Fibers and Polymers最新文献

Tomato pruning residues were valorized as cellulose fibers using a mild and sustainable soda-pulping process. This approach achieved a high cellulose content exceeding 40% and fibers with a length of less than 0.55 mm. These cellulose fibers were incorporated into bio-based polyethylene (BioPE) to develop biocomposites that exhibited enhanced properties suitable for food packaging applications. The mechanical properties of the biocomposites were optimized by adjusting the concentration of the coupling agent (MAPE). A concentration of 9% MAPE yielded the highest tensile strength, attributed to improved interfacial adhesion, as confirmed by SEM analysis. Furthermore, the integration of tomato fiber (TF) demonstrated a positive impact on the mechanical properties, resulting in a 12% increase in tensile strength and a noteworthy 109% increase in flexural strength at a 40% TF loading in comparison to pure BioPE. The presence of TF significantly enhanced the water absorption capacity of the biocomposites, achieving a remarkable increase of 4000%, while maintaining the thermal stability of the polymer matrix. The lignin inherent in the fibers contributed to antioxidant properties and reduced bacterial adhesion, particularly against S. aureus and E. coli, with optimal results observed at intermediate fiber content levels of 20–30%. However, excessive fiber loading may lead to diminished heat seal resistance due to heterogeneity introduced in the polymer matrix. The findings indicate that TF-reinforced BioPE biocomposites represent a promising sustainable material for food packaging. These materials effectively combine improved mechanical performance, bioactivity, and environmental compatibility, positioning them as a viable alternative in the packaging industry.

Graphene materials can emit far-infrared radiance, and existing studies have confirmed that graphene far-infrared radiation can promote microcirculation and promote locomotor ability. To study the effects of graphene content and knitted fabric structure on exercise-induced muscle fatigue, 12 kinds of specimens were prepared, including 4 kinds of far-infrared nylon yarns with graphene content and 3 kinds of tissue structures. Subjects wore different knitted pants and muscle fatigue was induced through jogging, with rectus femoris muscle activity monitored via surface electromyography. Results demonstrated that graphene far-infrared nylon fiber knitted pants significantly reduced exercise-induced muscle fatigue, and the type of face yarn was the main factor affecting the degree of muscle exercise fatigue, and the sweatpants with graphene added had a low degree of muscle fatigue at the rectus femoris muscle, and the tissue structure would also affect the degree of muscle fatigue, the 1 + 3simulated rib showed better anti-fatigue effect due to the thicker structure. Among them, the sample with 0.4% graphene content performed the best, and its rectus femoris fatigue threshold reached 214.10 s, which was 21.5% higher than that of the pure nylon control group.

A yellow natural dye from wood extract of Arcangelisia flava (L.) Merr. was investigated to dye cotton fabrics. In the preliminary phytochemical screening, the aqueous extract of A. flava stem was found to contain tannins/phenolic compounds, flavonoids, alkaloids, and saponins. Several types of mordants such as alum (Al³⁺), lime (Ca²⁺), and ferrous sulfate (Fe³⁺) were used in the dyeing process using three different techniques: pre-mordanting, meta-mordanting, and post-mordanting. The colorimetric data (L^*, a^*, b^*) and color strength (K/S) were measured for the characterization of the dyeing result. Alum was found to be a good mordant to achieve the best results of a bright and desirable yellow color. In this research, the influence of alum mordant concentration on color parameters and wash fastness rating was also conducted. An increasing trend in the K/S value and wash fastness performance of dyed samples was observed: post-mordanting > meta-mordanting > pre-mordanting. The 20% alum post-mordanted sample shows the highest K/S value of 14.19. The post-mordanting method provides the best washing fastness properties compared to other mordanting methods in the range of 4–5 (color change) and 3 (staining change). The higher the concentration of alum tended to increase the color strength of samples in pre-mordanted samples. However, the variation of alum mordant concentration did not significantly influence the wash fastness of the dyed cotton fabrics.

Graphene not only provides functional finishing for fabrics, but also influences the original physical and mechanical properties of the fabrics, reducing their wearing properties. This study conducted graphene conductive finishing on acrylic/wool blended knitted fabrics using an oxidation–reduction method. The research focused on analyzing the reduction of graphene, fabric conductivity, thermal comfort, and hand feel of the fabric, while studying the effects of reduction temperature and time on electrical conductivity, thermal comfort, moisture absorption, breathability, and hand feel during the graphene process. The results revealed that a higher degree of graphene reduction led to lower surface resistance and enhanced electrical conductivity in the acrylic/wool blended knitted fabrics. The stability of the fabric structure and mechanical characteristics were also influenced by temperature and time, impacting comfort attributes. The reduction temperature and duration directly influenced the reduction degree of graphene, with the maximum reduction degree and lowest surface resistance observed at 75 °C and 90 min. Importantly, there was no significant degradation in the thermal comfort and tactility of the acrylic/wool blended knitted fabrics.

Here, we innovatively prepared a novel breathable, waterproof and windproof micro/nanofibrous membrane for a variety of potential applications, such as protective clothing, sports clothing, and filter media. The membrane consists of a thin layer of electrospun poly(vinylidene fluoride)/polyurethane nanofiber layer containing silica nanoparticles (PVDF/PU–SiO₂) over the hydrophobic polysulfone (PSF) hollow fiber layer. The effects of electrospinning time (3–5 h) and PSF hollow fiber layer grammage (1.5–2.5 g) on the breathability and barrier performance of micro/nanofibrous membrane were evaluated. Fabrication of uniform and bead-free PVDF/PU-SiO₂ nanofibers over the PSF hollow fiber layer was confirmed by electron microscopy. The resulting micro/nanofibrous membrane‐based clothing system was endowed with an increased water vapor transmission rate (WVTR) of 14,271 g/m²/day, suggesting its high breathability and body-generated moisture transferability. Benefiting from combining PVDF/PU–SiO₂ nanofibrous layer and microporous PSF hollow fiber membrane, significant waterproofness was achieved with high water contact angle (WCA) of 139° and hydrostatic pressure of 410 mmH₂O. In addition, exploring the windproof properties of developed micro/nanofibrous membrane revealed high air permeability value of 5.85 mL/cm²/s. Furthermore, the micro/nanofibrous membrane exhibits good physical and comfort properties, with a bending length and a crease recovery angle (CRA) of 14.43 cm and 115°, respectively. Unlike previous single-layer membranes, the developed bilayer PSF-PVDF/PU–SiO₂ micro/nanofibrous membrane leverages the microporous PSF hollow fiber layer to ensure structural integrity and moisture diffusion, while the PVDF/PU–SiO₂ nanofibers provide outstanding hydrophobic properties and precisely adjustable pore structure for improved barrier performance. This hierarchical design demonstrates great potential for advancing next-generation sports clothing technologies.

The increased use of sustainably sourced plant-based material in the development of 3D printing material has consequentially increased the industrial potential of locally produced plant-based waste in the GCC and wider Arab Peninsular region. As a result, waste sourced from olive trees, one of the most common trees in the region, can be repurposed for the aforementioned 3D printing applications. Furthermore, the use of an extruder to blend samples of commonly used polymers such as PLA and assorted filler material has made the creation of blended-material filaments for 3D printing possible. This study seeks to put the extrusion and testing processes as well as the viability of olive leaf waste as a blend material to the test through the preparation of multiple blending proportions, the variation of processing parameters, and the variation of testing parameters to ascertain the optimal process for the production of filaments of this nature as well as identify the most suited filament for 3D printing applications. The design of this study is modeled and analyzed using predictive Taguchi Analysis, Analysis of Variance (ANOVA), and Grey Relational Analysis. The study points toward a blend proportion of 4% as being the optimum choice for the extrusion of a PLA-OL waste filament—this conclusion was reached after results from the tensile testing of 9 different runs pointed toward the 4% blend as being better able to extrude filaments that produced stronger mechanical properties. The study also identifies the strain rate of 2.5 mm/min as being the optimal strain rate under which tensile testing should be conducted to better gauge the strength of the filaments due to its correlation with better results across multiple mechanical properties, including Ultimate Tensile Strength, Young’s Modulus, and Toughness. The blend proportion was found to contribute the most toward the mechanical performance of the filaments, followed by the strain rate, and finally by the extrusion temperature.

Response Surface Methodology (RSM) was employed to optimize the activation yield (%) and specific surface area (m²/g) in the manufacture of activated carbon fibers. Isotropic petroleum pitch was melt‑blown into non‑woven webs (~ 25 µm), then stabilized (280 ℃, air), carbonized (800 ℃, N₂), and steam‑activated (800–900 ℃) as discrete steps. A Box-Behnken Design (BBD) that encoded eight process variables spanning stabilization, carbonization, and activation generated a second-order polynomial model (R² = 0.969 for yield and 0.918 for surface area). According to the RSM model, the key process variable for achieving a high activation yield was the stabilization holding time, with optimal results observed at 1 h. The main process variable for maximizing the specific surface area was the activation temperature, with the optimum value being 900 ℃. Validation under the predicted optimum (900 ℃, 1.2 g/min steam, 45 min) produced ACFs with 34.6 wt. % yield and 2,429.5 m²/g surface area, confirming the model’s predictive accuracy. These results confirm that RSM offers a statistically robust route to tailoring pitch-based activated carbon fibers (ACF) for high-performance adsorption applications.

Phenolic compounds are a class of compounds with a wide range of positive biological functions and are the main pigment components in various natural-colored fibers. Common representative fibers containing phenolic compounds include white silk, green silk, brown cotton, and green cotton. The comprehensive antioxidant capacity of these fibers depends on both the content and properties of their phenolic constituents. Furthermore, the solubility of phenols influences the potential dermal absorption of pigments during wear. Given that phenolics in natural fibers may exert distinct effects upon skin contact, we optimized a method for quantifying the molar concentration of phenolic mixtures to systematically compare the physicochemical and biological impacts of phenols derived from different fibers. From the fiber perspective, green silk has the strongest antioxidant activity, which is related to its extremely high phenolic content. However, when evaluated at equivalent molar concentrations, phenols extracted from white silk demonstrated the highest free radical scavenging rate. Utilizing the molar concentration quantification method for further research, phenols in silk and green cotton have no significant toxicity to normal cells. Meanwhile, phenols from green silk and brown cotton significantly inhibited malignant melanoma cell growth. Comprehensive analysis indicates that among phenolic-containing fibers, green silk represents a material combining non-toxicity with potent antioxidant and anticancer properties.

In the current field of wearable technology, silver yarns are used to provide electrical conductivity to non-conductive textile fabrics required for monitoring and measurement. This work aims to provide an alternative to silver yarn by exploring innovative methods to integrate 3D-printed circuitry onto textile fabrics to offer an ideal solution for prototyping textile-based wearable technology products. For the first time, different conductive composite filaments were investigated for both improved electrical conductivity and drapability. Specimens were fabricated by 3D printing electrically conductive material on a textile fabric between two disconnected squares made of knitted silver yarn. Electrical conductivity and drapability were two design objectives. 3D printed samples were made from off-the-shelf conductive composite filaments: two carbon black/PLA filaments and one copper/polyester filament. All samples are manufactured using a Material Extrusion 3D printer. The impact of trace patterns, width, and thickness on electrical conductivity on a hard surface and textile fabric was evaluated along with drapability. The copper/polyester trace integrated onto the textile through 3D printing was found to have electrical and draping performance similar to the reference textile fabric made with silver yarn. The S-pattern geometry with a 2.5 mm trace radius, 4 mm width, and 1.5 mm thickness was best for electrical performance, possessing a resistance of 3.58 Ω/cm and draping coefficients of 45.3% along the trace and 61.1% across the trace. The S-pattern geometry with the same width and thickness, but a 5 mm trace radius, exhibited a slightly higher resistance of 4.76 Ω/cm but lower draping coefficients of 35.8% and 57.7% along and across the trace, respectively. This made it a better choice for applications where enhanced drapability is critical.

The 2/2 twill pattern represents a configuration of two-dimensional (2D) fabric weave. Composites reinforced with this architecture exhibit in-plane symmetry and balance, even as single layers, and offer superior formability. However, the inherent undulation of the interlaced yarns leads to reduced compressive strength. This study introduces an analytical approach to evaluate the compressive behavior of such composites. In the 2/2 twill configuration, both the warp and fill yarns comprise alternating straight and curved portions. The curved sections are treated analytically as beams resting on an elastic foundation. The model accounts for all three key structural components of the laminate, namely longitudinal yarns, transverse yarns, and the surrounding matrix. Load distribution among these constituents under compression is systematically assessed, and the internal stress field is computed. Progressive failure of elements is incorporated into the analysis. Experimental validation was performed using T300/5208 carbon/epoxy twill weave composite specimens.