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In this study, a hydrogel composite adsorbent structure was reported and showed satisfactory adsorption performance. The study uses polylactic acid melt-blown nonwoven fabric to optimize and improve the adsorption performance of the hydrogel. The results show that the nonwoven fabric structure enables the composite material to reach the swelling equilibrium faster than the hydrogel. The adsorption-isotherm model found that the adsorption capacity of composite materials Pb(II) and Ni(II) reached 416.07 and 243.10 mg/g, respectively, and still had high removal efficiency at low pH. The composite material has low cost and can be reused, which solves the problems of difficulty in recovery of the hydrogel adsorbent, low strength, and easy damage, and promotes the industrialization of the hydrogel as an adsorbent.

The chromaticity coordinates and luminance factor are important indicators of the fluorescent dyeing performance of fluorescent dyed fabric. However, with the current bleaching pretreatment process, the chromaticity coordinates and luminance factor of fluorescent yellow dyed modacrylic/cotton blended fabric usually do not meet the requirements of standard ISO 20471. Here we report a new type of bleaching process method via sodium chlorite to solve the problem of yellowing of the background color of the modacrylic/cotton blended fabric. Compared with hydrogen peroxide bleaching, the whiteness of the modacrylic/cotton blended fabric was increased by 13.52% with sodium chlorite bleaching. The color performance analysis showed that the chromaticity coordinates and luminance factor of fluorescent yellow dyed modacrylic/cotton fabric after exposure to xenon light or washing cycles could meet the standard ISO 20471 requirements. Moreover, the fluorescent yellow dyed fabric has good color fastness, such as rubbing resistance, perspiration, laundering at 60°C, and dimensional stability. In addition, the fluorescent yellow dyed blended fabric also has flame retardant performance. Our work may provide a method for the preparation of high-visibility fluorescent yellow fabric with flame retardant performance. It could be used for multifunctional personal protective equipment.

Inspired by pomelo peel, this study designs an effective cushioning composite with a novel sandwich structure using a columnar lattice mold and two-step foaming technique. This sandwich composite consists of a polyamide nonwoven fabric (i.e. nonwoven surface) as the surface reinforcement layer and a double-layered spacer fabric as the bottom layer for energy absorbing. The static-compression resistance and dynamic cushioning efficacy of composites are investigated, examining the influences of three parameters (i.e. the areal density of the nonwoven surface and laminating angle and the mesh size of the double-layered spacer fabric). The experimental results show that the static-compression resistance and dynamic cushioning efficacy of the composites decrease when increasing the laminating angle of the spacer fabric and the areal density of the polyamide nonwoven fabric. By contrast, with an increment in mesh size, the compression resistance and cushioning efficacy of the composites first decrease and then increase. N200PUH/L(S5) consists of a 200 g/m2 nonwoven surface and a 0° laminated angle, 5 mm mesh size double-layered spacer fabric, which exhibits a higher cushioning efficacy than the pomelo peel. The acceleration of N200PUH/L (S5) was 39 g at 15 ms, and the acceleration of pomelo peel was 72 g at 7 ms, which were 60.7% and 28.5% lower than that of the blank group, respectively. The sandwich-structured composites are proven to have promising applications for low-velocity cushioning behavior, and this study combines the textile structure and foam technique, offering a perspective of designing cushioning composite sandwiches for future studies.

Visible light response PAN@Ag-Ag2O/Sch (PAN@AS, schwertmannite and polyacrylonitrile abbreviated as Sch and PAN) nanofibers with different mass ratios were synthesized by electrospinning technology and pH-induced precipitation reaction. X-Ray diffraction, X-ray photoelectron spectroscopy and transmission electron microscopy analysis showed that the formation of Ag-Ag2O/Sch heterojunction and Ag-Ag2O nanoparticles were evenly distributed on the surface of Sch. The prepared nanofibers have high oxidative removal performance for As(III) under visible light. In the PAN@AS0.10 system, the total As removal percent can reach 90.96% after 120 min irradiation at pH 4.0. The scavenger experiments confirmed that the main active substances of the PAN@AS0.10 system were h+ and •OH. The high oxidation and removal performance of the PAN@AS0.10 composite for As(III) was attributed to the effective separation of photogenerated electron-hole pairs and high adsorption capacity of Sch for As under acidic conditions. This research provides a new material for the oxidation and removal of pollutants in water [such as As(III)] and also provides a research basis for the preparation of recyclable photocatalysts.

Metal-organic framework materials not only possess porous structures, but also have excellent antibacterial properties. It is of great practical significance to prepare new antibacterial materials with excellent antibacterial effect by metal-organic framework materials. In our study, Zeolitic Imidazolate Framework-8 (ZIF-8) nanomaterials with antibacterial properties were prepared via the solvent method and diethanolamine template method. The materials were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), cold field-emission scanning electron microscope (SEM), transmission electron microscopy (TEM), N2 adsorption-desorption experiment, antibacterial experiment, and biocompatibility experiment. Results showed that ZIF-8 prepared by solvent method has a more typical hexagonal structure, larger specific surface area, and smaller pore size, and the values are 1812.07 m2g−1 and 2.2412 nm, respectively. At the same time, the materials prepared by the two methods have excellent antibacterial properties, and exhibit good biocompatibility at low concentrations, the antibacterial activity against Escherichia coli and Staphylococcus aureus are higher than 95%, and the cell viabilities of the selected five material concentrations of 12.5 µg mL−1, 25 µg mL−1, 50 µg mL−1, 100 µg mL−1 and 200 µg mL−1 are more than 70%. Therefore, this study provides a feasible method for preparing Nano-scale antibacterial functional particles, and it is of great significance to broaden the application field of ZIF-8 materials and prepare ZIF-8 drug-delivery functional materials.

The recovery of impaired peripheral nerves is often not as expected, which makes the development of nerve conduits trendy nowadays. To enable the neural messages effectively being delivered as well as to prevent the secondary damage during the removal of nerve conduits, the conductivity and biodegradability are two essential requirements for ideal nerve conduits. In this study, electrospinning is used to produce polyvinyl alcohol (PVA)/carbon nanotubes (CNT) electrospun films, after which the morphology analysis, electrical property, water contact angle, and biological characteristics of the membranes are investigated, thereby determining the optimal nerve conduits based on the employment of electrospinning, PVA, and CNT. The test results indicate that with 0.25 wt% of PVA, the electrospun films exhibit comparatively lower resistance of 25.3 ohm, good fibrous morphology with a diameter being 1 μm. In addition, the electrospun films are cytotoxicity-free and facilitate the growth of cells. It is observed in the MMT assay that after co-cultured with cells for three days, PVA/CNT electrospinning fibrous membranes exhibit a cellular viability that is 18.5 times greater than that of the control group on Day 1. According to all property evaluations, PVA/CNT electrospinning fibrous membranes are a qualified candidate for the use of nervous conduits.

Herein, Polyester woven fabrics as the matrices for the experimental group, while cotton knitted fabrics, cotton woven fabrics, and Polyethylene terephthalate (PET) mesh cloth used as the matrices for the control groups, at 40 °e, using 3,4-ethoxylene dioxy thiophene (EDOT)as the polymer monomer, FeCl3as the oxidant, and poly(sodium-p-styrenesulfonate) (PSS) as the dopant, are separately coated with PEDOT:PSS polymer to prepare flexible conductive composite fabrics. The influences of the fabric pattern, oxidant concentration, and monomer concentration on the electrical performance of composite fabrics are optimized. The maximal electrical conductivity of PET-based composite fabrics (218 S/m) occurs when monomer concentration is 0.035 mol/L, the molar ratio of oxidant to monomer is 2.5, and the dopant concentration is 2.5 g/L. Moreover, bacteriostasis rate of this composite fabric reaches 71.8%. Furthermore, by electrocardiogram (ECG) simulated human body unit test as well as human body ECG test, the optimal PET-based composite fabric electrode both has a lower impedance which helps form the stabilized ECG signal. The resulting fabric electrodes retain the soft and breathable advantages from fabrics and reduce the discomfort for a long-term use of conventional electrographic gel, thereby validating the empirical evidence for mobile, portable, wearable ECG electrodes.

For the pursuit of conductive textiles with high electromagnetic shielding performance, specified yarns are processed with a special spinning feeding device with twist counts of 40 T, 50 T, 60 T, 70 T, 80 T, and 90 T, for Next, the optimal yarns from each group are made into SS/Pc-70 and Cu/Pc-80 conductive woven fabrics with a plain weave structure design. In addition, the surface resistivity, electromagnetic shielding effectiveness measurement and air permeability of the two conductive woven fabrics were tested and analyzed. Regarding the electromagnetic shielding performance test, the effects of the complete shielding network, the lamination layers of fabric, and lamination angle on the electromagnetic shielding performance are discussed. The test results indicate that Cu/Pc-80 woven fabrics has the lowest surface resistivity, which means it has the best electrical conductivity; Moreover, different types of metal wires provide the conductive fabrics with different levels of surface resistance. The variations in the lamination angles help attain a complete conductive network that significantly enhances the EMSE, and Cu/Pc-80 have a greater average shielding value comparatively and thus greater EMSE. For both types of conductive woven fabrics, one-layered conductive woven fabrics exhibit the maximal air permeability. As the air permeability of conductive woven fabrics is correlated with the thickness of fabrics, the greater the number of lamination layers, the lower the air permeability of the conductive fabrics.

Exposure to prolonged or excessive noise has been shown to cause a range of health problems. In this study, flexible sandwich composites (FSCs) with excellent sound absorption and mechanical properties were designed and fabricated by a one-step foaming process. The compound fabric as composite panel and fabric sequence contacted with PU foam has been designed and optimized for excellent cushioning and sound absorption properties. In comparisons of three processing methods for fabricating compound fabrics as reinforced panels of FSCs, punching/hot pressing was found to be the most effective method. Through experiments, the L (low-melting polyethylene terephthalate nonwoven fabric, LPNF) -W (warp-knitted spacer fabric, WKSF) -F (flexible polyurethane foam, FPF) composites had the best performance, reaching the sound absorption coefficient of 0.997 (1000 Hz), 107.77 KPa in compression modulus, 6541 N in maximum impact contact force and 44.68% in impact energy absorption. Morphological study revealed that the transition region formed by FPF and WKSF played a vital role in the L-W-F structure. In that region, small cavities and complex porous paths were observed that effectively improved the sound absorption and cushioning properties by dissipating the stress wave and sound wave level-to-level.

The area of forests continues decreasing while the water/soil loss becomes worse. In these complicated environments, mechanical properties, stability, high modulus and low elongation of geotextiles are required. On a premise of the acquisition of good mechanical properties and the improvement in the deformation and puncture resistance of nonwoven fabric, woven/nonwoven hybrid geotextiles are designed and made with needle punch processing technology in this study. The test results indicate that the mechanical properties of hybrid geotextiles are improved significantly when the areal density of nylon fabrics is increased. In particular, with the areal density of 400 g/m2, hybrid geotextiles exhibit the maximal mechanical properties and puncture resistance. Moreover, the pore fraction of hybrid geotextiles decreases as a result of a rise in the areal density of nylon top/bottom layers. The use of a 3 D mesh fabric as the interlayer provides the needle punched composite geotextiles with the highest tensile resistance, puncture resistance. The composite geotextiles are treated with acid and alkali to simulate the corrosion under natural conditions of stabilized soil. The resultant geotextile has good mechanical properties and acid/alkali degradation resistance. This allows the hybrid geotextiles to stabilize water and soil conservation in complicated conditions.

In this paper, a novel facile strategy is reported for fabricating an environment friendly, aging-resistant, and waterproof-breathable fabric using a “pad-knife” coating technique and waterborne polyurethane (WPU) containing isophorone diisocyanate (IPDI) and lignin as an antioxidant agent. Morphology, hydrophobic property, accelerated weathering aging property and artificial degradation performance as well as water vapor transmission and tensile property are characterized. Results show that, IPDI can effectively prevent PU discoloration. Lignin amount affects the morphological structure, tearing strength, WVTR and hydrostatic pressure capability of coated fabrics. Moreover, a 2% lignin addition provides fabrics with enhanced waterproof-breathable properties and tearing strength performance compared with pure WPU coated fabrics after accelerated weathering exposure. The facile coating technology can be applied to protective and functional textiles for military and civil polyester tents.

Geosynthetic clay liners (GCLs) are commonly used in engineering to prevent seepage. These liners’ surface fabric often suffers damage, especially in toxic environments and under high pressure. To mechanically strengthen the GCLs, this study proposes reinforcement by using needle bonding and glass geogrid to establish glass-geogrid-reinforced GCLs (i.e., GGCLs), consisting of glass geogrid, bentonite layer, and 0.3 mm thick melt-blown nonwoven fabric. Tensile durability of GGCLs was determined by exposing them to thermal oxidation and UV degradation. Hydraulic conductivity and heavy metal ions adsorption of GGCLs was explored to simulate the damage caused by garbage leachate. Tensile strengths of polyamide (PA)- and polyethylene terephthalate (PET)-contained GGCLs retained greater than 73% and 90%, respectively, even after 20 h thermal oxidation at 100°C and 60 h UV degradation. Improvement of hydraulic conductivity after 2 h adsorptions of Cu2+, Ni2+, and Pb2+ reached 51.09, 51.04, and 45.56%. The absorptions of Cu2+ and Ni2+ conformed to the quasi-secondary dynamics model, but that of Pb2+ followed both the quasi-first-order and quasi-secondary dynamics models. The mechanical properties and impermeability of the resulting GGCLs declined under the simulated conditions. This study provides a basic theory to predict the durability and adsorption of heavy metal ion of landfill GGCLs under natural and severe weather conditions.

Janus nanofibrous membranes with thin fiber diameter, small pore size, and easy-tailored wettability/thickness gradient have attracted considerable attention in the directional water transport field. However, designing textiles that ensure continuous directional water transport and outstanding moisture permeable, breathable performances has remained a great challenge. In this study, a novel polyacrylonitrile/polyvinyl alcohol–thermoplastic polyurethane (TPU) sandwich nanofibrous membrane with robust moisture permeable, breathable, and directional water transport performance is successfully fabricated with an innovation strategy combining electrospinning with structure-induced method. A good water vapor transmission rate of 9760 g/m2 d and robust breathability of 103 mm/s are obtained by turning the mass ratio of polyacrylonitrile and polyvinyl alcohol and the opening porous structure of TPU; these values are approximately five times those of commercial membranes. The sandwich fibrous membranes are suggested as promising candidates for various applications, especially in moisture-wicking clothing.

In this paper, the shear-thickening fluids(STFs) are prepared by 0.5 µm and 12 nm silica particles. The STFs rheological properties and the performance of stab resistance are studied. SiO2 particles with two sizes (12 nm and 0.5 µm) are mixed at different weight ratios to form shear thickening fluids and its rheological behaviors are tested. Next, the quasi-static spike and knife stab resistances, dynamic impact strength, and yarn pull-out of shear thickening fluid-impregnated Kevlar fabrics are tested. The investigation showed that the micro- and nano-sized particles of silica are present in the compound shear thickening fluid, and the rheological behavior was positively improved. Regardless of whether shear thickening fluid is composed of mono-sized or binary particle-sized SiO2 particles, the presence of shear thickening fluids can significantly strengthen Kevlar fabrics in terms of the quasi-static spike and knife stab resistances, dynamic impact strength, and promote the friction force of inter-yarn. In particular, shear thickening fluid-impregnated Kevlar fabrics have better performances when being composed of 12 nm and 0.5 µm SiO2 particles at ratios of 2:1, 1:1, and 1:2 than when being made of only micro-sized or nano-sized particles.

In this study, wrapping and weaving techniques are used to produce fibrous composites that can block electromagnetic radiation and ultraviolet radiation. Stainless steel filaments are used as the core, and high-strength ultraviolet resistant polyester (PET) filaments are used as the sheath materials to manufacture functional wrapped yarns. The wrapped yarns are made into woven fabric via weaving process. The electromagnetic shielding effectiveness and ultraviolet resistance of woven fabrics are evaluated in order to examine the influence of the number of laminated layer and laminated angles. The test results show that the two-layered woven fabrics that are laminated at 90° have the optimal ultraviolet resistance and electromagnetic shielding effectiveness. Stainless steel/ultraviolet resistance PET woven fabrics are also light weight and can be custom-made into planar protective textile composites based on users’ commands and also can be used in the outdoor domains.

Antibacterial materials are one of the important materials in our daily lives, especially in the medicine where antibacterial efficacy is indispensable. Moreover, the precise electronic instrument also requires highly electromagnetic interference shielding effectiveness (EMI SE) and as such to prevent mutual interference. Therefore, the acquisition of antibacterial property and EMI SE is essential. In this study, carbon nanotube (CNT) and triclosan (TCS) are used as conductive and antibacterial substances separately during the production of polypropylene (PP)-based antibacterial and conductive composite planks. The planks are tested for a series of physical property tests, EMI SE measurement, and antibacterial efficacy as related to the CNT content and the TCS content. The test results indicate regardless of whether it is CNT or TCS that is added, the planks exhibit good crystallinity. Furthermore, the presence of TCS contributes good antibacterial efficacy against staphylococcus aureus (S. Aureus), and the antibacterial efficacy effectuated by 0.1 wt% TCS also meets the related EU standard. In addition, the incorporation of both CNT and TCS adversely affects the EMI SE of the planks, but the resulting EMI SE remains to be between −15 dB and −20 dB.

The study employs the mechanical interlocking theory and hot pressing treatment to generate nonimpregnation of highly rebounding composites. This design preserves the high flexibility, elasticity, and stability of elastic polymer while reserving the skin-friendly feature, resilience, and recovery of the highly elastic nonwoven fabrics without using an adhesive. During the preparation of highly rebounding composites, elastic polymers are hot pressed to form films, after which they are combined with highly elastic nonwoven fabrics. The composites are then examined in terms of the mechanical properties and the level of adhesion. Fluffy nonwoven fabrics and elastomer polymers are hot pressed in order to obtain better adhesion and puncture resistance. The tensile and hammer rebound rate test results show that highly rebounding composites that are reinforced using stiff nonwoven fabrics exhibit greater resilient and tensile properties. Comparing to pure nonwoven fabrics, the proposed highly rebounding composites have a structure that is 1.5 time greater compactness, as well as 1.5 times greater a tensile strength and 1.6 time greater resilience. Namely, they provide great variety according to the users’ ends as their performances are better and adjustable. For example, shallowly or deeply needle punched nonwoven fabrics can be separately used in the garments or cushions. The proposed highly rebounding cushion composites are protective materials and are suitable for the application as in cushions, packaging, and buffering protective equipment.

Nylon fabrics are used as the reinforcing upper layer. A warp-knitted spacer fabric that is saturated with flexible polyurethane foam is used as the lower layer. They are combined in order to form innovative impact energy absorbent composite sandwiches employing a two-step foam process. The quasi-static compressive strength, bursting strength, and dynamic shock cushioning characteristic of the composite sandwiches are evaluated, the latter of which is tested using a drop weight impact tester in order to simulate the impact resistance corresponding to complex environments. The experimental results suggest that a combination of warp-knitted spacer fabric increases the compressive strength and bursting strength of composite sandwiches by 107% and 60%, respectively. The shapes of impactors determine the contact force and dynamic impact time. The greater contact area results in the smaller contact force, indicating that the composite sandwiches have greater cushioning efficacy. Designed with a gradient combination, the flexible polyurethane foam strongly bonds the upper polyamide nonwoven fabric and the lower warp-knitted spacer fabric. The optimal compression resistance, a bursting strength of 1677 N, and a maximum energy absorption of 90% at a 15 J impact energy are presented. The innovative composite sandwiches have a promising perspective in packaging and individual impact protection in the future.

In this study, functional woven and knitted fabrics consist of stainless steel (SS) composite yarns. SS fibers (0.06 mm) and 500 D polyester (PET) filaments are used as the core with 70 D bamboo charcoal (BC) nylon fibers that are being used as the sheath in order to form the functional SS composite yarns. The test results show that the double-layered knitted fabrics have the optimal far infrared (FIR) emissivity of 0.85 ε, while the five-layered composite woven fabrics at 90° lamination angle have the optimal electromagnetic shielding efficacy between −50 dB and −60 dB. It is anticipated that the functional fabrics can be used in protective cloth and safety appliance.

In this study, a new type of flexible sandwich composite with nonwoven facesheets and core reinforced by polyurethane (PU) grid sealing shear thickening fluid (STF) has been presented. With the specific design, the STF was sealed into PU grids as the core to provide shear thickening effect against impact. Rheological property of STF with different mass ratio and PU morphology after first and second foaming were evaluated and optimized for sandwich composite preparation. Both static compression and dynamic impact tests were carried out to obtain the impact dynamic response and investigate the effects of typical parameters including STF volume, core thickness and striker height on low-velocity impact behavior. The test results showed that the optimal concentration of STF was 20 wt.%, whose critical shear rate was 100s−1. The presence of STF had a positive influence on the static compression strength and dynamic impact strength. In particular, the 70% STF volume fraction contributed to the highest compression modulus. The compression modulus was 445 MPa and 466 MPa when the sample thickness was 2 cm and 3 cm, respectively. As for dynamic impact strength with corresponding STF volume fractions, it was 4535.31 mJ for 30%, 4599.72 mJ for 50%, and 4827.46 mJ for 70%, all of which were much higher than that (2348 mJ) of control group (without STF). Regardless of whether the STF volume being 30%, 50% and 70%, the impact displacement of composite was within 10 mm, showing better impact resistance than control group (13.16 mm). Besides, this composite with special PU grid sealing, STF structure demonstrated a certain strain rate effect. The higher the impact energy, the greater the energy absorption was. Specifically, impact energy absorption rate of composite with a thickness of 3 cm was as high as 52.3% under 350 mm impact height.

Terrorist attacks occur constantly, which subsequently arouses awareness of self-protection. In order to alleviate the harm caused by sharp objects of knives and daggers, a design of flexible stab-resistant materials that are impregnated with the shear thickening fluid (STF)/multi-walled carbon nanotubes (MWCNTs) system and different texture of fabrics is presented. STF/MWCNTs are composed of polyethylene glycol (PEG 200) as the dispersion medium and silica (SiO2) of 12 nm and 75 nm as disperse phase as well as MWCNTs as supplementary reinforcement, in expectation to provide the aramid fabrics with high strengths, low critical shear rate, and a short thickening response time. The textures of aramid fabrics—plain (P), twill (T), satin (S), or basket (B) weave—are saturated in the STF/MWCNTs system. The synergetic influences of silica size and texture on tensile strength, quasi-static knife, and spike stab resistances of the STF/MWCNTs-impregnated aramid fabrics are examined. Results show that the plain aramid fabric immersed in the STF/MWCNTs system containing 12 nm SiO2(SM12) exhibit the maximum tensile strength and quasi-static knife stab resistance, 14.7 MPa and 8.9 MPa, respectively, which is 1.15 and 1.43 times higher than pure aramid fabrics. Moreover, the basket-weave aramid fabric immersed in the STF/MWCNTs system containing 12 nm SiO2have the maximum quasi-static spike stab resistance of 17.12 MPa compared to other textures of fabrics, which is 1.05 times higher than those immersed in the 75 nm SiO2STF/MWCNTs (SM75) system and 1.33 times higher than that of pure basket aramid fabrics.

This study proposes composite knits that have multiple functionalities to fit a diversity of applications. Stainless steel/rayon (S/R) wrapped yarns are used as the sheath and bamboo (B) charcoal polyester yarns are used as the core to form SRB wrapped yarns. The SRB wrapped yarns are made at number of twists of 2, 3, 4, 5, or 6 turns/cm. Moreover, the composite knits are made of SRB wrapped yarns as the face yarns and Tetoron® yarns as the ground yarns using a computer jacquard hose machine. The surface resistance, electromagnetic shielding effectiveness (EMSE), elastic recovery, anion release, and softness of the composite knits are measured, investigating the influence of the number of twists as well as the functionalities of the composite knits. When the number of twists is 4 turns/cm, the composite knits have an optimal elastic recovery of above 71.8%, optimal anion release of 408 counts/cm3, a greater softness along the wale direction, and optimal EMSE of 20 dB at frequencies of 2.18E+08 Hz.

The combination of appropriate materials and structural design can compensate for flaw of a single pattern, providing the products with better functionalities. In this study, the custom-made nonwoven fabric machine can unwrap the filament tows before needle punching stage. Sandwich composites are proposed, consisting of two nonwoven fabrics as surface layers and laminated loops of filaments as the core. The puncture resistance of the sandwich composites are examined in terms of weight of filament loops and needle-punching depth, examining their influences. The employment of filaments has a remarkable influence on the mechanical performance of the composites. GF4G has static puncture resistance, dynamic puncture resistance, and bursting strength that are 89%, 30%, 88% higher than those of GF1G; 332%, 127%, and 500% higher than those of 2G; and 671%, 400%, and 1260% higher than those of G. Using filaments to reinforce nonwoven fabrics only requires simple equipment and easy operation. Furthermore, based on the requirements of different final products, diverse filaments and multiple parameters can be combined, thereby providing the composites with efficient production, solid reinforcement, and broad applications.

Engineering design and academic research have been paying more attention to low impact development (LID), one prime development of which is geotextiles. This study uses friction to unwind filament ...

In this study, three differently composed polyurethane (PU) composites are developed and then compared with the pure PU foam in terms of combustion resistance and mechanical properties using the compression test, the drop-weight impact test, the horizontal burning test, and the sound absorption test. Flame-retardant fabric (FRF)-PU is composed of PU foam that is enclosed with two cover sheets of FRFs. FR-PU10 is composed of PU foam that contains 10 wt% of flame-retardant agents. FRF-PU10 is composed of PU foam containing 10 wt% of flame-retardant agents and enclosed by two covers sheets of FRFs. Based on the test results, both FR-PU10 and FRF-PU10 are structurally stabilized and have good combustion resistance. The sample using FRFs as cover sheet had the same combustion resistance property and better compression resistance as the sample using flame-retardant agent. The carbonized layer extinguishes the alighted samples and stops the fire spread right after they are out of the source of fire, suggesting the FRF-PU10 is flame retardant. In addition, FRF-PU10 is easier to process and healthier because of the low use of flame retardants. Therefore, in this study, we proposed PU foam composites have good mechanical and flame-retardant properties and are a suitable candidate for productions of vehicles, plants, construction, and staple merchandises.

In this study, the thicknesswise fibers of the low-melting polyethylene terephthalate (LPET) nonwoven fabrics are needle punched and intertwined with the intra-laminar basalt fibers (BF) of basalt plain woven fabric in order to strengthen the stab-resistant property of LPET/BF sandwich composites as well as to fabricate armor that is composed of less lamination layers. Two LPET nonwoven fabrics and a BF plain woven fabric as an interlayer are laminated and combined using a needle-punch reinforcing method. The response surface analysis based on the Box–Behnken design is used to examine the influences of structure parameters of low-melting PET nonwoven fabrics including areal density (AD) and manufacture parameters including needle punching density (ND), and depth of needle punch (DP) on the spike stab resistance, knife stab resistance, bursting resistance, and tensile property. An empirical regression model of AD, ND, and DP is thereby established. The test results show that the bursting strength and quasi-static stab resistance of sandwich composites are highly dependent on AD and ND. Likewise, DP has a significant influence on the knife stab resistance and bursting strength, while the tensile strength is solely dependent on ND. According to the empirical regress model, the acquired optimal needle punching parameters of sandwich composites are an AD of 400 g/m2, ND of 143.77 needles/cm2, and DP of 6.41 mm. The 95% confidence interval yielded by the empirical regression model is in conformity with the test results. The empirical regression model of the stab resistance is proven to provide effective prediction of the number of lamination layers required by armor in the future.

This study aims to improve the mechanical properties, stabilized structures, and light weight plastic packaging materials to realize diverse applications. A sheet extrusion machine is used to fabricate sandwich-structured composites, which are composed of two polymer cover sheets and a nonwoven interlayer. The samples are prepared in two batches with different cover sheets: thermoplastic polyurethane and polypropylene. Moreover, low-melting-point polyester (LMPET) fibers and Kevlar fibers are fabricated into a LMPET/Kevlar nonwoven interlayer. The laminated composites are evaluated in terms of morphologies, mechanical properties, combustion rates, and thermal behavior. Kevlar fibers are flame resistant and mechanically strong. LMPET fibers promote the interfacial bonding between layers. Thus, the laminated composites are good candidates as packaging materials, and they can be made with rigid or soft materials, depending on specified requirements. Rigid materials can provide higher strengths, and the distribution of fibers thus helps the PP-based laminated composites to obtain higher crystal stability. Moreover, using TPU with flexibility contributes to high extensibility, which grants the laminated composites with high toughness, light weight, and low restriction against the morphology. Such manufacturing is also efficient and economical, thereby satisfying the requirements of plastic packaging materials.

Textiles can have valuable functions in terms of measurement, detection and communication when they are incorporated into functional electronic devices. However, the additional electric circuits limit the flexibility and extensibility, making the wearers uncomfortable and the manufacturing difficult. Therefore, in this study, conductive elastic knits are made of metallic yarns and expected to be used as wearable electronic textiles. In order to retain the flexibility of knits, a crochet machine with jacquard equipment is used to create knit patterns as electric circuits. Regardless of whether it is single-twisted yarn, double-twisted yarn, single-wrapped yarn, or double-wrapped yarn, the metallic wires can be completely covered in polyester filaments. Variations in twist numbers of conductive yarns or knit patterns are beneficial to the tensile strength with a maximum increment of 14%, and changing twist numbers of conductive yarns or knit patterns have a positive influence on the air permeability with a maximum increment of 24%. According to the results of the electric circuit stability test, using double-covered yarns ensures the knits a stabilized electric circuit regardless of the knit pattern.

Fiber-reinforced polymer composites are commonly used in different fields because the evenly distributed fibers in polymer can efficiently transmit the load of a force and mechanically reinforce the polymer matrices. This study proposes producing composite sandwiches using thermoplastic polyurethane sheets as the top and bottom layers and a polypropylene/Kevlar nonwoven fabric the interlayer. Thermoplastic polyurethane sheets and a polypropylene/Kevlar nonwoven fabric are combined using the sheet extrusion method, during which the polypropylene staple fibers are melted and firmly bond the thermoplastic polyurethane sheets. The mechanical properties, thermal behavior, and surface morphology of composite sandwiches are evaluated, examining the influence of parameters. The test results show that the composite sandwiches are mechanically reinforced as a result of using the nonwoven covers. Moreover, the improved interfacial bonding between the cover layers and the interlayer inhibits delamination, and the stabilized structure subsequently decreases the level of combustion which is in conformity of the differential scanning calorimetry results. The manufacturing is creative and efficient due to one-step shaping, creating a refined composite sandwich with good mechanical properties and combustion resistance.

This study aims to propose and obtain rigid foam composites that have features of good sound absorption and electromagnetic shielding effectiveness. Polyether polyol, isocyanate, and distilled wate...

Diverse products are delivered from the production place to different destinations, during which any impacts or shakes easily lead to the damage of products. Buffering packaging materials are thus used to absorb the energy caused by damage, thereby preserving the goods. Buffering packaging materials are commonly made of plastics and foams, which are the materials that have limited buffering effect and cannot be repetitively used. Therefore, this study proposes eco-friendly buffering sandwich-structured composites using thermoplastic polyurethane honeycomb grids and three-dimensional crimped, flame-resistant polyester nonwoven fabrics. Thermoplastic polyurethane honeycomb grids have advantages of a lightweight, a high strength, and high impact resistance. Thus, thermoplastic polyurethane honeycomb grids can be combined with flexible nonwoven fabrics that features ease of process to form environmentally friendly buffering packaging materials. Polyester nonwoven fabrics are made of differing basic weights. A total of one to three layers of polyester nonwoven fabrics serve as the cover sheets of the sandwiches, while a thermoplastic polyurethane grid serves as the interlayer in order to obtain different thicknesses. The buffering sandwiches are tested for bursting strength, air permeability, resilience rate, limited oxygen index, and drop-weight impact test, thereby characterizing their mechanical properties and buffering efficacy. The buffering sandwiches have an optimal residual impact stress of 4762 N when the polyester nonwoven fabrics have a basic weight of 150 g/m2. Moreover, the buffering sandwiches have an optimal resilient rate of 41.8% when they are composed of three-layered polyester cover sheets on both upper and lower sides, and are industrial product that qualified for use as buffering packaging.

This study adopts the melt compounding method to prepare /mutli-walled carbon nanotubes composites. The effects of different lengths of the mutli-walled carbon nanotubes on the isothermal crystallization behaviors, crystalline structure, and thermal stability of the polypropylene/mutli-walled carbon nanotubes composites are examined. The PLM results show that the combination of mutli-walled carbon nanotubes prevents the growth of polypropylene spherulites, and thus results in a small size of spherulites. The differential scanning calorimetry results show that the short (S-) or long (L-) mutli-walled carbon nanotubes can function as the nucleating agent of polypropylene, which accelerates the crystallization rate of polypropylene. Avrami theory analyses indicate that the addition of short-mutli-walled carbon nanotubes particularly provides polypropylene/mutli-walled carbon nanotubes composites with a high crystallization rate. The X-ray diffraction results show that the combination of mutli-walled carbon nanotubes does not pertain to the crystal structure. The TGA test results show that long-mutli-walled carbon nanotubes outperform short -mutli-walled carbon nanotubes in improving the thermal stability of polypropylene, and both can significantly improve it.

This study uses a reactive extrusion for the grafting of maleic anhydride on polylactic acid in order to form polylactic acid grafted maleic anhydride that serves as a compatibilizer between polylactic acid and carbon fiber. The effects of different ratios of the free radical initiator to maleic anhydride as well as the amounts of polylactic acid grafted maleic anhydride on the mechanical properties, interfacial compatibility, thermal behaviors, and electrical properties of the polylactic acid/carbon fiber composites are discussed. The test results indicate that using polylactic acid grafted maleic anhydride as compatibilizer improves the interfacial compatibility of polylactic acid/carbon fiber composites, which in turn contributes to a high electrical conductivity and the electromagnetic interference shielding effectiveness, while decreasing the surface resistance and increases. In addition, the amount of polylactic acid grafted maleic anhydride has a positive influence on their tensile properties, flexural strength, and impact strength. The differential scanning calorimetry results indicate that a high polylactic acid grafted maleic anhydride content is also conducive to crystallinity, but is not in related to the melting temperature. According to the scanning electronic microscope observation, the fractured composites that are inflicted by an impact have considerably few traces of the fibers being pulled out, which is ascribed to polylactic acid that can completely enwrap carbon fiber. Therefore, the incorporation of polylactic acid grafted maleic anhydride is proven to strengthen polylactic acid/carbon fiber composites, exemplified by their improved interfacial compatibility and properties.

The current study fabricated nylon/high-resilience bonding polyester (HRPET) nonwoven fabric with various needle-punching parameters and investigated the effect of these variations on the response of high-density flexible foam under static loading and low-velocity impact. The needle-punching depth and frequency are selected as variations. The HRPET fiber generates bonding-points when being thermally treated, which provides resilience properties on the sandwich flexible composites. The results find a substantial relationship between the temperature of thermal treatment and the absorption of low-velocity impact energy which is mainly because of the increase of fiber connection force. The impact force is eliminated by 8255 N at most. Needle-punching depth contributes to resistance to static loading and the highest resistance was 2043 N.

This study prepares and explores the properties of three types of woven fabrics that have electromagnetic shielding effectiveness (EMSE), far infrared (FIR) emissivity, or both (EMSE/FIR). The EMSE woven fabrics use stainless steel (SS) staple blended yarn and the FIR woven fabrics use FIR polyester filaments. The woven fabrics are made with various structures, densities, lamination layers, and warp/weft arrangements in order to yield the optimum EMSE and FIR emissivity. The experimental results show that an increase in SS content slightly increases the EMSE at the frequency range between 300 and 600 MHz, but does not significantly increase the EMSE at a high frequency of between 2000 and 2200 MHz. However, using SS staple blended yarn for both the warp and the weft significantly increases the EMSE by between −8 and −16 dB. The FIR emissivity increases as a result of an increasing amount of FIR polyester filament and reaches the optimum, 0.88.

Research on the simulation and modeling of dynamic puncture penetration is more complex problem due to full consideration of the tightness of the fabric and the sharp profile of the puncture. This study presents numerical simulation of complicated dynamic puncture behaviors on the basis of the roles of extension and stress-wave transmission on the deformation. The unit cell model was used to simulate the yarn crimp and extension during the uniaxial dynamic puncture process. In addition, the puncture deformation and stress distribution of woven fabrics with different elastic modulus and friction distance were simulated followed with dynamic puncture penetration. The result shows that dynamic puncture damage critically depends on the elastic modulus of yarns and the distance between yarns; the inter-yarn distance affects dynamic puncture resistance more significantly. Dynamic puncture stress nonlinearly increases with the elastic modulus, and linearly decreases with yarn distance. The research result indicates that weaving density can be increased to improve dynamic puncture resistance more obviously.

To improve the wearing comfort, durability, and antibacterial properties of the electromagnetic (EM) shielding property, a type of multifunction EM shielding woven fabrics which having great liquid transport and drying ability were fabricated in this study. This study aims to investigate theirs liquid transport, drying, and electromagnetic (EM) shielding properties. For this purpose, initially six types of multifunctional crisscross-section polyester (CSP)/antibacterial nylon (AN)/stainless steel wire (SSW) metal hybrid yarns with different wrapping amounts were produced using hollow spindle spinning technique. Conductive woven fabrics were then woven with CSP/AN/SSW metal hybrid yarns as weft yarns, and PET filaments as the warp yarns. The liquid transport and drying ability of the conductive woven fabrics were evaluated in terms of wicking ability and water evaporation rate, which are two vital factors that affect the physiological comfort level of personal protective clothing (PPC). Results indicated that adding CSP yarn in the fabricated EM shielding woven fabric could obviously improve the drying rate of the fabric. The EM shielding behavior of these woven fabrics were analyzed using a vector network analyzer in the frequency range of 300 kHz–3 GHz. Results showed that the wrapping amounts of the metal hybrid yarns significantly affect the wicking and drying abilities of the woven fabrics. In addition, the lamination angles of the fabrics with different amounts of layers remarkably affect their EM shielding characteristics.

A new approach for intra-/inter-laminar reinforcement using needle-punching and thermal bonding was proposed for improvement of puncture resistance of multilayer compound fabrics that were composed of different kinds of nonwovens and woven fabrics. Effects of woven fabric orientation and thermal bonding on static and dynamic puncture properties were explored. Multilayer compound fabrics with different compositions of nonwoven and sequence of woven fabrics were comparatively discussed to confirm fabric and nonwoven influencing on static and dynamic puncture resistances. Puncture resistance mechanism of plied orientation and thermal bonding was analyzed for multilayer compound fabrics. The research result shows that woven fabric orientation affected static and dynamic puncture resistances more significantly when multilayer compound fabrics were comprised of high-modulus nonwovens and woven fabrics. Plied orientation correlated with the yarn density of woven fabric that was contained in compound fabrics. Contact length between woven fabric and nonwoven, as well as specific fiber toughness from nonwoven, was respectively responsible for static and dynamic puncture resistances of multilayer compound fabrics.

This study proposes to make geotextiles from recycled materials. Polyester fibers, recycled polyester fibers, and low melting point polyester fibers are blended and needle punched to make the polyester fabrics, the mechanical properties of which are then evaluated to determine the optimal parameters. The polyester nonwoven fabrics are needle punched with various densities. Afterwards, the resulting polyester nonwoven fabrics, glass fiber woven fabrics, and polypropylene selvages are combined, needle punched, and hot pressed to form geotextiles, the properties of which are tested by tensile strength, tearing strength, burst strength, puncture strength, and water resistance tests. The test results show that polyester fabrics containing 50 wt% of polyester fibers have the optimal mechanical properties. Furthermore, needle punching at 90 needles/cm2 results in a greatest increase in mechanical properties of the polyester nonwoven fabrics. The tensile strength, tearing strength, and water resistance of the geotextiles increase as a result of hot pressing, and the bursting strength and puncture resistance are primarily associated with the needle punching densities. This study successfully creates composite geotextiles with reinforced mechanical properties by needle punching and hot pressing recycled polyester fabrics and polypropylene selvages.

Geotextiles primarily provide reinforcement, and their tensile properties can resist stresses and prevent soil structure deformation. Nonwoven geotextiles are also commonly used in railways, roads, soil and water conservation, and therefore their applications are subjected to climatic environments and geographical environments where the geotextiles are used. Therefore, this study recycles and reclaims Kevlar selvages that are then incorporated with polyester fibers and low-melting-point polyester fibers in order to form nonwoven geotextiles. The tensile properties of the geotextiles in relation to various ambient environmental temperatures are examined with the test temperatures being set as 25℃ (control group), 50, 60, 70, and 80℃. Statistical analyses are performed to examine the effects of fiber blending ratios, needle punching depth, and thermal treatments on the tensile properties of the nonwoven geotextiles. The test results indicate that nonthermally treated nonwoven geotextiles have a tensile strength that is significantly increased when the ambient temperature is increased. In contrast, according to the insignificant differences obtained from statistical analyses, the tensile strength of thermally treated samples is independent of the ambient temperatures, indicating that thermal treatment allows for heat setting of the geotextiles. In particular, the thermally treated polyester/low-melting-point polyester/Kevlar nonwoven geotextiles have the maximum tensile strength when they are composed of a blending ratio of 60/20/20 wt% and a needle punching depth of 0.5 cm.

Composites comprising a braided poly(lactic) acid (PLA) filament and calcium phosphate bone cement (CPC) were inferred to maintain space and to pack porous fillers into restorative sites. Composites of alkalized multilayer-PLA braids and CPC (PLA/CPC) were divided into various groups according to a series of heat-treatment periods that lasted for 60, 90, 120, 150, and 180 min at 160℃; subsequently, these composites were characterized. Strength decays of samples were also compared after 24 h immersion in Hanks’s physiological solution. Results showed that the PLA/CPC specimens were toughened after treatment at 160℃ for 120 min. Furthermore, the moduli of PLA/CPC groups increased significantly when the heating time was more than 150 min; this effect was generated by the cold crystallization within the PLA filaments. The reduced stress in the composites after immersion was attributed to the fibers that protruded from the scaffold surface and to hydrolysis. The mechanical test results for the PLA/CPC composites indicated that the toughening effect was strengthened significantly under prolonged heat treatment, especially when the heating time was longer than 150 min. The cold crystallization degree of PLA increased, thereby enhancing the strength and toughness of a specimen before immersion. Thus, PLA/CPC composites can be used to simulate potential bone functions as well as to maintain three-dimensional spaces and pack porous fillers into restorative sites conveniently.

This study examines how inter/intra-ply hybrid structures influence the impact load of sandwich-structured flexible composites determined by static or low-velocity impact tests. The flexible composites are composed of nylon/high-resilient non-woven polyester fabrics as the surface sheet and polyurethane foam as the core layer. The polyurethane foam layer has a specified thickness and density, while the surface layers comprise various fiber blending ratios, different blending methods, different lamination procedures and lamination orders. The test results show that the flexible composites have an optimal impact absorption of 1901 N for a static impact when the nylon/high-resilient polyester non-woven fabrics are composed of an inter-ply hybrid structure. In contrast, they have an optimal impact absorption of 8255 N for a low-velocity impact when the nylon/high-resilience polyester non-woven fabrics are composed of an intra-ply hybrid structure.

This study melt-blends polypropylene (PP), wood flour (WF), and far-infrared masterbatches into PP/WF wood plastic composites with far-infrared emissivity. During the process, maleic anhydride-grafted polypropylene (PP-g-MA) is added as the coupling agent between PP and WF. Mechanical property tests, scanning electron microscopy, X-ray diffraction (XRD), differential scanning calorimetry (DSC), polarized light microscopy (PLM), and far-infrared emissivity are undertaken to evaluate various properties of the PP/WF wood plastic composites. The test results show that regardless of the WF content, mechanical properties of the composites remain at certain levels. The combination of 3 wt% PP-g-MA increases the interfacial adhesion between WF and PP, which in turn effectively increases the tensile strength by 20% and increases the flexural strength by 35%. The PP/WF wood plastic composites containing 4 phr (parts per hundreds of resin) of far-infrared masterbatches is 0.86 ɛ, which reaches the standard of good health care. The test results of XRD, DSC, and PLM show that the combination of both WF and far-infrared masterbatches helps the heterogeneous nucleating in PP, and increases the crystallization temperature of PP, but does not influence the crystalline structure of PP.

In this study, far-infrared/anion-releasing elastic warp-knitted fabrics were successfully fabricated. Firstly, the composition and twist degree of ring-spun complex yarns that were made by rotor-twisting machine and ring-spinning frame were optimized based on twist contraction, hairiness, and tenacity measurements. The shell materials—1-ply bamboo charcoal (BC) roving, 1-ply phase change material (PCM) or the both (BC/PCM), and the core material—BC/stainless steel (BC/SS) wrap yarn, were formed into different compositions of ring-spun complex yarns. Afterward, elastic warp-knitted fabrics were fabricated using the optimized complex yarns as weft yarns, and rubber threads and polyester (PET) filaments as warp yarns. Air permeability, far-infrared emissivity, and anion amount of resulting warp-knitted fabrics were evaluated. Ring-spun complex yarn result shows that, twist contraction rate ratio increased, but hairiness decreased with increase of twist degree. Tenacity of ring-spun complex yarn made by BC roving (Type A) or PCM roving (Type B) first increased and then decreased with twist degree. However, when 1-ply BC and 1-ply PCM rovings were used as shell materials, the tenacity of resulting ring-spun complex yarn (Type C) decreased with twist degrees. Consequently, 12 twists per inch (T.P.I.) was the optimal twist degree for the following fabrication of warp-knitted fabrics. Air permeability, far-infrared emissivity, and anion amount of elastic warp-knitted fabrics composed of BC/SS wrap yarn and BC roving reached 44.35 cm3/s/cm2, 0.94ɛ and 420 counts/cm3, respectively, indicating excellent breathability and far-infrared/anion-releasing health care functions.

A new acoustic absorbing/cushioning composite is fabricated by thermoplastic polyurethanes honeycomb structure – thermoplastic polyurethane honeycomb cushion and grid, and composite nonwoven in this study. Composite nonwoven is composed of different layers of polyester/polypropylene nonwoven and polyester nonwoven. Research result shows that layer combination of polyester/polypropylene nonwoven and polypropylene nonwoven affects acoustic absorption and thermal conductivity of resulting composite nonwovens. The thermal conductivity of composite nonwovens decreases to 0.02213 W/(m K), showing excellent thermal-insulating property. Honeycomb structure–thermoplastic polyurethane honeycomb cushion and grid broadens the acoustic absorbed frequency and improves the mid- and high-frequency absorption coefficient and cushioning property of thermoplastic polyurethane/polyester/polypropylene composites. Incorporation of different honeycomb structure into composite nonwovens presents diversified acoustic-absorbing characteristic profiles. The resulting 35-mm-thick thermoplastic polyurethane/polyester/polypropylene composites absorb 85% acoustic waves at 1250 Hz and 94.2% at above 2000 Hz as well as 92.88–96.59% impact energy. Therefore, it becomes an excellent alternative for protective wall in kindergarten and gerocomium and compartment wall in the building.

Twisting is an important process in the manufacture yarns for textiles and has an influence on woven fabrics, knitted fabrics, and braided fabrics made with such yarns. This study aims to determine how twist coefficients and thermal treatment temperatures influence tensile strength, elongation, and elastic properties of the resulting wrapped yarns. Polyester (PET) yarns and spandex fibers were twisted into PET/PET wrapped yarns and PET/spandex wrapped yarns, and during the process the thermal treatment temperatures as well as twist coefficients controlled by rotor speed were changed. The results show that variations in twist coefficient do not influence the tensile strength and elongation of the PET/PET wrapped yarns. However, an increase in twist coefficient results in an increase in tensile strength and a decrease in elongation of PET/spandex wrapped yarns. The elongation of PET/spandex wrapped yarns thermally treated at 160℃ is lower than that of untreated PET/spandex wrapped yarns by 86%. In addition, the residual stress and permanent deformation of PET/spandex wrapped yarns both decrease as a result of the increasing thermal treatment temperature.

This study uses metallic wires, stainless steel (SS) wires, and copper (Cu) wires as the core and 75 denier polyester (PET) fibers as the wrap material to form the metal/PET wrapped yarns. The optimal SS/PET and Cu/PET wrapped yarns are then made into different woven fabrics. The test results of the metallic wrapped yarns show that the optimal tenacity occurs with the wrapping count being 12 turns/cm, while the metal/PET woven fabrics have a low surface resistivity due to the conductive metal/PET wrapped yarns along the weft direction. An increasing number of laminating layers increases the electromagnetic shielding effectiveness (EMSE) while decreasing the air permeability of the woven fabrics. The laminating angle is also proportional to the EMSE of the woven fabrics. In sum, the combination of metal wires and PET fibers provides the resulting woven fabrics with good EMSE.

In this study, hybrid composites composed of high-resilience fiber and reinforced with glass fabric were successfully prepared by needle punching and thermal bonding process. The effects of areal density, needle punching depth, and fiber blending ratio of the composites on delamination, cushioning, hardness, support factor, and hysteresis loss were investigated, and the relevant mechanisms were elucidated. Experimental results indicated that the hybrid composites exhibit high cushioning properties under multidrop-weight impact. The factors studied considerably influenced the cushioning properties of the composites. Hardness and support factor improved with increasing areal density and needle punching depth but decreased with increasing crimp hollow fiber ratio because of compression stress relaxation. Hybrid composites with various areal densities exhibited contrasting effects on the hysteresis behaviors of compression and indentation force deflections; these effects are attributed to the dissipation of support and energy in the materials surrounding the indentation. Instantaneous compression and recovery processes yielded no significant effects on fiber slippage; however, hysteresis loss was slightly affected by compression stress relaxation. The high-resilience thermal-bonding hybrid composites proposed in this work exhibited high cushioning and compression resistance properties.

The purpose of this study was to evaluate the moisture transport and dynamic elastic recovery (DER) properties of the multifunction elastic warp-knitted fabric that may be used in electromagnetic shielding personal protective clothing (PPC) to protective wearers from electromagnetic radiation and other occupational hazards. The wicking behaviors of the produced elastic warp-knitted fabrics in terms of vertical wicking, horizontal wicking, transfer wicking, and siphon wicking abilities were discussed. The obtained results showed that increasing the amount of crisscross-section polyester yarns had a significant influence on the wicking behavior of the produced elastic warp-knitted fabrics. Moreover, the stretch and recovery properties of the produced elastic warp-knitted fabric caused by bodily movement were also assessed in terms of DER values at different extension levels of the fabric. The results indicated that increasing the extension level would affect the residual energy in the fabric and increase the stress values to the skin. These results provide a better understanding of the characteristics of these elastic knitted fabrics prior to use for tight-fit PPC.

In order to realize recycling of polypropylene selvages, polypropylene nonwoven selvages with different plied orientation were inserted between Kevlar/Nylon/low-melting polyester nonwoven fabrics forming composite nonwoven. Low-melting polyester content of nonwoven fabric and hot-pressing temperature of composite nonwoven were both optimized after static and dynamic puncture resistances. Moreover, effects of hot-pressing and plied orientation on static and dynamic puncture resistances, sound absorbing and thermal insulating properties of composite nonwoven were discussed respectively. Result shows that, optimal low-melting polyester fiber content was 30%, and best hot-pressing temperature for composite nonwoven was 180°C. Polypropylene nonwoven selvages improved static puncture resistance, sound absorbing and thermal insulating properties. Hot-pressing slightly increased puncture resistance and obviously improved thermal insulation, but decreased sound absorption coefficient significantly. Plied orientation affected static and dynamic puncture resistance insignificantly, but influenced on sound-absorbing and thermal-insulating properties significantly. When composite nonwoven was plied with 90°/90° polypropylene selvages and hot-pressed at 180°C, the static and dynamic puncture resistances reached 120 N and 80 N, respectively, and thermal conductivity was 0.047 W/mK. Five layers of composite nonwoven before hot-pressing had sound absorption coefficient of above 0.94 at frequency of higher than 1890 Hz.