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This study employs the solution mixing method to produce composite films by using polyvinyl alcohol (PVA), graphene nano-sheets (GNs), and multi-walled carbon nanotubes (MWCNTs). Tensile test, differential scanning calorimetry (DSC), four-point probe/coaxial transmission line method are performed in order to evaluate the tensile properties, melting and crystallization behaviors, electric conductivity, and electromagnetic interference shielding effectiveness (EMI SE) of the composite films. The test results indicate that with the increasing amount of MWCNTs, GNs/MWCNTs hybrid fillers cause a synergy effect that contributes to the tensile strength of the composite films. An optimal GNs/ MWCNTs ratio is 0.5 wt%:1wt% that provides the films with a tensile property of 19.6 MPa, an improvement on glass transition temperature (Tg), melting temperature (Tm) and crystallization temperature (Tc) of PVA, an electric conductivity of 2.6×10-5 S/cm, and EMI SE of -15 dB at frequency 1 GHz-2 GHz that is equal to a 99.9 % shielding level required by livelihood necessities.

This research focuses on making double-layer complex wrapped yarn using stainless steel fiber (S), rayon yarn, and PET bamboo charcoal yarn in rotor twister. During the process, the twisting speed of the rotor twister was changed. The functional complex thermal-regulating/wicking conductive wrapped yarn of different twisting speeds (2~6 turns/cm) were fabricated using the Fully Computerized Hosiery Machine. The effects of different twisting speeds on the far-infrared emissivity, air permeability, and water absorption of the functional complex thermal-regulating/wicking conductive wrapped yarn were discussed. In the end, the functional knitted fabrics and hosiery with thermal-regulating/wicking conductive properties were made.

In this study, different combinations of non-woven fabric, glass fiber fabrics, and carbon fiber woven fabrics are needle punched, and are then laminated with 3D fabrics. These materials are impregnated in a two-package PU blowing agent in order to form 3D fabric/PU foam composites. Bursting strength test, compression test, dart drop test, and sound absorption test are used to evaluate the effect of the skin fabrics on the properties of 3D/PU foam composites. The test results suggest that the skin fabrics containing nonwoven fabrics and carbon fiber woven fabrics have an optimal bursting strength of 4320.9 N. The skin fabrics that are composed of nonwoven fabrics and glass fiber woven fabrics have an optimal compressive strength of 15 MPa. The drop-weight impact test results indicate that skin fabric containing nonwoven fabrics and glass fiber woven fabrics have a residual stress of 540.8 N, moreover, this skin fabric also attain an optimal sound absorption coefficient of 0.9. Therefore, having composite fabrics as the skin layer is conducive for the mechanical properties and sound absorption coefficient of PU foam materials. In addition, the proposed 3D/PU foam composites can be mechanically reinforced, and the disadvantages of their constituent 3D fabrics can also be improved. The skin composite fabrics are adjustable for possible clinical applications, and provide the 3D/PU foam composites with diversity of applications, such as building materials and protective materials.

Electrically conductive stainless steel wire and synthetic polyester filament are selected as the materials for this study. Composite wrapped yarns and composite woven fabrics are successfully manufactured by* wrapping and weaving processes. The breaking strength, tenacity, elongation and work of composite wrapped yarns exhibit the optimum value at 7-D, 7-S, 14-S and 14-D, which the corresponding value are 149.3(N), 1.6(cN/dtex), 19.5(%) and 46.7(N*cm), respectively. The surface resistivity of 4 composite woven fabrics presents similar results with various weft yarns that are composed of various wrapped counts and wrapped layers. Electromagnetic shielding effectiveness (EMSE) of composite woven fabric, which varied laminated angles and laminated numbers, significantly reveal different results. The EMSE of composite woven fabrics is considerably enhanced after varying laminated angles of 45° or 90° and laminated numbers, and that of composite woven fabric (14-D-W) with a laminated angle of 90°and a laminated number 3 shows the optimum value -46 dB at 2450 MHz.

This study aims to produce antimicrobial biodegradable composite films. Polylactic acid (PLA) and poly[2-(tert-butylaminoethyl)methacrylate] (TBMA) are combined by using casting molding. The Fourier transform infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC) are used to evaluate the physical properties of the PLA/TBMA composite films. The antimicrobial tests are then used to assess the antibacterial efficacy of PLA/TBMA composite films against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). The FT-IR results indicate that the incorporation of TBMA does not influence the chemical structure of the composite films as the composites are a product of physical blending. The DSC results indicate that the incorporation of TBMA causes the crystallization temperature of PLA to increase. Finally, the composite films have proven to be bacteriostatic against S. aureus, and antibacterial against E. coli.

In this study, polylactic acid (PLA) and Triclosan with blending ratios 99:1, 97:3, and 95:5 wt% are dissolved in Dichloromethane via the solution method. The mixtures are then made into PLA/Triclosan composite films by using a casting method. The tensile strength test and differential scanning calorimetry (DSC) are used in order to evaluate the mechanical properties and thermal behaviors of composite films. Finally, Escherichia coli (E. coli) and Staphylococcus auresus (S.aureus) are used to culture with the composite films in order to examine the optimal antimicrobial efficacy of different PLA/Triclosan composite films. The test results indicate that the composite films have a slightly lower tensile strength when the films are composed of 5wt% of Triclosan. Increasing Triclosan contents decreases the Tg of the composite films according to DSC results. Moreover, the antimicrobial efficacy of composite films increases with the increasing Triclosan content, and the antimicrobial efficacy against S.aureus is higher than E. coli.

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.

Highly resilient polyester (HRPET) fibers and low-melting-point polyester (LPET) fibers are made to form into protective nonwoven fabrics. The influences of different parameters on the mechanical properties of the nonwoven fabrics are evaluated in terms of falling weight tests, bursting strength testing, tear tests, and tensile tests. The test results indicate that the maximum strengths occurs with an optimal HRPET/LPET blending ratio of 8:2: tensile strength (602 N), bursting strength (477 N), and resiliency (40 cm).

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 formulates polyvinyl alcohol (PVA) solution and Bletilla striata (BS) extractive with various mixing ratios into various mixtures, which are then electrospun into composite membrane with settings of a specified voltage of 12 kV, collection distances of 12 cm, PVA concentrations of 12 wt%, and BS additions of 0.1, 0.3, and 0.5 %. The various PVA/BS mixtures are tested for conductivity and viscosity, and the resulting electrospinning composite membranes are evaluated with surface morphology analysis, Fourier transform infrared spectra (FT-IR), and diameter analysis. The test results show that the content of BS is proportional to the conductivity of the mixtures. The addition of *BS decreases the diameter of the electrospinning fibers, while also creating beads on the fibers. The diameter of the electrospinning fibers increases as a result of the increasing concentration of PVA solution or the increasing collection distance. The FT-IR results indicate the absent chemical reaction between PVA and BS.

This study blended recycled Kevlar fibers and PP fibers with 70:30 wt%:wt% and fabricated Kevlar/PP composite nonwoven using needle punching and hot processing processes. The hot pressing temperature was set as 160, 170 and 180℃, and un-hot-pressed composite nonwoven was considered as the control group. Kevlar fibers played as the reinforcing fibers. The tensile, tear, burst and constant-rate static puncture properties of composite nonwovens hot-pressed at different temperature were discussed. Result shows that, 170℃ hot pressing temperature exhibited the better mechanical performance and thus considered as the optimum processing condition.

The combination of functional electrical products improves the value of textiles, including measurement, detection, and communication. These added values, however, have a negative influence on comfort and consumer acceptance. This study proposes using a knitting technique and conceals the circuit that connects electrical components inside the textiles, thereby ensuring satisfactory comfort and mechanical properties. The pattern designed using a crochet machine is applied to the preparation of conductive elastic knits. During the process, different numbers and types of conductive yarns are incorporated. The stiffness, tensile strength, elastic response rate, air permeability, and electrical resistance of conductive elastic knits are evaluated. The rigidity and electrical resistance test results show that increasing the numbers of conductive yarns results in a lower electrical resistance, as well as a rugged knit surface and exposure of the yarns. Moreover, increasing the numbers of conductive yarns does not pertain to the physical properties of elastic knits, according to the results of air permeability, tensile strength, and elastic recovery tests.

Hydrogels have been used in related biomedical fields, and their pore size and structure are an important investigation emphasis in relative studies. Hydrogels with different pore sizes have different applications. This study aims to examine the pore size and porosity of the polyvinyl alcohol (PVA) tubular hydrogels. Sodium chloride (NaCl) with different concentrations serves as the porogen while polyvinylpyrrolidone (PVP) serves as the surfactant. PVA is made into tubular hydrogels via a freeze-thaw method and the cross-linking with glutaraldehyde. The hydrogels are then processed with an ultrasonic vibration in order to remove the residual solvents and the porogens, in order to obtain tubular PVA hydrogels with an interconnected porous structure. The test results indicate that the porosity and pore size of the PVA hydrogels significantly increase as a result of the uses of a porogen. Excessive NaCl as a porogen damages the porous structure of hydrogels, which in turn decreases the porosity and pore size of the hydrogels.

Regular nonwoven sound absorbing materials are short of flame retardant properties, and this study aims to produce nonwoven fabrics with sound absorption and flame resistance. Flame retardant polyester (PET) fibers are made into matrices. These matrices are combined with low melting point polyester (LPET) fibers via needle punching in order to form sound-absorbing/flame-retarding composite nonwoven fabrics. The tensile strength, bursting strength, sound absorption, and limited oxygen index (LOI) measurements are then used to evaluate the composite nonwoven fabrics, thereby examining the optimal parameters. Using an LPET matrix as the interlay and being hot pressed, the composite nonwoven fabrics have the maximum sound absorption due to the interior pore structure is improved.

This study aims at producing three-dimensional porous polylactic acid (PLA) bone scaffolds using a web manufacturing. Webs are laminated and are then processed with heat treatment in order to form low *melting point PLA porous bone scaffolds. A stereomicroscope, a scanning electron microscope, the pore size measurement, porosity, and compression test are used in order to evaluate the bone scaffolds. The test results indicate that regardless of the temperatures of heat treatment, all PLA porous bone scaffolds have interconnected pores. An increasing temperature of treatment causes the pore size to decrease from 160μm to 100μm and mechanically improves the bond scaffolds. Therefore, this study successfully creates porous bone scaffolds made of low melting point point PLA and web lamination techniques.

With the rapid growth of various economic, peoples have proposed higher demand for living quality. Of the common pollution in daily life, noise pollution makes people tired, and thus commonly affects spirit concentration and working efficiency. Sound absorbing decoration scarcely has flame retarding. As the increasing demand for safety, ignition, flame spread rate and combustion visibility and smog toxicity correlate with the escape chance for people. This study prepares nonwoven using low-melting PET fibers and inflame-retarding PET fibers, and then thermally bonded it after inter-lamination, anticipating to with inflame-retarding via inflame-retarding PET and to with sound absorption via lamination and hot baking as well as to with mechanical properties including tensile, burst and static puncture. Result shows that hot baking for 15 min makes the composite nonwoven along MD the highest strength, but un-hot-baking composite nonwoven has the excellent performance at burst and sound absorbing properties. Hot baking time not significantly affects LOI performance, but all samples reach the standard of fire retardant.

Climate change causes diverse disasters, such as landslides and debris flow, and civil engineering thus becomes a common strategy for prevention and remedy. Geotextiles are textiles that are made of polymer materials, and have a variety of functions. One common function of geotextiles is reinforcement that uses their mechanical properties to defend the externally exerted force or secure soils. Geotextiles have a large range of applications and for example are used as reinforcement in dikes, hillsides, and foundations. Additionally, geotextiles can be formed into different structures to meet the requirements of the environment. In this study, the recycled Kevlar selvages are combined with polyester (PET) and polypropylene (PP) fibers in order to form nonwoven geotextiles. The otpimal amount of Kevlar fibers is examined. PET cont. filaments are then laminated on the geotextiles that are made with optimal Kevlar amount, and then needle punched. The properties of the product are evaluated. The test results suggest that the addition of either Kevlar fibers or PET cont. filaments results in improvement in the mechanical properties of the geotextiles.

Nanofibers have a high specific surface area and a high porosity, and thus have been applied to many fields. Electrostatic spinning is one efficient and convenient method for the preparation of nanofibers. Two influential factors of the formation of nanofibers include processing parameters, such as voltages and velocity, and environmental factors, such as temperatures and humidity. This study uses a home-made electrospinning machine for the production. The morphology of the resulted nanofibers is examined in terms of the processing parameters, in order to provide f more feasible applications. The test results indicate that the viscosity of PVA electrospinning solution becomes dense as a result of the increasing temperatures. An increasing voltage changes the morphology of nanofibers from being smooth to rugged. Moreover, the diameter of nanofibers becomes smaller when the electrospinning distance is increased. *

Interim dentures are easily broken on the bridge, and this cause has a negative effect on the dentures. This study aims to evaluate the impact strength and flexural strength of dentures in relation to two fiber blending ratios, in order to examine the negative influences of the addition of fibers to acrylic resin on the properties of interim dentures. The powder and solvent are blended at a ratio of 1:1. Different amounts of glass fibers or modified glass (M-glass) fibers are respectively added to the mixtures. These mixtures are well stirred and are processed for molding in order to make different composites. The composites are evaluated for impact and flexural strengths. The test results indicate that the composites containing 0.6 % glass fibers exhibit optimal aesthetic appearance and maximum mechanical strengths. The resulting resin composites can be applied to crowns, bridges, and tooth bases.

The majority of commercially available mosquito repellents contains N, N-diethyl-3-methylbenzamide compound (DETT). The long term uses of DETT have a negative influence on the nervous and *immune systems. Therefore, the development of mosquito repellents that are DETT-free is important. In this study, essential oils of lavandula angustifolia, Melaleuca Alternifolia, Mentha piperita, Eucalyptus globules, and Eucalyptus citriodora are evaluated in terms of the repellent efficacy against F. taiwana by using a Y-tube olfactometer test. Their repellent efficacy is then compared. The combination of 200 μl lavandula angustifolia and Eucalyptus citriodora attains a repellent efficacy of 70% and 65%, respectively. Conversely, using Melaleuca Alternifolia, Mentha piperita, and Eucalyptus globules does not result in any significant repellence against F. taiwana, which may be ascribed to the high concentration. When 1μl of these essential oils are added, they have a repellent efficacy of 61-65%. The repellent efficacy of different essential oils is ranked as Eucalyptus globules>Mentha piperita = Melaleuca Alternifolia> lavandula angustifolia> Eucalyptus citriodora.

This study proposes making polyethylene oxide (PEO) and water-soluble chitosan (WSC) nanofiber membranes via electrospinning. PEO/WSC mixtures are evaluated in terms of viscosity and conductivity, and are then electrospun into PEO/WSC nanofiber membranes using different voltages. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) are performed to examine the structure of the nanofiber membranes. The test results indicate that a combination of a voltage of 20kV and a PEO/WSC ratio of 70:30 can form complete electrospun nanofibers. In addition, increasing the viscosity of the PEO/WSC mixtures can decrease the amounts of beads in the nanofibers.

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.