bluuebunny/crossref_metadata_2025 huggingface dataset:
Dissipation of Triboelectric Charge into Air from Textile Surfaces
Authors: Onogi Yoshihiko , Sugiura Naoko , Nakaoka Yasue
Published: March 2008

Triboelectric charges on textile fabrics are thought to dissipate mainly by conduction by means of free electron diffusion. Charges on the surface of fabrics disappear by other processes, however, such as neutralization with counter ions and scattering into the air. In this study, water molecules on the textile surface play an important role in the charge scattering into air, i.e., electric charge carried away by water molecules when they evaporate. Two kinds of water molecules exist on the textile surface—one not related to charge dissipation and one carrying the electronic charge away from the fabric surface.
Quantitative Analysis of the Nonformaldehyde Durable Press Finish on Cotton Fabric: Acid-Base Titration and Infrared Spectroscopy
Authors: Yang Charles Q. , Bakshi Gagan D.
Published: March 2008

Butanetetracarboxylic acid (BTCA) has been a promising nonformaldehyde durable press finish for cotton fabrics to replace N-methyol reagents. Acid-base titration and Fourier transform infrared (FT-IR) spectroscopy are applied as quantitative analytical techniques to determine the amount of BTCA applied to cotton fabric and the amount of ester formed on the fabric after a curing process. Acid-base equilibria of BTCA are discussed. We find that FT-IR spectroscopy is a reliable quantitative analytical technique for quantifying BTCA and its ester on cotton fabric when the calibration standards are established by acid-base titration. Calibration curves and regression equations are pre sented. To determine the amount of ester formed on the finished cotton fabric using FT-IR spectroscopy, it is necessary to use a sodium hydroxide solution to quantitatively convert carboxyl to carboxylate. The acid-base equilibria associated with this procedure are also discussed.
Formation of Neps in Air-Jet Texturing Using a Central Composite Design
Authors: Kothari V.K. , Sengupta A.K. , Sensarma J.K.
Published: March 2008

Nep formation, a drawback in the air-jet texturing process, can be controlled to some extent by suitable choices of certain factors related to the process. In order to understand how these variables influence nep formation in air-jet texturing, a central composite design is formulated and four variables—air pressure, texturing speed, me chanical stretch, and overfeed—are considered. Analysis of the results indicates that air pressure, texturing speed, and overfeed contribute significantly to nep formation, but mechanical stretch has little or no effect.
Biological Variation in the Degree of Polymerization of Cotton Lint Cellulose Produced in South Africa
Authors: Schneider Marlene , Swart Jan P.J. , Sanderson Ron D.
Published: March 2008

Size-exclusion chromatography coupled with a multi-angle laser light-scattering de tector is a proven and effective technique for measuring absolute molecular weights ( Mw) and molecular weight distributions of cellulose derivatives. Because cellulose is a natural polymer with much variation, average Mw and degree of polymerization (DP) values are of limited value. By plotting and processing absolute DP distributions as directly calculated from the Mw values, an accurate estimate of the DP distribution of a cellulose sample can be obtained. This approach offers the possibility to extend current data processing, which consists mainly of graphic presentations, to exhaustive statistical analyses of the acquired data, previously not possible.
Biological Variation in the Degree of Polymerization of Cotton Lint Cellulose Produced in South Africa
Authors: Schneider Marlene , Swart Jan P.J. , Sanderson Ron D.
Published: March 2008

The SEC-MALLS techniques, together with an alternative method for data treatment, are used to determine actual DP distributions of the cellulose of southern African Acala 1517/70 cotton lint. This alternative approach offers the possibility of exhaustive statistical analyses of acquired data, previously not possible. The results of these analyses show the influence of production area and year on variations in DP distributions of the cellulose of South African cotton lint.
Diffusion of p-Aminoazobenzene into Laminates of Film and Fabric
Authors: Sasaki H. , Morikawa H.
Published: March 2008

We have investigated the concentration distribution of p-aminoazobenzene in lam inate slabs of fabric and film. Because the diffusional boundary layer exists on multiple layers of fabric, a ternary laminate slabs model is used to describe diffusion behavior. Heterogeneity at the phase interface makes it necessary to modify the partition coef ficient between fabric and film, so that a fit can be obtained between the observed and calculated curves.
Automatic Inspection of Fabric Defects Using an Artificial Neural Network Technique
Authors: Tsai I-Shou , Hu Ming-Chuan
Published: March 2008

Artificial neural networks (ANN), with capabilities of fault tolerance and learning, can be used to detect fabric defects. Because the back propagation algorithm, has higher learning accuracy and successful applications, we have used it in this study to identify missing ends, missing picks, oily fabric, and broken fabric, all often found as defects in fabrics. The correct selection of characteristic parameters for the input layer in an ANN plays a great role in the recognition rate. The spatial periodicity of a fabric image can be transferred into spatial frequency by fast Fourier transform owing to the fabric's periodicity. Once a defect occurs in the fabric, its periodicity is changed so that the corresponding intensities at the specific positions of the spectrum obviously change. These intensities can act as characteristic parameters and can be substituted in the ANN for learning. Altogether, nine parameters derived from the spectrum have been selected by the ordinary method, which provides the characteristic parameters without any extra modification, and by the statistical method, which modifies the characteristic parameters with variations between the defective and normal fabrics. Of the two plain fabrics used (with densities of 70 X 60 and 65 X 45), for each fabric, the results show that the total classification rates each above 96%. The total classification rate is 88% with the statistical method while the ordinary method is 24% if only one fabric is selected and the learned mode is applied for a new, unlearned fabric. The statistical method can be used for fabric defect recognition, and any inconvenience caused by various specifications of warp and weft densities can be minimized.
Topographic Study of Glass Fibers by Atomic Force Microscopy
Authors: El Achari A. , Ghenaim A. , Wolff V. , Caze C. , Carlier E.
Published: March 2008

To better understand certain physical behaviors of glass fibers used to reinforce a polymer matrix (in composite materials), it is necessary to know their topography. In this paper, E glass fibers are studied using atomic force microscopy (AFM) and scanning electronic microscopy (SEM). To compare three different kinds of fibers (uncoated or virgin glass fibers and those coated either with an epoxy or aminosilane coupling agent only or with a complete sizing), their topography is analyzed using AFM and SEM, the former permitting the mean rugosity ( Ra) measurement of the fiber surface. Virgin (uncoated) glass fibers show a relatively smooth structure ( Ra = 13 nm) with, here and there, bumps that look like craters. Fibers coated with a coupling agent alone have a non-uniform structure because areas all along the length of each fiber are torn off when it is separated from others in the glass roving. Grooves appear when the coupling agent is removed from the fiber's surface; otherwise, there are longitudinal bumps. Fibers coated with a complete sizing have no tom-off areas. The whole to pography is regular, bumps seldom protrude from the overall surface plane, and the roughness value is always lower than that of virgin fibers.
Identifying Fabric Structures with Fast Fourier Transform Techniques
Authors: Bugao Xu
Published: March 2008

The Fast Fourier Transform (FFT) plays a very important role in image processing and pattern recognition. Since a woven fabric consists of regular repeating units, the FFT is particularly useful for analyzing periodicity, directionality, and spacing of re peating units in the fabric. This paper describes procedures for applying FFT techniques in image processing to identify weave pattern, fabric count, yarn skewness, and other structural characteristics of woven fabrics. A color scanner is used to digitize fabric images (two-dimensional functions in a spatial domain), and a customized software package is used to apply the FFT to the images. A power spectrum image is derived from the FFT of an image, and considered a two-dimensional function in a frequency domain. Peaks in the power spectrum image stand for frequency terms of periodic elements, from which basic weave patterns (e.g., plain, twill, satin, etc.) can be rec ognized. A radial function and an angular function, derived from the power spectrum, are used to measure the coarseness and directionality of the periodic elements. By selecting power peaks in a certain direction to reconstruct the image, warp or weft elements can be extracted to facilitate fabric count and skewness measurements. Fourier filtering, that is, image filtering in the frequency domain, is used to suppress noise and to select features that have a certain range of frequencies. Fabrics with various weave patterns and yarn counts are tested using the FFT techniques.
Applications of AFIS Fineness and Maturity Module and X-Ray Fluorescence Spectroscopy in Fiber Maturity Evaluation
Authors: Bradow Judith M. , Hinojosa Oscar , Wartelle Lynda H. , Davidonis Gayle , Sassenrath-Cole Gretchen F. , Bauer Philip J.
Published: March 2008

Worldwide round-testing and calibration of the nep-counting and fiber-length mod ules of the Zellweger Uster advanced fiber information system (AFIS) are well advanced. Lack of appropriate quantitative calibration standards for fiber maturity has limited similar development of the prototypic AFIS fineness and maturity (F&M) module. A combination of calcium x-ray fluorescence Spectroscopy (Ca-XRF) and AFIS-F&M map ping of fiber quality from twenty-one days post anthesis (DPA) to boll opening (56 DPA) permits direct comparisons of AFIS-determined fiber physical maturity (as micronAFIS, circularity, and cross-sectional area) with fiber chronological maturity (as DPA) and physiochemical maturity (as Ca-XRF). The AFIS-F&M module is a powerful tool that makes possible quantitative comparisons of fiber maturity across time (during fiber development and in different crop years), across space (different boll and locule positions and different growing areas), within single bolls and locules, and between cotton varieties and species.
Automatic Assessment of Carpet Wear Using Image Analysis and Neural Networks
Authors: Van Steenlandt W. , Collet D. , Sette S. , Bernard P. , Lüning R. , Tezer L. , Böhland K.H. , Schulz H.J.
Published: March 2008

During the last few years, many efforts have been made to find an objective method to assess the appearance change of carpets after wear tests. Image analysis and digital image treatment seemed to be useful tools and research often showed fairly good results, but the method was always too limited to provide an overall solution. This paper discusses some of the most promising results of research for an automatic as sessment method for cut pile carpets.
A Comprehensive Stress and Breakage Analysis of Staple Fiber Yarns
Authors: Önder Emel , Baser Güngör
Published: March 2008

This paper, which is a preliminary to a general investigation of the stress-strain and breakage behavior of staple yarns, deals with the stress analysis of a staple yarn under axial strain, based on an ideal yarn geometry that allows for fiber migration, assuming conical helix fiber paths. The position and dimensions of a yarn element based on this conical helix model are defined first, in relation to yarn dimensions, and the radial equilibrium conditions are obtained. The axial stress at any point on the yam cross section under a given strain is then expressed by using the characteristic stress-strain curve of the fiber for both small and large strains. Thus the stress distribution over the cross section can also be determined.
Textile Crosslinking Reactions to Reduce the Fibrillation Tendency of Lyocell Fibers
Authors: Nicolai M. , Nechwatal A. , Mieck K.P.
Published: March 2008

Lyocell fibers have extraordinary textile properties, but they show a distinct tendency to fibrillate in the wet state. Treatments with crosslinking compounds used for textile finishing could be a practical means of controlling this problem. Some polyfunctional reactive dyestuffs also greatly increase wet abrasion resistance. Fiber tenacity decreases slightly compared to reactive compounds used for easy care finishing.
A Comprehensive Stress and Breakage Analysis of Staple Fiber Yams
Authors: Önder Emel , Baser Güngör
Published: March 2008

This paper contains the theory developed to describe the breaking mechanism of single staple fiber yams, based on the ideal conical helix model and the stress and breakage theory given in Part I. The computer analysis program is based on an al gorithm describing the slipping and gripping behavior of the fibers leading to final breakage. For verification of the theory, single worsted yams are tested for constant rate of extension strength.
Evaluating Chemically Retted Kenaf Using Chemical, Histochemical, and Microspectrophotometric Analyses
Authors: Morrison W.H. , Akin D.E. , Ramaswamy G. , Baldwin B.
Published: March 2008

Bast ribbons from Guatemala 45 (G-45) and Tainung 1(T-1) cultivars of kenaf ( Hibiscus cannabinus ) were chemically retted for 1 hour in boiling 7% NAOH + 0.5% NaHSO4, after which they were neutralized, washed, and air dried. Gas-liquid chro matographic analysis of extracts from unretted and chemically retted ribbon showed a decrease in syringyl and guaiacyl groups (indicative of lignin ) and xylose, arabinose, and uronic acids (indicative of hemicellulose and pectin). Glucose residues, indicative of cellulose, did not decrease in amount. Sections histochemically stained for lignin and unstained sections examined by ultraviolet absorption microspectrophotometry indicated that syringyl lignin predominated, but guaiacyl lignin was higher in the middle lamellae than in the secondary wall. Tip and base sections showed clear dif ferences in phenolics and carbohydrate content, which could be related to maturity. However, it appeared that syringyl groups were removed to a greater extent from the base sections and pectin was removed to a greater extent from the tips. Breaking strength was significantly greater for the tip than for the base, with no difference in percent elongation between regions.
Multifunctional Polymeric UV Absorbers for Photostabilization of Wool
Authors: Riedel Jan-H. , Höcker H.
Published: March 2008

Photoyellowing of wool can be reduced up to 50% when polymeric UV absorbers with (meth)acrylate backbone are applied. UV absorbers derived from hydroxyphen ylbenzotriazole are most effective. Degradation of photolabile amino acids like tryp tophan and formation of cysteic acid are reduced. The mechanical properties of wool measured by abrasion resistance and bundle tensile strength tests improve with poly meric multifunctional UV absorbers. Resistance to washing of the polymers on wool fibers improves as compared with a low molecular weight stabilizer. Despite additional hydrocarbon and fluorinated side groups, the water repellent effect of polymeric UV absorbers is weak.
Measuring Fiber Orientation in Nonwovens
Authors: Pourdeyhimi B. , Ramanathan R. , Dent R.
Published: March 2008

In nonwovens, fiber orientation is an important characteristic because it directly influences the properties of the material. In a series of papers, we plan to explore the viability of image analysis algorithms for characterizing fiber orientation. In the first part of this series, we present a simulation scheme to produce images to test these different algorithms. As part of the series, we will present a direct tracking method in Part II, as well as Fourier and flow field analyses in subsequent parts for characterizing fiber orientation.
Mechanical Properties of a Migrating Fiber
Authors: Xiaoming Tao
Published: March 2008

A mathematical model of a helix with variable radius is developed to analyze geo metric and mechanical properties of a migrating fiber. The factors concerned include the frequency and amplitude of fiber migration as well as the equivalent radial position and equivalent helix height of the fiber. This treatment permits the application of experimentally determined migration patterns defined by those factors. The derived properties are the curvature and torsion components of the migrating fibers, bending moments, torque, strain energy distribution, and total strain energy. The terminal force and couple are calculated as functions of the length of the helix axis. A critical migration amplitude is identified where the axial component of the couple and trans verse component of the force change their direction. The implication of these behaviors for yam properties such as total yam torque and local pressure distribution is also revealed. Cylindrical and sinuous helices are compared, with the effects of the amplitude and frequency of fiber migration quantitatively determined.
Disperse Dyeing of Nylon 6 Fibers with 1,4-Diaminoanthraquinone in the Presence of Didodecyldimethylammonium Bromide
Authors: Kim Ik-Soo , Kono Kenji , Takagishi Toru
Published: March 2008

The dyeing behavior of 1,4-diaminoanthraquinone (1,4-DAA) on nylon 6 fiber in the presence of didodecyldimethylammonium bromide (DDDMAB) is investigated. Both dyeing rate and dye saturation value of 1,4-DAA improve considerably with DDDMAB, compared with a dyehouse grade of 1,4-DAA, Miketon Fast Red Violet R. There is no evidence for a reduction in T g of the fiber pretreated with aqueous DDDMAB solution. The apparent solubility of 1,4-DAA in aqueous DDDMAB solution as well as the amount of DDDMAB adsorbed onto nylon 6 fiber is large. The enhanced dyeing properties of the fiber in the presence of DDDMAB are attributed to the formation of the concentrated layer of monomeric dye molecules on the fiber surface.
Ultraviolet Radiation Curing Treatments for Shrink-Resistant Wool Fabric
Authors: Dodd K.J. , Carr C.M. , Byrne K.
Published: March 2008

The application of uv curing and corona discharge technology to textiles is intro duced and discussed, The influence of uv photoreactive monomer on the shrinkage and mechanical properties of corona and nonpretreated 100% wool gabardine fabric is detailed. Machine washability can be achieved at low add-on by incorporating a uv curable silicone into the formulation and a post-cure steam treatment.
Vapor Breakthrough from Liquid Drops Impacting Air-Permeable Chemical Protective Fabric
Authors: Scheller B.L. , Rivin D. , Segars R.A.
Published: March 2008

The interaction between drop impact and vapor breakthrough for several kinds of air-permeable fabric composites (an outer shell with an adsorbent liner) is determined under convective flow conditions. Vapor breakthrough is measured using methyl sali cylate, a chemical agent simulant, for static and dynamic liquid drop placement on either the shell fabric alone or in combination with an activated carbon-loaded foam liner backing. Vapor concentration, detected by means of a photo-ionizer, is used to determine breakthrough curves, while image analysis provides a quantitative charac terization of the impact behavior of the liquid drops by measuring liquid spreading. splashing, and breakthrough. Drop impact velocities up to 6 m/s are measured on cotton/Kevlar®/nylon and cotton/nylon twill weave outer shell fabrics. For static drops, fabric composites with an outer wicking fabric give much lower total vapor breakthrough than do nonwicking fabrics, whereas for dynamic drops at subterminal impact velocities, the difference between nonwicking and wicking shell fabrics is re duced because of surface spreading and splashing. There is an inverse correlation be tween wetted area and vapor breakthrough due to localized vapor saturation of the adsorbent liner fabric. Below a critical drop velocity of 4.5 m/s, there is no direct liquid penetration through the shell fabric.
Comparing Dynamic and Static Methods for Measuring Thermal Conductive Properties of Textiles
Authors: Jirsak Oldich , Gok Telem , Ozipek Bulent , Pan Ning
Published: March 2008

Dynamic and a static methods for measuring thermal conductivity of textiles have been developed, and the measuring processes and results are described in detail in this paper. Three different textile materials are used for the actual test. and the data are analyzed, illustrated, and compared. Moreover, a theoretical model is used to obtain the temperature-time curves as predictions corresponding to the dynamic method, and comparisons of the theoretical predictions and experimental results are provided. The static and dynamic methods are also compared, and their applicability to porous media like textiles is discussed.
Analytical Technique for Characterizing the Initial Stage of the Dyeing Process
Authors: Muraoka Yoichiro , Ito Hiraku , Fujiwara Tomoko , Igarashi Chiaki , Nishizawa Kazuo
Published: March 2008

A convenient experimental apparatus is developed for analyzing the initial stage of several seconds at the start of the dyeing process under rapid adsorption conditions. A cationic dyeable acrylic fiber is dyed at 90°C and pH 6.4 with 0.002% methylene blue solution at a 500:1 liquor ratio. The fiber is left in the 90°C steamed atmosphere for 30 minutes before dyeing. The wavelength of the 668 nm monochromatic light beam transmittance is detected with multiple optical glass fibers inserted directly in the dye bath. Six percent of the dye uptake in the fibers after 2 hours' dyeing is adsorbed before I second. In case of a cationic dyeable polyester fiber, 9% is adsorbed in the same period.
Hexagonal Packing of Intermediate Filaments (Microfibrils) in α-Keratin Fibers
Authors: Feughelman M. , James Veronica
Published: March 2008

Electron micrographs of cross sections of highly oriented α-keratin fibers show the presence of intermediate filaments (IF) (microfibrils) packed parallel to each other in hexagonal arrays. Because of the presence of this ordered packing, some form of in terfibrillar linkage or interaction is believed to exist between neighboring IFs in the six hexagonal directions. The possible presence of such linkages has already been sug gested from the mechanical behavior of wool fibers in formic-acid-water solutions up to concentrations of 75% v/v. In water, the IFs are arrayed parallel to each other and . to the axis of the wool fiber. In the formic acid solution, the fibers swell considerably radially, with a smaller longitudinal contraction occurring up to a concentration of 75% formic acid in water. The contraction is a result of the bending or kinking of the IFs to accommodate the diametral swelling of the fiber with fixed interfibrillar linkages. Geometric calculations based on the presence of these linkages in the hexagonal di rections yield a spacing of 46 to 51 nm in the direction of the IFs for linkages between any two neighboring IFs. This result agrees with the observed meridional x-ray dif fraction spacing of 47.0 nm for α-keratin fibers. An IF model is proposed with potential interaction sites for the hexagonal directions. The model is based on the presence of eight tetramers of helices and "tails" in the outer ring of the IF, with the linkage sites in the high sulphur tails. The model concurs that the interfibrillar linkages, which are present in the matrix, are the source of the meridional repeat of 47 nm. This repeat was modified in x-ray diffraction data for human hair taken from diabetic patients, placing the modification of the hair in the labile matrix structure where the linkages exist.
Crosslinking of Sulfonated Cotton Cellulose
Authors: Han Tsung-Yuan , Chen Cheng-Chi
Published: March 2008

Various degrees of sulfonated and unsulfonated cotton fabric samples are treated with DMDHEU in the presence of a mixed catalyst under mild curing temperatures. At a given DMDHEU concentration in the bath, the nitrogen contents of the finished fabrics increase with increasing degrees of sulfonation, while the formaldehyde content de creases. ΔWCRA values increase with increasing sulfonation at the same values of ΔDCRA and ΔTSR. For a given value of CL/AGU, the ΔWCRA and CL length values increase as the sulfonation degree of the fabrics increases.
Preparation of Organic Solvent-Soluble Proteins and Their Application: Solute Permeabilities and Dyeing Properties of Polyacrylonitrile/Modified Protein Composite Membranes
Authors: Park J.C. , Yamaguchi T. , Hori T. , Yamakoshi K.
Published: March 2008

To understand the structure of composite membranes prepared from polyacrylonitrile (PAN) and modified milk whey (MMW) or egg white (MEW), obtained by reacting with 2,4-tolylen diisocyanate, we have investigated the membrane potential, solute perme ability, and dyestuff adsorption. The membrane potential measurements confirm that at least some parts of modified protein components in composite membranes with high modified protein contents are incorporated by passing through the membranes. Solute permeability, equilibrium adsorption, and the adsorption rate of some dyestuffs through/on the composite membranes increase with increased modified protein content in the membrane. The properties of MMW/PAN and MEW/PAN are quite different because their characteristic structures are different: the shape of "island" MMW in "sea" PAN is elliptical, and that of "island" MEW is flat and oriented parallel to the membrane. Furthermore, equilibrium Methylene Blue (MB) adsorption on the composite mem branes indicates that there are some interactions between PAN and MMW up to a ratio of about 6.5 g (MMW)/100 g (PAN), and the interacted MMW parts have no affinity for MB.
Mechanisms of Yarn Twist Blockage
Authors: Menghe Miao
Published: March 2008

Yarn twist blocking occurs when a yarn slides over a yarn guide or other machine part. This paper reviews previous investigations on twist blockage, the influence of yarn and guide conditions, and especially twist blocking mechanisms. The twist block ing mechanisms so far suggested are all based on a continuum yam model—a yarn treated as a flexible and laterally deformable cylindrical body. The validity and draw backs of these mechanisms are discussed. A further mechanism based on the continuum yarn model—twist blocking due to biased normal pressure distribution across the yarn—is proposed, and yarn twist blocking phenomena are then re-examined by treat ing the yarn as an array of mobile fibers. The yam-to-guide frictional force pushes the fibers in front of the guide to increase their helix angles, and pulls the fibers behind the guide to decrease their helix angles. The new mechanism is put to the test by comparing predicted twist blockage with previous observations, and is found to offer satisfactory interpretations.
Iron Salts in the Post-Metallization of Mordant Dyes
Authors: Bardole Heather A. , Freeman Harold S. , Reife Abraham
Published: March 2008

Iron (II) and iron (III) salts are used as mordanting agents in lieu of chromium ions, as a source reduction approach to eliminating chromium in dye effluents following the post-metallization of acid mordant dyes. Specifically, wool fabric is dyed with Mordant Yellow 8, Yellow 30, Orange 3, Orange 6, Red 7. Red 19, Blue 1, Blue 9, Blue 13, Brown 40, Black 1, and Black 11, then treated with iron salts. The complexes are characterized by negative ion fast-atom bombardment mass spectrometry and absorp tion spectrophotometry, and the after-treated fabrics are evaluated for lightfastness and washfastness. Mordant dyes possessing either ortho, ortho'-bis(hydroxy)- phenylazopyrazole or ortho-hydroxy-phenylazonaphthol substituted chromophoric sys tems form the corresponding 1:2 metal : dye complex and undergo significant improve ments in lightfastness and washfastness following metallization.
Computer Simulation of Mechanical Properties of Nonwoven Geotextiles in Soil-Fabric Interaction
Authors: Adanur Sabit , Liao Tianyi
Published: March 2008

The mechanical behavior of nonwoven geotextiles in soil-fabric interaction is in vestigated through laboratory experiments and theoretical analysis. A computer model is presented to simulate geotextile performance in pullout tests. The model parameters are based on single fiber properties and the fiber orientation distribution function. A new finite element method is used to calculate numeral solutions of stress and strain distribution in different regions developed in the fabric during the pullout test. The pullout load versus displacement curves of the samples verify the simulated results, which are in good agreement with those obtained from pullout experiments.
Phosphatidilcholine Liposomes as Vehicles for Disperse Dyes for Dyeing Polyester/Wool Blends
Authors: Martí M. , Coderch L. , De La Maza A. , Manich A. , Parra J.L.
Published: March 2008

This study describes the role of liposomes as carriers in dyeing polyester/wool blends with disperse dyes. Dye exhaustion and bonding on polyester/wool samples are studied under different experimental conditions—the liposome amount, the dye amount, and the temperature—to achieve optimal conditions. The results are compared with those obtained with and without conventional dyeing auxiliary products. Although bath exhaustion is higher in the presence of commercial carriers, the dye bonded in creases markedly in the presence of liposomes in the two fibers. The role played by liposomes in polyester/wool blend dyeing can lead to a new strategy for this process.
Hydrolysis of Cotton Cellulose by Engineered Cellulases from Trichoderma reesei
Authors: Cavaco-Paulo Artur , Almeida Luis , Bishop David
Published: March 2008

We have characterized the activities of TC, EG-rich, and CBH-rich cellulases from T. reesei and have shown that their activities towards cotton fabrics are influenced by ionic strength and adsorbed ionic species as well as by temperature and pH. Adsorption and kinetic experiments confirm that increasing mechanical agitation favors EG attack by greatly increasing the availability of sites for EG adsorption. It is not clear whether this is a consequence of fiber fibrillation damage or of improved access to fiber surfaces deep within the fabric structure. The enhanced rate of cellulolytic hydrolysis of mer cerized cotton and the inhibitory effects on reactive and direct dyed fabrics are ex plained mainly in terms of increased or reduced availability of adsorption sites for CBHS and EGS. The implications for textile finishing are far-reaching. It is clear that a fabric's processing history (especially mercerizing and dyeing), construction, and level of ap plied mechanical agitation can be as important as the choice of enzyme composition and concentration in determining the consistency and quality of the end result.
Predicting Energy Requirements for Moulding Flexible Polyurethane Foam Sheets
Authors: Yu W.M. , Yeung K.W. , Harlock S.C. , Leaf G.A.V.
Published: March 2008

Moulding is a method of inducing a permanent three-dimensional shape in ther moplastic materials by heat setting. Using polyurethane foam moulding for brassiere pads as an example, the most essential problem is to predict the optimum conditions that result in the best cup shape conformity with the most efficient use of heat energy. To study the best moulding quality, a response surface method is used to examine the relationship between a measured response (shape conformity) and a number of input variables (moulding temperature and time). The optimum moulding conditions for individual foam types can be found by examining the contour plots of response sur faces. A relationship between the moulding temperature and time is then derived. The heat energy required for optimum moulding can be expressed in terms of these two moulding variables and three other foam attributes ( mass, specific heat, and thermal conductivity).
Breeding Cottons with Higher Yarn Tenacity
Authors: May O. Lloyd , Taylor Robert A.
Published: March 2008

Stronger cotton yams are needed by the textile industry as knit and woven fabric manufacturing speeds increase, thus placing greater strain on cotton yarns. We compare fiber properties as selection criteria for the genetic improvement of yarn tenacity in a breeding population consisting of twenty-five cotton germplasm lines grown for two years at two locations near Florence, SC. Fiber properties measured with the fibrograph, Stelometer, fibronaire, and Arealometer are obtained on lint from each experimental line in this population, along with ring spun yam with a tenacity of 27 tex (22 Ne). Among individual fiber properties, selection for 50% fiber span length results in the greatest gain in yarn tenacity. Simultaneous selection for low Micronaire reading, long 50% fiber span length, and high fiber tenacity improve yam tenacity more so than selection for individual fiber properties. Selecting for fiber properties measured with the Arealometer generally results in lower gains in yarn tenacity. We show individual and combinations of fiber properties that are useful as selection criteria for yarn tenacity improvement.
Damage Growth in Prestressed Plain Weave Fabrics
Authors: Godfrey Thomas A. , Rossettos John N.
Published: March 2008

A simplified micromechanics approach is used to develop a mathematical model to predict damage growth in prestressed plain weave fabrics near sites where yams are broken. Stress concentration in the yams neighboring yarn breaks is determined as a function of increasing loading. An evaluation of the load redistribution around the damage region includes a determination of the frictional slip of broken yams. Consid eration of equilibrium and deformation of constituent yams leads to linear differential equations for yarn displacements applicable to distinct regions where slipping does and does not occur. Slip frictional forces depend on yam normal contact forces at cross over points resulting from crimp interchange, Kawabata's model [12] is modified and used to motivate an analysis of frictional load transfer. The equations are nondimen sionalized, and dimensionless parameters involving both geometry and material prop erties are identified.
Mathematical Simulation of Heat and Moisture Transfer in a Human-Clothing-Environment System
Authors: Li Y. , Holcombe B.V.
Published: March 2008

A mathematical model has been developed to describe the dynamic heat and moisture transport behavior of clothing and its interaction with the human thermoregulation system under transient wear conditions. A modification of Gagge's two-node model is used to simulate the human physiological regulatory responses. In clothing, heat and moisture transport is coupled with the sorption or desorption of water vapor in the fibers and the associated energy changes. If the physical activity and ambient conditions are specified, the model can predict the thermoregulatory responses of the body, to gether with the temperature and moisture profiles of the clothing. Experimental mea surements with garments made from fibers with different levels of hygroscopicity are compared with predictions by the model. There is good agreement between prediction and experiment for skin and fabric temperatures and the relative humidity of the cloth ing microclimate.
Synthesis of a Quaternary Ammonium Derivative of Chitosan and Its Application to a Cotton Antimicrobial Finish
Authors: Young Ho Kim  , Choi Hyung-Min , Jung Hee Yoon
Published: March 2008

A quaternary ammonium derivative of chitosan, N-(2-hydroxy)propyl-3-trimethy lammonium chitosan chloride (HTCC), is synthesized as an antimicrobial finish for cotton using a reaction of glycidyltrimethylammonium chloride (GTMAC) and chitosan. Results indicate that the degree of substitution (DS) in HTCC calculated by chloride content is a function of the reaction temperature and mole ratio of GTMAC and NH2 in chitosan. Excess amounts of GTMAC are generally needed to obtain a water-soluble fraction of HTCC. A minimum DS of 0.6 is needed to yield water-soluble HTCC. Syn thesized HTCC is analyzed by FTIR, H 1-NMR, TGA, and x-ray diffraction techniques. At very low concentrations, such as 0.025% owb, HTCC shows superior antimicrobial ac tivity indicated by an almost 100% bacterial reduction, whereas 1 % owb chitosan shows only 30% bacterial reduction. Since HTCC is soluble in water, we have examined several methods to increase the laundering durability of cotton treated with HTCC. Among them, application of a nonionic binder considerably improves the laundering durability of HTCC-treated cotton.
False Twist in Core Yarn Friction Spinning
Authors: Merati Ali Akbar , Konda Fujio , Okamura Masaaki , Marui Etsuo
Published: March 2008

We have analyzed false-twist distribution in filaments along core yams produced on a friction spinning machine, considering the effective parameters for imparting twist to the filaments and yarns. The theoretical analysis is based on twist distribution along the conical yarn tail. Twist is applied to the yam tail by suction air pressure and rotation of the friction rollers. The theoretical results are compared with the experimental data. The results show that although, theoretically, the twist imparted to a filament is zero, there is still some twist in the filament in both directions (S and Z) in a short yarn length. As the sample length increases, these twists combine and cancel each other. The resulting twists tend toward zero in longer yam samples. Filament pre-tension also affects the false twist of the filament. The results show that the remaining twist in filaments in non-pre-tensioned yams is greater than that in pre-tensioned yams.
Numerical Simulation of the Melt Spinning of Hollow Fibers
Authors: Tae Hwan Oh  , Moo Seok Lee  , Sang Yong Kim  , Hyun Joo Shima
Published: March 2008

The melt spinning process for hollow fibers is numerically simulated using a finite element method. The dynamics of hollow fiber spinning can be described by a two- dimensional finite element method that considers the deformation of two free surfaces. The initial grid is constructed and the new one is generated iteratively until it reaches a convergence. Converged solutions are obtained through successive iterations. A large rate of area reduction and rapid solidification are the characteristics of melt spun hollow fibers, compared with circular cross-sectional fibers. Analysis of the effect of spinning parameters on the process shows that spinning temperature and mass throughput rate are the most critical variables in controlling the hollow portion of the fiber, followed by take-up velocity and quench air velocity. Quench air temperature has a smaller effect than the other variables. The effect of changing process variables decreases as the die gap becomes narrow.
Nonformaldehyde Durable Press Finishing of Cotton Fabrics by Combining Citric Acid with Polymers of Maleic Acid
Authors: Yang Charles Q. , Lan Xu  , Shiqi Li  , Yanqiu Jiang
Published: March 2008

In our previous research, we investigated the use of two polymers of maleic acid, i.e., the homopolymer (PMA) and the terpolymer (TPMA), for crosslinking cotton cellulose. We found that PMA and TPMA were less effective than 1,2,3,4-butanetetracarboxylic acid (BTCA) due to the low mobility of the anhydride intermediates to access the cellulosic hydroxyl during a curing process. We found that the hydroxyl of citric acid (CA) hinders its esterification with cotton cellulose, and so is less effective than 1,2,3-propanetricar boxylic acid as a crosslinking agent for cotton. We also found that CA esterifies the anhydride intermediate of PMA or TPMA on the cotton fabric formed under curing con ditions. In this research, we observed a synergistic effect by combining PMA or TPMA with CA as co-crosslinking agents for cotton fabrics. The combination of TPMA/CA is more effective than the PMA/CA combination for imparting wrinkle resistance to the finished cotton fabrics. Cottons finished with the TPMA/CA combination show superior durable press performance, good laundering durability, and high fabric strength retention. The superior performance and cost effectiveness of this new finishing system makes it feasible as a replacement for formaldehyde-based durable press finishes.
Relationship Between Flame Retardation and Phase Transition Behavior of Polyester Fabrics Treated with a Bromine-Containing Compound
Authors: Kubokawa H. , Hatakeyama T.
Published: March 2008

Poly (ethylene terephthalate) (PET) fabrics are treated with meso-1,2,3,4-tetrabro mobutane (TBB) to investigate flame retardation. The limiting oxygen index (LOI) value increases with an increasing amount of absorbed TBB (ATBB) and reaches 28.1 % when ATBB is 10.20% owf. The slope of LOI is 1.14%/% owf from 0 to 4.65% owf of A TBB, and the slope decreases 0.31%/% owf at a region higher than 4.65% owf. The phase transition behavior of treated samples, investigated with differential scanning calorim etry, reveals that the depression of the melting initial temperature ( T m) is directly proportional to the LOI value. Flory's equation for the depression of the melting point in polymer-diluent systems is applied to the PET-TBB system. We conclude that TBB molecules, which have strong affinities for PET segments in the region below 4.65% owf, show greater retardation for flammability.
Effect of Strand Spacing and Twist Multiplier on Cotton Sirospun Yarn
Authors: Cheng K.P.S. , Sun M.N.
Published: March 2008

For combed cotton yarns, the wider the strand spacing is in Sirospun, the better the yarn properties are in terms of tenacity, Uster hairiness, abrasion resistance, and trapped strand twist.
Tropical-Weight Wool-Rich Blend Fabrics with Unique Draping Characteristics
Authors: Arnold L.N. , De Boos A.
Published: March 2008

Summer-weight wool-rich blend fabrics with different warp and weft bending char acteristics are produced by weaving weft yams consisting of fine wools blended with bicomponent synthetic polyester or polyolefin fibers into pure wool warps. The differ ential bending properties of the fabrics are developed during finishing. The effects on the bending and shear characteristics of the fabrics are considered after each stage of the finishing sequence. Wool/polyester fabrics are more susceptible to the effects of steaming during finishing than wool/polyolefin blends. Conditions during finishing must be carefully controlled if the optimum fabric properties are to be obtained. Trials confirm that summer-weight fabrics with engineered bending and shear characteristics can be produced from blends of wool with bicomponent synthetic fibers by choosing suitable finishing sequences.
Influence of Hydrolytic and Chemical Treatment on the Mechanical Properties of Aramid and Copolyaramid Fibers
Authors: Springer H. , Abu Obaid A. , Prabawa A.B. , Hinrichsen G.
Published: March 2008

Commercial PPTA fibers ( Kevlar 49® and Twaron 1055®) and copolyaramid fibers (Trevar®) are subjected to various hydrolytic and chemical treatments. Tensile mod ulus, tensile strength, and elongation at break are measured, and mechanical property deterioration is compared. Copolyaramid fibers show improved hydrolytic stability and chemical resistance compared to PPTA fibers. The time dependence of degradation pro cesses can be described by two decreasing exponential functions. WAXS measurements detect only slight differences in the crystalline structure and superstructure of the treated fibers. Thus, the main origin of mechanical degradation is the destruction of intercrys talline links such as tie molecules or tie crystallites.
Effect of Environmental Relative Humidity and Damage on the Tensile Properties of Flax and Nettle Fibers
Authors: Davies G.C. , Bruce D.M.
Published: March 2008

The effects of environmental conditions and mechanical damage on the tensile stiffness and strength of two natural fibers, flax and nettle, are investigated. Flax and nettle both contain cellulosic fiber bundles in the outer layer of the plant, each bundle comprising many individual cells bonded together. Novel experimental equipment is designed and constructed to measure, under varying environmental conditions, the static and dynamic tensile moduli and the strength of individual fiber cells. As previous work has shown, the tensile modulus is dependent on environ mental relative humidity, but the effect of fiber damage is also significant. There is a correlation between the extent of damage, measured as the proportion of the fiber showing as bright under a polarizing microscope, and the modulus. When the effect of damage is taken into account, there is a consistent relationship between modulus and relative humidity.
Computer Aided Analysis of Loom Beating-up Mechanisms
Authors: Youjiang Wang  , Hui Sun
Published: March 2008

Analysis and design of the beating-up mechanism is of great importance for im proving loom performance. Computer aided design and analysis tools are used to study different kinds of beating-up mechanisms, including the 4-link and 6-link systems, and their characteristics are compared with those of the conjugate-cam mechanism. Results from models with varying geometric parameters are presented, revealing that the com puter tools are effective and useful in analyzing and designing beating-up mechanisms with smoother operation, lower noise and vibration, and higher speeds.
A Worsted Fabric Expert System
Authors: Fan J. , Hunter L.
Published: March 2008

Part I of this two-part series reports on the development of an expert system for assisting in the engineering design process of worsted fabrics. This part briefly dis cusses the process of fabric engineering and the structure, components, and functional features of the recently developed worsted fabric expert system (WOFAX).
Interaction of Process and Material Parameters in Air-Jet Spinning
Authors: Rajamanickam Rangaswamy , Patel Manish , Hansen Steven M. , Jayaraman Sundaresan
Published: March 2008

The first part of this paper deals with the interaction of first and second nozzle pressures in air-jet spinning of microdenier polyester/cotton blended yams. The results show that the first and second nozzle pressures interact with each other to determine yarn strength. This is because both the number of wrapper fibers and the length of wrappings formed at a particular first nozzle pressure depend on the level of the second nozzle pressure and vice versa. There is an optimum number of wrapper fibers and wrapping lengths that yields the maximum yarn strength, and this optimum level can be obtained at several different nozzle pressure combinations because first and second nozzle pressures interact with each other. However, it would be advantageous to use the lowest of these nozzle pressure combinations because of significant savings in energy costs. The second part of this paper investigates the effect of yarn delivery speed, first nozzle pressure, and blend ratio on the hairiness profile of microdenier polyester/cotton blended air-jet spun yams. The results show that yarn hairiness increases with increased yarn delivery speed and first nozzle pressure, but decreases with increasing amounts of polyester in the yarn. Also, the three factors (yarn delivery speed, first nozzle pressure, and blend ratio) interact with one another in determining yarn hairiness.