Showing papers in "Textile Research Journal in 2014"

Auxetic materials and their potential applications in textiles

Abstract: Auxetic materials are a kind of non-conventional materials having negative Poisson’s ratio. They laterally expand when stretched or laterally shrink when compressed. Compared to conventional materials, auxetic materials have a number of enhanced properties that could be very interesting for some special applications. This paper reviews the latest achievements in auxetic materials, including their properties, structures and applications. A special discussion on their potential applications in textiles is also made. It is expected that this review could provide some useful information for the future development of auxetic textile materials.

Cellulose polymorphs and physical properties of cotton fabrics processed with commercial textile mills for mercerization and liquid ammonia treatments

Abstract: We report the detection of cellulose polymorphs, using spectroscopic and diffraction techniques, in cotton fabrics treated with commercial textile mill processes designed for better dyeing and mechanical properties. Vibrational sum frequency generation (SFG) spectroscopy analysis of cotton is known to be selective and sensitive to the crystalline cellulose portion in the sample. The SFG analysis results were compared with the results from conventional analytical techniques such as X-ray diffraction (XRD) and infrared (IR) spectroscopy. The XRD detection of a small fraction of cellulose II present in the partially-mercerized fabric was difficult, while SFG and IR analysis indicated the partial conversion of cellulose I to II without significant reduction of the cellulose crystallinity. Processing the cotton fabric with the liquid-ammonia treatment mill caused partial conversion of cellulose I to III and significant reduction of the overall crystallinity of cellulose. All XRD, SFG, and IR techniques were ab...

Electromagnetic shielding properties of woven fabrics made from high-performance fibers

Abstract: The expansion of the electronic industry and the extensive use of electronic equipment in communications, computations, automations, biomedicine, space, and other purposes have led to problems such...

The effects of surface energy and roughness on the hydrophobicity of woven fabrics

Abstract: The wetting behavior of a hydrophobic rough surface is investigated on a surface fabricated by applying low surface tension materials such as silicone or fluoropolymer to polyester woven fabric consisting of multifilament yarns. The roughness factor of various woven fabrics can be calculated by Wenzel’s and Cassie–Baxter’s equations. For the fabrics treated with silicone or fluoropolymer, the Cassie–Baxter model was applied, showing a level of agreement for the fabric specimens non-textured filament fibers between the predicted contact angles and the measured values. More precisely, the fabrics treated with silicone or fluoropolymer represent the transitional state between the Wenzel type and the Cassie–Baxter type; that is, the fractional contact area between the water and air f2 is greater than zero, and the sum of the fractional contact areas for solid–water f1 and air–water f2 is greater than 1. A surface with lower energy and higher roughness gave f1 + f2 close to 1 with smaller f1 and larger f2, whi...

Protective properties of warp-knitted spacer fabrics under impact in hemispherical form. Part I: Impact behavior analysis of a typical spacer fabric

Abstract: This paper presents an experimental study of the protective properties of warp-knitted spacer fabrics developed for protecting the human body on impact. A drop-weight impact tester was used to test the fabrics in a hemispherical form to simulate the use of impact protectors in real life. The study consists of two parts. The first part, presented in the current paper, focuses on the impact behavior of a typical spacer fabric impacted at different levels of energy. The analysis includes the impact process and the energy absorption and force attenuation properties of the spacer fabric. Frequency domain analysis is also used, to identify the different deformation and damage modes of the fabric under various levels of impact energy. The results show that the impact behavior of the fabric under impact in the hemispherical form is different from that in the planar form. The results also indicate that the curvature of the fabric can reduce energy absorption during the impact process and therefore reduce the force attenuation properties of the spacer fabric. This study provides a better understanding of the protective properties of spacer fabrics. The effect of fabric structural parameters and lamination on the protective properties of spacer fabrics under impact will be presented in Part II.

Cut resistance and failure of high-performance single fibers:

Abstract: The cut resistance of organic and inorganic high-performance single fibers has been studied. Several fiber types were examined, including Kevlar, Twaron, Vectran, Technora, Zylon, Dyneema, carbon f...

A review: effect of conductive polymers on the conductivities of electrospun mats:

Abstract: The effects of conductive polymers on conductivities and morphologies of electrospun fabrics are analyzed. The factors that affect the conductivities and morphologies are discussed. Some applications of these conductive nanofibers are reported. The introduction of conductive polymers into nanofiber mats has the potential to provide sufficient conductivity for many applications. An improved conductivity can be achieved by maximizing the content of conjugated polymers. The selection of conductive and carrier polymers, solvents, doping agents, oxidizing agents and ratios of them are also important to obtain sufficient properties. Carbon fiber, carbon black and carbon nanotubes are not covered in this review.

Antimicrobial and antioxidant functionalization of viscose fabric using chitosan–curcumin formulations

Abstract: The purpose of this work was to develop new additive combinations between chitosan and curcumin in solutions as a fiber-coating. Diverse additive combinations between chitosan and curcumin in solutions were adsorbed onto viscose fabrics in order to reach the essential antimicrobial and antioxidant functionalization for medical textiles. The goal of this paper was to examine the adsorption of these two compounds as an additive formulation on viscose textile material as well as to analyze the desorptions of both substances from the fabric surface. Finally, the antimicrobial and antioxidant properties of viscose fabrics functionalized by chitosan–curcumin formulations were respectively examined. Curcumin as an adsorbate for textiles in combination with chitosan represents an added-value because of its anti-oxidative properties, and showing the potential to enhance existing antimicrobial performance of chitosan when applied using the preferred procedure.

Deformation behaviors of three-dimensional auxetic spacer fabrics:

Abstract: Auxetic spacer fabrics are a novel kind of three-dimensional (3D) fabric structure with a negative Poisson’s ratio. They have found a number of applications in functional garments, protective pads and sportive shoes due to their unusual properties. In this paper, a study on deformation behaviors of 3D spacer fabrics that could be fabricated on a large scale is reported. Through experimental observations of deformation of a basic hexagonal unit at different tensile strains, two different geometrical models are proposed for the fabric structure when extended in the course direction and wale direction, respectively. Based on the geometrical models, two semi-empirical equations between the Poisson’s ratio and tensile strain are established for both tensile directions. The study shows that the established semi-empirical equations fit well with experimental results. Therefore, they could be used in the design and prediction of 3D auxetic spacer fabrics with different values of geometrical parameters.

Textile touch sensors for wearable and ubiquitous interfaces

Abstract: The design of textile touch sensing interaction was explored with the new metal composite embroidery yarns (MCEYs) and a simple and easy fabrication technique aimed towards robust and reliable pres...

ZnO-modified hybrid polymers as an antibacterial finish for textiles

Abstract: The antibacterial activity of ZnO is reported by several authors. We present the preparation and application of inorganic–organic hybrid polymers modified/filled with ZnO nanoparticles of varying p...

Protective properties of warp-knitted spacer fabrics under impact in hemispherical form. Part II: effects of structural parameters and lamination:

Abstract: This part aims to investigate the effects of structural parameters and lamination on the impact force attenuation properties of warp-knitted spacer fabrics developed for impact protectors. A series...

Electro-mechanical properties of knitted wearable sensors: Part 2 – Parametric study and experimental verification:

Abstract: An optimization design simulating the electro-mechanical property of the conductive elastic knitted fabric is built based on a loops structure under biaxial extensions. A computer program can give ...

Discharge characteristics of poly(3,4-ethylene dioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) textile batteries; comparison of silver coated yarn electrode devices and pure stainless steel filament yarn electrode devices

Abstract: This paper investigates textile-based energy storage devices fabricated with poly(3,4-ethylene dioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) as an electro-active polymer and conductive yarns as the electrodes. The conductive yarns are sewn into a textile substrate and then coated with PEDOT:PSS systematically. Two different sets of devices were made. A comparison of the devices made with silver coated polybenzoxazol filament yarns and the devices made with pure stainless steel filament yarns is performed. The devices were charged and their self-discharge was measured by voltage decay. A study of the influence of charging time on the decay and the effect brought by various load resistors on the voltage decay is also performed. In this research, the devices with electrodes of pure stainless steel filaments yarns performed better than the devices with silver coated yarns; this outcome has been reported as standard by various researchers.

Cellulose–PEG grafts from cotton waste in thermo-regulating textiles

Abstract: This study focused on the production of heat storage materials from cotton wastes by incorporating a phase-change material and determination of their thermo-regulating properties. Polyethylene glyc...

Improved accuracy in the determination of flexural rigidity of textile fabrics by the Peirce cantilever test (ASTM D1388)

Abstract: Within the field of composite manufacturing simulations, it is well known that the bending behavior of fabrics and prepregs has a significant influence on the drapeability and final geometry of a composite part. Due to sliding between reinforcements within a fabric, the bending properties cannot be determined from in-plane properties and a separate test is required. The Peirce cantilever test represents a popular way of determining the flexural rigidity for these materials, and is the preferred method in the ASTM D1388 standard. This work illustrates the severe inaccuracies (up to 72% error) in the current ASTM D1388 standard as well as the original formulation by Peirce, caused by ignoring higher-order effects. A modified approach accounting for higher-order effects and yielding significantly improved accuracy is presented. The method is validated using finite element simulations and experimental testing. Since no independent tests other than the ASTM D1388 standard are available to determine the bending stiffness of fabric materials, experimental validation is performed on an isotropic, homogeneous Upilex-50S foil for which the flexural rigidity and tensile stiffness are related. The flexural rigidity and elastic modulus are determined through both the cantilever test (ASTM D1388) and tensile testing. The results show that the proposed method measures an elastic modulus close to that determined through tensile testing (within 1%), while both the Peirce formulation (+18%) and ASTM standard (+72%) over-estimate the elastic modulus. The proposed methodology allows for a more accurate determination of flexural rigidity, and enables the more accurate simulation of composite forming processes.

Flame retardant polyamide 6/nanoclay/intumescent nanocomposite fibers through electrospinning:

Abstract: Flame retardant polyamide 6 (nylon 6) nanocomposite nanofibers containing montmorillonite clay (MMT) platelets and intumescent non-halogenated flame retardant (FR) additives were processed by elect...

Effects of multiple air gaps on the thermal performance of firefighter protective clothing under low-level heat exposure:

Abstract: The thermal performance of firefighters' protective clothing entrapping multiple air gaps and exposed to low heat fluxes has been studied using a newly designed bench-scale test apparatus. Differen...

Comparison of electromagnetic shielding effectiveness of conductive single jersey fabrics with coaxial transmission line and free space measurement techniques

Abstract: The aim of this study is to investigate the electromagnetic shielding effectiveness (EMSE) of thin and lightweight knitted fabrics that are suitable for casual wear like t-shirts. For the purpose o...

Stretch sensing properties of conductive knitted structures of PEDOT-coated viscose and polyester yarns

Abstract: Wearable textile-based stretch sensors for health-care monitoring allow physiological and medical evaluation without interfering in the daily routine of the patient In our previous work, we succes

Fabrication and evaluation of a notched polymer optical fiber fabric strain sensor and its application in human respiration monitoring

Abstract: This paper describes an intensity-based notched polymer optical fiber (POF) fabric strain sensor and its application in human respiration monitoring. A mechanical analysis illustrates geometrical profiles of constrained fiber loops on the fabric substrate. V-shaped notches are made by laser ablation on the sides of the POFs. The effects of loop parameters and processing conditions on the sensing performance are investigated. The experimental results show that the fabric sensor is more sensitive to strain with notches on the outer side of the loops, a small radius of the loops and a low scanning speed of laser. This fabric sensor exhibits a large measurable strain range of up to 21%. The achieved strain sensitivity is 3.77. The temperature and relative humidity have little effect on strain sensitivity between 0℃ and 60℃. A belt has been fabricated by integrating the fabric sensor for monitoring human respiration. The evaluation trials show a strong correlation between the belt system and a clinic monitor.

Monitoring of acoustic emission damage during tensile loading of 3D woven carbon/epoxy composites:

Abstract: Registration of acoustic emission (AE) events during tensile loading of fiber-reinforced composites allows the damage caused by these events to be defined and monitored, including damage initiation...

Electromagnetic shielding effectiveness of polyester fabrics with polyaniline deposition

Abstract: In this study, conductive fabrics were developed by polymerizing aniline onto polyester (PET) woven fabrics. The fabric treatment was carried out by the chemical polymerization method at 0.5 M, 0.8...

Suitability of knitted fabrics as elongation sensors subject to structure, stitch dimension and elongation direction

Abstract: The area of smart textiles has recently attracted more and more attention. One of the challenges in this domain is the development of textile sensors, such as textile electrodes, pressure sensors, ...

The effect of wind, body movement and garment adjustments on the effective thermal resistance of clothing with low and high air permeability insulation:

Abstract: Using a thermal manikin, the total clothing thermal resistance (IT) of two clothing ensembles with the same air-impermeable outer layer but with either high or low air permeability insulation was d...

Dielectric and morphological studies of nanostructured polypyrrole-coated cotton fabrics

Abstract: In this study, nanostructured polypyrrole (PPy)-coated cotton textiles were produced by in situ chemical oxidative polymerization and dielectric/electrical properties of PPy-coated cotton fabrics w...

Electromechanical properties of knitted wearable sensors: part 1 – theory

Abstract: This paper reports the development of a hexagon resistance model, based on the loop structure of a plain weft knitted fabric. This model is capable of describing the electromechanical properties of conductive knitted elastic fabrics. Based on the relationship between the resistance and the load on the fabric under biaxial extension, the equivalent resistance of the fabric was obtained by solving the circuit network equations. It was found that the circuit network is a multiple circuit parallel to the wale direction whereas it is in series along the course direction. And Holm’s electrical contact theory is used to calculate the relationship between the contact resistance and the contact force in an elastic fabric sensor. The contact load and deformation between two knitting loops are calculated using the classical knitted fabric mechanics model of Kawabata and Popper.

Experimental investigation the dynamic pressure attenuation of elastic fabric for compression garment

Abstract: Compression garments are made of elastic fabric, which is used for operational reasons and clinical applications for treating venous ulceration, deep vein thrombosis or burns. The constant pressure...

Fabric defect detection via small scale over-complete basis set:

Abstract: Defect detection has been a focal point in fabric inspection research and remains challenging. In this paper, a novel method for fabric defect detection is presented. In the proposed algorithm, only defect-free fabric images are used to build the over-complete basis set via sparse coding. Compared to traditional defect detection methods via sparse coding, our method uses a Gabor filter to reduce the complexity of the fabric signal, and takes the fabric patch’s projections in the small scale over-complete basis set as the original features, not the sparse representation. We compare the averages of the patch and its neighborhoods’ features with the standard features, which are the averages of all defect-free fabric images’ features. At last, according to this compared distance, the patch is classified as defective or non-defective. The experimental results on our own database and the TILDA database reveal that our features are more robust and the proposed algorithm can detect defects on twill, plain, gingha...

Surface modification of aramid fibers by atmospheric pressure plasma-enhanced vapor deposition

Abstract: Recent research results have indicated positive influences of inter-yarn friction on ballistic performance of woven fabrics and panels made from such fibers. The current investigation explores the effect of coating by means of atmospheric pressure plasma-enhanced vapor deposition with organic chemical (CH3)2Cl2Si on the inter-yarn friction. The scanning electron microscopy observations indicated that as the treatment time increases, more particles have been deposited on the surface of the fibers. The Fourier transform infrared spectra supported the existence of Si-O-Si vibration, which can be attributed to the chemical deposition. Energy-dispersive X-ray analysis further supported the deposition of the chemical compound. Experiments were carried out to evaluate the coefficients of static and kinetic frictions between the yarns and the results showed that the inter-yarn coefficient of static friction was increased from 0.1617 to 0.2969 and that of the kinetic friction increased from 0.1554 to 0.2436, as the treatment time increased to 4 minutes. In addition, there is evidence that the mechanical properties of the treated yarns were not negatively affected by the treatment.