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In this study, the coating process is employed on metal wire to help improve the friction resistant property of carbon fibers, thereby provides more application feasibility. The yarn coating technique for reinforcement and woven fabric process are used to produce carbon/stainless steel/polyester/polypropylene/acrylic (CSPPA) woven fabrics that are characterized with softness and a light weight. The constituent coated yarns exhibit good conductivity after being coated with a PP layer, and likewise strengthen the woven fabrics in terms of mechanical behavior of tensile strength, elongation, bending torsion, creep resistance, and wear-resistant properties. The test results indicate that in the woven process, samples retain good morphology. Due to PP sheath, the tensile strength of woven fabrics increases from 23 MPa to 42 MPa. Although the lamination layer numbers does not improve the EMI SE of woven fabrics, the EMI SE still reaches over 40 dB. The manufacturing design proposed in this study provides an innovative finishing for carbon fibers without affecting the intrinsic properties, and provides a greater range of application for carbon fibers.

People have increasingly rising health consciousness in recent years and researchers are thus devoted themselves to develop multi-functional textile products. In this study, stainless steel (SS) filaments are used for electromagnetic shielding effectiveness (EMSE) while polypropylene (PP) filaments are used for ultraviolet resistance and good mechanical properties. Spinning and weaving continuous formation techniques are employed to produce wrapped yarns with SS and PP filaments, after which a weaving process is employed for the preparation of SS/PP woven fabrics. The woven fabrics are tested for EMSE and UV resistance, examining the effect of the lamination-layer numbers and lamination-layer angles. Test results show that the optimal EMSE and UV resistance occur when SS/PP woven fabrics are laminated with two layers at 90 °. Not only focus on the mechanical performance, the proposed woven fabrics with good EMSE, UV resistance, and a light weight, and are good candidate for a variety of application as required. The proposed UV resistance and EMSE woven fabrics significantly increase the additional values of traditional textiles.

In this study, shape memory polyurethane (SMP) foaming material is used as the main material that is incorporated with carbon fiber woven fabrics via two-step foaming method, forming sandwich-structured composite planks. The process is simple and efficient and facilitates any composition as required. The emphasis of this study is protection performances, involving puncture resistance, buffer absorption, and electromagnetic wave shielding effectiveness. The proposed soft PU foam composite planks consist of the top and bottom PU foam layers and an interlayer of carbon fiber woven fabric. Meanwhile, PU foam is incorporated with carbon staple fibers and an aluminized PET film for reinforcement requirements and electromagnetic wave shielding effectiveness, respectively. Based on the test results, the two-step foaming process can provide the PU foam composite planks with excellent buffer absorption, puncture resistance, and electromagnetic wave shielding effectiveness; therefore, the proposed composite planks contribute a novel structure composition to SMP, enabling it to be used as a protective composite. In addition, the composites contain conductive material and thus exhibit a greater diversity of functions.

This study investigates the mechanical properties and damage behavior of flexible laminated composites. Needle punching is performed to combine woven Kevlar fabric and two nonwoven low-melting point polyester (LMPET) fabrics into a fabric interlayer. A sheet-extrusion machine is used to bond two thermoplastic polyurethane (TPU) sheets on each side of a fabric interlayer. The tensile strength, peel load, and static puncture resistance of the flexible laminated composites are evaluated, and the influences of needle-punching rates and depths are examined. Test results show that a high needle-punching rate or depth positively affects tensile strength by promoting fiber entanglement. The tensile strength of the 300-15 group reaches 24.70 MPa. Moreover, when the needle-punching depth does not exceed 11 mm, melted LMPET fibers help bond two-phase materials and thus increase the peel loads of the final composites. The 200-11 group has an optimal puncture resistance of 5.86 N. The combination of TPU sheets and woven Kevlar fabrics yields flexible laminated composites with good static puncture resistance. The results of this study can be applied to improve the performance of flexible laminated composites.

This study combines and twists 75D polyester (PET) multi-filaments and polylactic acid (PLA) multi-filaments with twist coefficients of 2, 3, 4, 5, and 6 to form 150D PET/PLA plied yarns. The 0.08-mm-diameter stainless steel (SS) fibers are made into SS braids with a 60-tooth braid gear and a take-up gear with 60, 70, 80, 90, or 100 teeth. PET/PLA plied yarn and SS braids are then combined and electrochemically treated with an electric current of 100, 200, 300, 400, or 500 mA at 60 °C for 24 hours, forming the PET/PLA/SS composite bone scaffolds. PET/PLA/SS composite bone scaffolds are observed by scanning electron microscope (SEM) and energy dispersive spectroscope (EDS), and tested for weight increase rate and biocompatibility. The experiment results show that the optimal twist coefficient for PET/PLA plied yarn is 4 and the optimal tooth number on the take-up gear for SS braids is 80. SEM observation result shows that hydroxyapatite (HA) deposits on the surface of PET/PLA/SS composite bone scaffolds and attaches to the PET/PLA plied yarns. Finally, regardless of electric currents, all PET/PLA/SS composite bone scaffolds possess good biocompatibility.

This study aims to investigate the mechanical properties, far-infrared (FIR) emissivity, and limiting oxygen index (LOI) of FIR ray/low-melting-point (LM) nonwoven fabrics, flame retardant (FR)/LM ...

This study proposes structural models of biodegradable vascular stents. One, two, or three plies of biodegradable polyvinyl alcohol (PVA) yarns are combined and twisted with twist factors of 2, 3, 4, 5, and 6 to form one-, two-, and three-ply PVA twisted yarns. The braided, warp-knitted, and weft-knitted PVA vascular stents are composed of PVA twisted yarns by using a braider, a warp knitting machine, and a weft knitting machine. The formation and mechanical properties of PVA vascular stents are evaluated, and the biological properties are examined in terms of biocompatibility through in vitro assay and subcutaneous embedding using in vivo assay. Test results indicate that the compression strength of PVA vascular stents is improved when using PVA twisted yarns containing a high number of plies and twist factor. Specifically, weft-knitted PVA vascular stents exhibit the optimal compression strength. PVA vascular stents treated with chemical cross-linking show weight loss lower than 3% after immersion in PBS solution for 30 days. Moreover, the antibacterial test and cell culture results suggest that PVA vascular stents are nontoxic and biocompatible. Subcutaneous embedding results show that PVA vascular stents retain intact formation when subcutaneously embedded in vivo for 28 days, indicating their good biological property. PVA vascular stents are suitable candidates for tissue engineering applications.

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.

This study aims to develop biodegradable vascular stents that prevent permanent damage caused by rejection of the immune system of the human body. Polyvinyl alcohol (PVA) yarns are twisted to enhance their strength. The twisted yarns are braided and then coated with chitosan (CS). The CS-coated PVA vascular stents are chemically crosslinked with genipin (GP) to improve their flexibility and biodegradability. Their morphological characteristics are also observed using a stereoscopic microscope, and their properties are evaluated through scanning electron microscopy, Fourier transform infrared, bending test, biodegradability test, drug release measurement, and MTT assay. Results reveal that wet PVA-CS-GP vascular stents coated with multiple CS layers can maintain a tubular structure when they are bent. After crosslinking is performed, the compressive strength of the PVA-CS-GP stents is 17.04 times higher than that of pure PVA. The weight loss rate of the PVA-CS-GP vascular stents as

Nonwoven fabrics were used as reinforcement to laminated composites to improve the mechanical properties and damage behaviors. The needle-punched Kevlar/LMPET nonwoven interlayer and two TPU covers were combined via thermal bonding to form the laminated composites. Tensile strength, peel load, and static puncture resistance of the laminated composites were evaluated in terms of needle punching rate and depth of the nonwoven interlayer. Results showed that tensile strength and static puncture resistance depended on the needle punching depth, primarily on the tangled fiber points. The peel load was dependent on the needle punching rate, especially on the resulting melted LMPET fibers. The laminated composites exhibited desirable tensile properties, peel load, and static puncture resistance.

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.

The polyester (PET) fibers and Kevlar® staple fibers, which are recycled from discarded selvages of PET and Kevlar® woven fabrics, are made into nonwoven fabrics using a needle-bonded process. The PET/Kevlar® nonwoven matrices are used as the surface layers, while a glass fiber woven fabric is used as the interlayer. The sandwich-structured composites are saturated with waterborne PU resin and then hot pressed, forming puncture resistant PU-reinforced PET/Kevlar® sandwiches. The sandwiches are evaluated in terms of the tensile property test, the bursting property test, the constant-rate puncture test, the dynamic puncture test, and the drop-weight impact test. The test results indicate that increasing the pick-up rate of PU resin can significantly improve all mechanical properties, suggesting that PU-reinforced PET/Kevlar® sandwiches have protective functions and make good candidate for insoles.

This study proposes using polypropylene grafted maleic anhydride (MA) to improve the interfacial compatibility between modified impact-resistant polypropylene (MPP) and thermoplastic polyurethane (TPU). The melt-compounding and injection method is used to prepare MPP/TPU/MA blends. The blending morphology, tensile behavior, flexural behavior, and impact behavior of blends are evaluated in terms of the content of TPU and MA. The SEM images show the positive influence of using MA on the compatibility between MPP and TPU, and only 1 wt% of it can efficiently decrease the difference in polarity and interfacial tension. As MA is an additional reinforcement, 100 wt% of the blends are made of MPP and TPU, indicating that more TPU means less MPP. When the blends are made of more TPU, the tensile strength of the control group (pure MPP/TPU blends) shows a decreasing trend. By contrast, MPP80/TPU20/MA3 blends have a tensile strength of 28 MPa and Young’s modulus of 927 MPa, while MPP90/TPU10/MA1 blends have the optimal flexural stress of 53.99 MPa and flexural modulus of 1493.61 MPa. Exception for MPP60/TPU40/MA1 blends, all the other experimental groups have greater impact strength as a result of using 1 wt% of MA. Specifically, MPP90/TPU10/MA1 blends have the maximum impact strength of 105.28 J/ m. The addition of MA has proven to efficiently improve the compatibility and interfacial adhesion between MPP and TPU, thereby forming an extraordinary bonding with a stabilized phase where a stress can be efficiently distributed. This study expects to design and adjust the performance of the composite blends according to the test results of SEM observation, tensile strength test, and impact strength test.

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.

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.

In this article, the new model of dynamic puncture behaviors of intra-/inter- reinforced compound fabrics which are fabricated by nonwovens and reinforced fabrics using needle-punching and thermal bonding technique is constructed by the maximum deformation and stress-wave transmission theory. Moreover, the number of layers for E1 puncture protection is optimized based on numerical analysis of penetration depth. Dynamic puncture model shows that the dynamic puncture resistance depends on elastic modulus of reinforced fabrics, deformation radius and thickness of compound fabrics. The maximum puncture resistance and penetration depth both have parabola relations to number of layers. This study provides the accurate prediction model of puncture force and safety layers for designing puncture-resisting body armor in the future.

This study aims to develop coronary artery stents using a spray-coating method. Chitosan is coated onto the polyvinyl alcohol (PVA) fibers in order to form PVA/CS coronary artery stents. The formation of chitosan is evaluated, examining the influences on the PVA/CS stents. The stents are evaluated using surface observation, scanning electron microscope (SEM) observation, thickness measurement, mesh size measurement, braid angle measurement, strut coverage rate measurement, compression strength test, and Fourier transforms infrared spectrometry (FTIR). The test results show that the spray-coating method successfully coats chitosan layer over the PVA/CS stents without sealing the mesh. Moreover, a longer spray coating span improves the compression resistance and maintains the perfect biocompatibility of the PVA/CS stents. This study successfully prepares PVA/CS coronary artery stents that are in a reticular, tubular manner, and coated with a well-formed chitosan layer.

This study uses 0.08mm copper wire and nickel-coated copper wire as the core and 75 D far infrared filament as the wrapped material to manufacture Cu/FIR-PET wrapped yarn, Ni-Cu/FIR-PET wrapped yarn and Ni-Cu/Cu/FIR-PET wrapped yarn. The three optimum metallic/FIR-PET wrapped yarns are then weaving into Cu/FIR-PET woven fabrics, Ni-Cu/FIR-PET woven fabrics and Ni-Cu/Cu/FIR-PET woven fabrics. Tensile property of metallic/FIR-PET wrapped yarns, electrical resistance of metallic/FIR-PET wrapped yarns, surface resistivity of metallic/FIR-PET woven fabrics and electromagnetic shielding effectiveness of metallic/FIR-PET woven fabric are discussed. According to the results, the optimum tenacity and elongation are chosen as 7 turns/ cm, electrical resistance of Ni-Cu/Cu/FIR-PET wrapped presents the best value, Cu/FIR-PET woven fabric has the lowest surface resistivity and Ni-Cu/Cu/FIR-PET woven fabric shows the best EMSE at 37.61 dB when the laminating-layer number is double layer and laminating at 90 ̊. In this study, three kinds of metallic/FIR-PET woven fabrics are successfully manufactured and looking forward to applying on industrial domains.

Logistics industry becomes the mainstream with promotion of life quality. The selection of delivery type and aging is subjected to limitations of packaging materials. In order to protect from product’s damage, this study purposes to use recycled high-strength fibers, including high-strength PET fiber, and Kevlar fibers, and thermal bonding PET fiber as well as glass fabric forming needle-punched 3D composite. For comparison of varying reinforcement on mechanical property, thermal bonding and water polyurethane impregnation are used to reinforce the 3D composite which is composed of nonwoven fabrics and glass fabrics. Result shows that, mechanical property from water polyurethane impregnation displayed much higher than that from thermal bonding. Thermal bonding remarkably improved burst strength and static puncture resistance. Therefore, 3D composite impregnated with water polyurethane reaches higher puncture protection level.

This study purposes to discuss effects of plied number and twist factor on polyvinyl alcohol (PVA) yarn and fabricate a degradable PVA vascular stent by the braiding process. PVA yarn was evaluated by stereoscopic microscope, tensile tenacity, tensile elongation, twist angle, force and elongation efficiency. Research result shows that yarn after plying and twisting effectively improves the mechanical strength by stereoscopic microscopic observation. After PVA yarn was made into stent by braiding technique, stent presents the network and tubular structure. This study verifies that the mechanical property of PVA yarn can be improved via plying and twisting process, and PVA yarn can be successfully made into vascular stent.

Thermoplastic polyurethane (TPU) honeycomb grid can be served as a buffering packaging material due to its special construction. Using its structure property, structure body produces dynamic stress and strain when suffering from stress. One part of energy is stored, and other part is converted into heat dissipated by structure conduction, thus TPU honeycomb grid is a kind of viscoelastic materials with high compression. Therefore, this study designs to fabricate the buffering composite nonwoven with three-dimensional (3-D) honeycomb sandwiched structure using 3-D crimped PET inflame-retarding fibers and TPU honeycomb grid through nonwoven processing technique. In the processing, areal weight of PET inflame-retarding nonwoven compounded with TPU honeycomb grid was changed. By measurements of tensile strength, strength efficiency, tensile elongation and tear strength, effects of processing parameters on mechanical property of composite nonwovens were discussed. Testing result shows that TPU honeycomb grid buffering composite nonwoven has better tensile strength even with change of areal weight for PET nonwoven. When PET nonwoven is 250 g/m2, tensile strength along CD and MD is 285.6 N and 284.2 N respectively.

This study prepared a far-infrared composite wire using a new preparation technology. The stainless steel fiber/polyester fiber double-layer wrapped yarn was used as core material, and then polypropylene masterbatch which has far-infrared powder was coated on the core material forming far-infrared composite wire. The properties of far-infrared composite wire were evaluated by tensile test and surface observation. Composite wires were woven into woven fabrics. And the air permeability and far-infrared emissivity of composite fabrics were also evaluated. Result shows that, the coating technique reinforces the strength of composite wire insignificantly, but it gives the fabric with far-infrared function.