk fibroin nanoparticles with average sizes between 48 and 156nm, and zeta potential of − 19.95mV which characterizes a good dispersibility. Cell-viability assessment showed that SFNp is a non-cytotoxic material at low concentrations up to 48h, confirming that the nanoparticle synthesis method using the ternary system is an effective and low-cost alternative. This technique has great potential for use in the development of biomaterials, due to the production of knitted tissues with PLA functionalized with chitosan and immobilized with SFNp, exhibiting mechanical strength and biocompatibility.

The objective of this study is to develop cotton fabrics that are capable of reversible color change in response to temperature changes and of providing an opportunity for thermal management. To achieve this objective, chitosan/sodium alginate natural polymer-walled microcapsules with a thermochromic phase change system core, produced by the complex coacervation method were applied to cotton fabrics by impregnation and exhaustion processes. The thermochromic system contains crystal violet lactone (dye), phenolphthalein (developer), and 1-tetradecanol (solvent) and offers a temperature regulation function thanks to 1-tetradecanol which act as a phase change material. The second objective of this study is to examine the performance characteristics of the microcapsules when applied to cotton fabric via the impregnation and exhaustion method. The visual photographs and colorimetric measurement results indicated that the fabrics treated with microcapsules exhibited thermochromic properties with both application methods. The performance of fabric (Fabric 2) treated with microcapsules by the exhaustion method was superior in terms of color change compared to fabric (Fabric 1) treated by the impregnation method. However, the T-history results demonstrated that the thermoregulation effect of Fabric 1 and Fabric 2 was comparable. The results of the air and water permeability tests on the fabrics indicated that both microcapsule application methods resulted in the pores of the fabrics being filled, thereby significantly reducing the permeability values. In addition, the bending rigidity of the fabrics increased with the addition of microcapsules to the fabrics, while the tear strength decreased. As a result, microcapsules can be effectively applied to cotton fabric by both methods. Moreover, the exhaustion method provided superior performance in relation to the affinity effect of the polymers forming the capsule wall structure against cotton cellulose molecules.

Antibacterial composite membranes were fabricated in this study through the utilization of the electrospinning technique, with the intention of employing it as a skin mask. The membranes, comprising polycaprolactone and gelatin, were used to provide mechanical support with bioactivity for the membranes. Salicylic acid was used in combination with algae and zinc oxide nanoparticles as ingredients for these membranes. The physical and chemical characteristics of the membranes were assessed and it was revealed that the membranes exhibited nanofibrous structure. Zinc oxide nanoparticles, salicylic acid and the microalgae Phaeodactylum tricornutum were integrated into a nanofibrous structure for the first time. In addition, the biodegradation quantity, salicylic acid release and zinc ion release profiles of the membranes showed their potential as antibacterial membranes. Moreover, there was no observed growth of E. coli and S. aureus on the membranes’ surface during the antibacterial studies. Overall, the findings from the study demonstrated that these electrospun membranes possess potential as skin masks due to their antibacterial properties.

This study evaluates the effect of different compression angles on the compression performance of carbon fiber-reinforced plastic (CFRP) thin-walled tubes. It explores the potential improvement of performance by aluminum foam filling. CFRP tubes with different wall thicknesses (1 mm, 1.5 mm, and 2 mm) were used in the experiments. Quasi-static compression tests were conducted at 0°, 15°, 30°, and 45° compression angles to investigate the effects of compression angle changes on the mechanical response and energy absorption characteristics of CFRP tubes. The experimental results showed that the compression angle significantly affected the damage mode, energy absorption (EA), specific energy absorption (SEA), peak crushing force (PCF), and collision force efficiency (CFE) of CFRP tubes. Under axial compression (0°), CFRP tubes display their highest energy absorption capacity and stability. However, as the compression angle increases, particularly up to 45°, there is a notable decline in the EA, SEA, PCF, and CFE. This decrease correlates with a rise in buckling and shear damage modes, which are characteristics of oblique compression. In addition, aluminum foam filling significantly improved CFRP tubes’ energy absorption efficiency and crashworthiness. Aluminum-filled CFRP tubes exhibited higher EA and CFE than unfilled tubes at all tested compression angles, especially at 0° compression angle, where aluminum-filled CFRP tubes with a wall thickness of 1.5 mm achieved 81.6% CFE. This result highlights the significant role of aluminum-filled foams in improving the performance of CFRP tubes.

In this study, we explored the impact of electron beam (EB) radiation doses on Triallyl Isocyanurate (TAIC) grafting onto sheep wool fabric at room temperature and investigated the Thermo-mechanical properties. We varied the EB doses from 50 to 400 kilogray (kGy), with consistent critical parameters, such as TAIC monomer, methanol, and water solvent concentrations, during padding. We observed a steady increase in grafting yield correlating positively with the applied EB doses up to 150 kGy, beyond which the yield plateaued at around 12% despite higher EB doses. Scanning electron microscope (SEM) images of the irradiated samples showcased a uniform distribution of TAIC and its oligomers on the Wool Fiber surfaces. Through energy-dispersive X-ray (EDX) analysis, the presence of TAIC was confirmed by detecting C, N, and O elements. Attenuated total reflection fourier-transform infrared (ATR-FTIR) spectroscopy indicated chemical alterations in the hydrocarbons, thiol, amides, and disulfides of the EB-irradiated wool polymer, affirming the grafting and chain scission reactions. Thermal gravimetric analysis (TGA) demonstrated increased thermal stability of the EB-irradiated Wool Fibers to a higher temperature range. We noted changes in the mechanical properties of yarns and stiffness of wool fabrics correlated with the applied EB doses and grafting yield. However, the study determined that a 150 kGy EB dose was optimal for effective wool grafting with the given monomer and solvent concentrations.

In order to improve the infiltration and adhesion of epoxy resin to CFs and enhance the interfacial properties of CFs/EP composites, the water-soluble epoxy resin prepared by in-situ blending phosphorylation modification was compounded into a high-temperature-resistant carbon fiber sizing agent, and the CFs/EP composites were prepared by vacuum-assisted resin transfer forming method. The results showed that the prepared sizing agent contained epoxy resin, aliphatic ester, polyoxyethylene and other active oxygen-containing groups. It had good water solubility, small particle size, good stability, and could be dissolvable with water at room temperature in any proportion. The average particle size of 1% sizing agent emulsion was 17.7 nm, and it was stable at 4000 rpm for 30 min. The initial decomposition temperature of the sizing agent is 313 ℃, the mass residue rate is 65.60% at 400 ℃, and the mass residue is 20% at 600 ℃, which has excellent high-temperature resistance. The sizing agent can also significantly improve the surface energy of CFs, and increase its surface interface bonding and mechanical properties. When the content of sizing agent on the surface of CFs is 7.88 mg/g, the surface energy is 47.38 mN/m, and the breaking strength is 777.91 MPa, which is 24.42 and 29.29% higher than that of desizing CFs. The bend strength and shearing strength of the prepared CFs/EP composites are 107.38 MPa and 9.83 MPa, which are increased by 81.91 and 20.17% compared with the desizing products.

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Due to the poor interfacial adhesion of commercial basalt fibers (BFs), failure mechanisms such as fiber debonding, sliding, pull-out, and crack bridging occurred at BFs/polymer interfaces. In this work, BFs were surface modified by 3-aminopropyltrimethoxysilane (APTES) and succinic anhydride (SA) to improve their interface compatibility. The surface treatment was conducted after removing the original commercial sizing and pretreating them with high-temperatures and activation process. APTES and SA were successfully grafted on BFs rather than physical coating, it introduced specific functional groups, increased thermal stability and reduced surface defects of BFs. High-temperature reduced the –OH groups and weakened monofilament tensile strength, but activation process realized surface Si–OH regeneration, which enhanced thermal stability and tensile strength of BFs. The monofilament tensile strength of BFs followed a two-parameter Weibull distribution. The monofilament tensile strength of APTES- and SA-modified BFs increased by up to 84.3% compared with high-temperature reduced BFs. By modification, the functional groups were successfully introduced into commercial BFs, the maximum thermal decomposition temperature was 507 °C, increased by 35.7%. The modified BFs is expected to improve the overall performance of BFs/polymer composites.

Graphical Abstract

The microstructure, wettability, and electrochemical performance of MXene/polyacrylonitrile (PAN)-derived hybrid carbon nanofiber membranes (MCNFs) as high-performance supercapacitor electrode materials are reported. A series of MCNFs were prepared using electrospinning, carbonization, and vacuum-assisted filtration deposition methods. Carbonized PAN-derived carbon nanofiber membranes were used as substrates, and MXene dispersion was deposited onto both sides of the carbon nanofiber membranes (CNFs). Structural analysis showed that MXene nanosheets were uniformly attached to PAN-derived CNFs, with increasing deposition thickness on the surface as the MXene content in the dispersion increased. The addition of MXene nanosheets improved the hydrophilicity of CNFs, thus effectively promoting electrolyte penetration at the electrode/electrolyte interface. Thereby, the specific capacitance of PAN-derived pure CNFs increased from 60.2 Fg⁻¹ to a maximum of 436.5 Fg⁻¹ for the hybrid membrane MCNFs, showing a significant enhancement compared to CNFs alone, making it an efficient energy storage device.

Automotive seating fabrics, that come into direct contact with the human body, which have increased requirements for their tactile comfort properties, but it is still a great challenge to clear the relationship between structures and its performances. Hence, 44 knitting fabrics with the different structural parameters were prepared first, and then the properties such as tactile, bending and compressive performance were tested, and the intrinsic correlation between their performance indexes and the structural properties was analyzed. The results showed that the toughness of the fabrics varied greatly, and the main score was concentrated on 75 to 90. As for the bending stiffness, the warp bending hysteresis of fabrics was concentrated in the range of 0–0.15 gf·cm cm⁻¹, while that of the weft bending hysteresis was mainly concentrated in the range of 0–0.1 gf·cm cm⁻¹. Moreover, the compression behaviors of fabrics were 0.7 to 1.5 gf·cm cm⁻², 47.5 to 55% and 0.25 to 0.65, respectively. Tactile analysis of fabrics was carried out by establishing a comprehensive evaluation model, the average composite ratings of weft-plane fabrics, mesh fabrics, jacquard fabrics, and pile fabrics are 0.14, 0.176, 0.175, and 0.15, respectively. The mesh and jacquard fabrics were observed to have the better tactile comfort properties. In conclusion, the toughness, softness, and bending stiffness of the fabrics had a great influence on the tactile comfort, providing a reference for the development of automotive seat fabrics with good comfort performances.