bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of Finishing Processes on Flame Resistance of Knitted Fabric
Authors: Ozcan Gulay , Dayioglu Habip , Candan Cevza
Published: March 2008

In this study, knitted fabrics are chosen to investigate the effect of their finishing properties on flame resistance. Finishing processes (bleaching, dyeing, and some chemical additives used for bleaching and dyeing) that affect fabric flammability are defined and an experimental program is followed. The level of flammability of the treated fabrics is measured in accordance with the BS 5438 vertical flammability test method because its results are very similar to real fabric burning behavior. Finally, experimental results are evaluated according to a statistical analysis with the SPSS program, and how and at which level chemical parameters affect knitted fabric burning behavior is defined.
Drafting Dynamics of Fine Denier Polyester Fibers
Authors: Aydogmus Korkmaz Yasemin , Behery Hassan M.
Published: March 2008

It is important to understand the role of fiber properties in the drafting process. Finer denier fibers may have different drafting behaviors than average denier fibers, such as drafting force, required roller settings, draft distribution, and velocity change zone. The objective of this work is to study the interaction of specific fiber fineness values and the drawing machine. Three different fine denier polyester fibers (0.8, 1.0, and 1.2) are run on a three-over-three roller drafting machine set at six different drafts with three roller settings. A high-speed video camera system observes fiber movements and measures fiber speeds in the drafting zone. In this study, fiber speed and variations in fiber speed are significantly affected by fiber fineness and drafting conditions. Fineness changes drafting behavior by introducing fiber clusters and fiber contact points. The acceleration process depends on the interaction of static and dynamic friction forces at the fiber contact points. Therefore, fiber movement in the drafting zone is not a continuous process, that is, it consists of local acceleration and slowing down of segments of fibers.
Bleachability and Dyeing Properties of Biopretreated and Conventionally Scoured Cotton Fabrics
Authors: Losonczi A. , Csiszár E. , Szakács G. , Kaarela O.
Published: March 2008

Enzymatic (cellulase, pectinase, xylanase) and simple buffer treatments in the presence of a nonionic surfactant improve water wettability of fabrics to a level equal to conven tional alkaline scouring. Caustic scoured fabric is significantly lighter and less colored than all the biopretreated samples. Application of a hydrogen peroxide bleaching subse quent to the biopretreatment is beneficial because it reduces the great color differences between conventionally scoured and biopretreated samples. Bleachability of the pretreated fabrics is better than that of the conventionally scoured sample. Biopretreated fabrics can be dyed with a reactive dye subsequent to the enzymatic treatment without further oxidative bleaching. At higher dye concentrations ( i.e., 1 or 2%), there is no perceptible color difference between the biopretreated and alkaline scoured fabrics in the dyed state. In pale and medium dyeings, however, the color difference is great and perceptible. Bleaching applied subsequent to bioscouring significantly decreases the color difference between the dyed samples pretreated in different ways. None of the pretreatments causes uneven dyeing. Wash fastness of the dyed samples is excellent and unrelated to the pretreatment method.
Effect of Processing and Reactive Dyeing on the Swelling and Pore Structure of Lyocell Fibers
Authors: Kasahara Katsuji , Sasaki Hiroaki , Donkai Nobuo , Takagishi Tohru
Published: March 2008

Lyocell yarns are treated with NaOH, liquid ammonia, high pressure steam, and polycarboxylic acids, then dyed with five reactive dyes. The degree of swelling and the micropore structure of the swollen samples in water are discussed in the context of the results obtained with size exclusion chromatography. The water content of the samples is also measured by centrifugal and chromatographic techniques. A good correlation is found between the values from the different techniques for all samples, except for the samples dyed with bi-functional reactive dyes. The total pore volume substantially increases with NaOH treatment and decreases with high pressure steaming. The pore size distributions for the dyed samples are essentially affected by the dyes used, i.e., depending on dye structure and reactive dye type.
Light Fading and Wash Fastness of Dyed Nanosol-Coated Textiles
Authors: Mahltig B. , Böttcher H. , Knittel D. , Schollmeyer E.
Published: March 2008

Dye molecules are incorporated into silica matrices for textile dyeing. One aim is to develop a method to use inexpensive dyes with simple molecular structures for dyeing completely different kinds of textile materials. Altogether, three different classes of dyes are incorporated—positively charged Astrazone Blue, negatively charged Alizarin S Red, and uncharged Sudan II Blue—using an acidic sol-gel process starting with a solution of tetraethoxysilane and crosslinking agents and the dye in ethanol. By means of dip-coating and padding, these solutions are deposited on three different textiles, polyester, poly amide, and cotton. The incorporation properties were mainly influenced by the properties of the dyes, but improved wash fastness can be achieved by modifying the matrix composition.
Evaluating the Softness of Animal Fibers
Authors: Liu Xin , Wang Lijing , Wang Xungai
Published: March 2008

Softness is an important property of textile fibers, and animal fibers in particular. At present, there is no reliable method for objectively evaluating fiber softness. This paper examines a simple technique of such evaluations by pulling a bundle of parallel fibers through a series of pins. Softer fibers with lower bending rigidities and smoother surfaces should have lower pulling forces. Alpaca and wool fibers are used in this study to validate this technique, and the results suggest that pulling force measurements can reflect differences in fiber softness.
Tensile Properties and Fracture Morphology of Viscose Yarn at High Strain Rates
Authors: Marques Filipa Alexandra , Cabeço Silva Elisabete , Cabeço Silva António , Drean Jean-Yves
Published: March 2008

The tensile behavior of textile yams at high speeds is a problem of great practical interest. Higher speeds induce higher strains and, consequently, a higher probability of yarn breaks. In order to ensure acceptable quality even at the highest spinning or weaving speeds, tensile instruments and testing conditions have to be improved. Therefore, we have developed a new high-speed dynamometer and a new method to subject yams at strain rates similar to those found in current textile operations. We use this high-speed dynamometer to investigate the influence of high strain rates on the tensile properties and fracture morphology of a technical viscose multifilament yarn. Data reveal that rapid straining usually results in higher yarn tensile properties. SEM photos show a characteristic granular fracture morphology, but the yarn surface becomes less granular as the strain rate increases.
Improved Carpet Initial Appearance and Wearability Through Low-Melt Yarn Insertion
Authors: Balasubramanian K.K. , Campbell B.S. , Hancock G. , Helms C.F. , Polk J.E. , Miller R.W.
Published: March 2008

Inter-ply, low-melt yam insertion improves a carpet's resistance to foot traffic, i.e., its resistance to matting. In addition, low-melt yam insertion improves the individual tuft's tip definition in untrafficked carpet and increases its body, i.e., gives it a better showroom appearance. Negatively, the same factors providing these benefits—better inter-ply co hesion and tuft integrity—also give the carpet a slightly harsher feel or hand.
Reuse of Activated Sludge Biomass: Equilibrium Studies for the Absorption of Basic Dyes on Biomass
Authors: Chu H.C. , Chen K.M.
Published: March 2008

The absorption equilibriums of Basic Yellow 24 and Basic Blue 54 dye by an activated sludge biomass (empirical formula, C60H110O27N8S) are studied. The optimum equilibra tion parameters investigated are 12 hours' equilibration time, 0.8 g L-1 biomass dose, 150-300 μm biomass particle size, 300 ppm initial dye concentration, and 30°C dye solution temperature. The experimental results indicate that for two basic dyes with the same chemical class (thiazole azo) and nearly the same molecular weight, the optimum absorption equilibria are the same but the maximum absorption capacities are different. These absorptive differences could exist because the more hydrophobic residues a dye molecule contains, the more basic dyes the biomass absorbs. The results of analyzing equilibration data show that for the absorption equilibria of two basic dyes absorbed by biomass, the Langmuir absorption isotherm is a better fit than the Freundlich isotherm. The absorption process is exothermic in nature and the absorption type is chemisorption.
Predicting the Tensile Properties of Air-Jet Spun Yarns
Authors: Zeng Y.C. , Wang K.F. , Yu C.W.
Published: March 2008

Two modeling methods are used to predict the tensile properties of air-jet spun yarns. A numerical simulation provides a useful insight into the flow characteristics and wrap ping formation process of edge fibers in the nozzle of an air-jet spinning machine. By analyzing the results of the numerical simulation, the effects of nozzle parameters on yarn tensile properties can be predicted. A neural network model provides quantitative predic tions of yarn tenacity. The effects of parameters on yarn tenacity are also determined by the neural network model. Excellent agreement is obtained between these two methods.
An Integrated Approach to Analyzing the Nature of Multicomponent Fiber Blending
Authors: El Mogahzy Yehia
Published: March 2008

This paper presents a detailed analysis of the nature of multicomponent fiber blending using an integrated analytical and experimental approach. This approach is based on classifying the blending phenomenon into four basic modes: structural blending, attribu tive blending, appearance blending, and interactive blending, Structural blending implies the extent of geometric allocations of different fiber segments within the structural boundaries of the fiber strand. This is analyzed using the so-called representation index, which determines the extent of a fiber component's representation in the blend. Attributive blending indicates the extent of the interaction of different fiber attributes within the characteristic boundaries of the fibrous assembly. This is analyzed on the basis of the extent of the linearity and additivity of the characteristics of blended fibers. In this regard. new analytical tools are introduced, including the blending matrix, blend profiles, and blending index. Appearance blending describes the extent of homogenization of a color's or component's apparent intensity in the fiber assembly. This is analyzed on the basis of color contrast in the blend, which is determined by the light intensity of different fiber components. Interactive blending implies the mechanical interaction of fibers within a component and of different fiber components during the blending process. This is determined by the propensity of blended fiber components to opening, measured by the energy required to achieve fiber cluster breakdown.
Impact Resistance of Woven Fabrics
Authors: Termonia Yves
Published: March 2008

A comprehensive model is presented to study the deformation of and damage to woven fabrics under small projectile impacts. The approach dynamically follows the strain wave propagation along each individual yarn away from the impact point. As in previous work, the mechanics of wave propagation is formulated in terms of impulse-momentum balance equations, which are solved at each fiber crossover using a finite difference technique. Our approach explicitly considers the various projectile characteristics (shape, mass, velocity) as well as all fiber properties such as denier, modulus, and tensile strength. Even more importantly, the model allows us to account for slippage of yarns at crossovers and within the clamps. In contrast to previous work, yarn slippage and fracture processes are described with a kinetic approach, which explicitly accounts for their dependence on impact rate. Our model results are in good quantitative agreement with published exper imental data on single-ply fabrics. They also clearly indicate that yarn slippage through clamps—often seen experimentally—is responsible for some salient features observed in ballistic data.
Relationships Between a Cotton Fiber's Specific Surface Area and Its Physical Properties
Authors: Kaewprasit Chongrak
Published: March 2008

The physical properties of six ICCS fibers—B—26, C-36, D-5, E-4, G-17, and I-26-their percent crystallinity, and the amount of absorbed water are measured in order to establish relationships with specific surface areas measured by the absorption of methy lene blue in a liquid phase. The results show the relationships between the surface area as measured by methylene blue absorption and fineness as measured by the gravimetric method, FMT3, and AFIS. Furthermore, there is a linear relationship between the surface area and the water content of cotton fibers, as determined by thermal-balance analysis. There is no clear relationship between the surface area and the percent crystallinity of the fibers.
Effect of Garment Fit on Thermal Insulation and Evaporative Resistance
Authors: Chen Y.S. , Fan J. , Qian X. , Zhang W.
Published: March 2008

This paper reports on an experimental investigation of the effects of garment fit on clothing thermal insulation and moisture vapor resistance, both of which increase with the thickness of the air gap between the garment and the body when the air gap is small. The rate of increase gradually decreases as the air gap becomes thicker, and is much less than the theoretically ideal still air due to natural and forced convection. When the air gap exceeds a certain value, thermal insulation and vapor resistance may decrease with increases in the air gap. Thermal insulation and moisture vapor resistance reach a maximum at a certain air gap thickness depending on fabric properties, wind conditions, and garment fit. Tighter fitting garments are preferable to keep the body warm in windy conditions.
Improving the Color Features of Hemp Fibers After Chemical Preparation for Textile Applications
Authors: Wang H.M. , Postle R.
Published: March 2008

The renewed interest in bast fibers for textile products has focused attention on research in different methods of bast fiber processing. The color properties of bast fibers must be improved during fiber preparation, especially when standard textile processes such as cotton and wool methods are considered. The color properties of hemp fibers are investigated in this paper after chemical processing based on experimental design tech niques. The effects on the fiber color of hemp raw materials and chemical processes are discussed. The results of alkali boiling and peroxide bleaching are analyzed for their significant effects on hemp fiber color.
Vat Dyeing Properties of a Novel Regenerated Cellulosic Fiber
Authors: Shim Woo Sub , Lee Jung Jin , Kim Jae Pil , Chun Sang Wook , Kwak Seung-Yeop , Kim Ik Soo , Ahn Jong Soo , Koh Joonseok , Kwon Yong Ku
Published: March 2008

The dyeing behavior of a novel regenerated cellulosic fiber (enVix®), prepared from secondary cellulose acetate fibers by the hydrolysis of acetyl groups, is investigated with three vat dyes. The effect of liquor ratio, temperature, and dye concentration on the dyeing properties of the enVix and viscose rayon are evaluated. The enVix exhibits better dyeability and fastness than viscose rayon, presumably due to its lower crystallinity.
Crosslinking and Agent Distribution of Cotton Cellulose Treated with Combined Dimethylolethyleneurea and Dimethylol-N,N'-dimethylene-tris-ethyleneurea
Authors: Yen Meng-Shung , Chen Jui-Chin , Chen Cheng-Chi
Published: March 2008

We have used three different processes to treat cotton fabrics with different combined weight ratios of dimethylolethyleneurea (DMEU) and dimethylol-N,N'-dimethylene-tris ethyleneurea (DMDME3EU) as crosslinking agents, and have found that a two-step process of pad(DMDME3EU)-dry-cure-pad(DMEU)-dry-cure yields higher dry crease recovery angles (DCRA), wet crease recovery angles (WCRA), and equilibrium direct dye adsorption values than the other two processes of pad(DMEU)-dry-cure-pad(DMDME3EU)-dry-cure and pad- (mixture of DMEU and DMDME3EU)-dry-cure at the same nitrogen content and a combined ratio of equal concentrations of the two agents. The process of pad(DMDME3EU)-dry-cure- pad(DMEU)-dry-cure also yields higher DCRA values for a given wet crease recovery angle and tensile strength retention and an even crosslinking agent distribution in/on the treated fabrics. At the same time, the DCRA and WCRA values for the pad(DMDME3EU)-dry-cure- pad(DMEU)-dry-cure process are higher than those for the other two processes at a given number of crosslinks per anhydroglucose unit.
Computation of Bending Behavior of Woven Structures Using Optimization Techniques
Authors: Sagar T.V. , Potluri P.
Published: March 2008

This paper describes a mechanical model to predict the behavior of plain-woven fabrics under pure bending. A generalized energy approach that handles the nonlinear properties of constituent yams is used in the formulation. The model takes into account fabric set as well as yam compression previously ignored in many analyses. The model is validated against the experimental data of both monofilament fabrics and glass fabrics, and there is reasonably good agreement. The model gives rise to a computationally efficient algorithm that can be solved using readily available mathematical software based on nonlinear programing optimization techniques.
Changing Yarn Hairiness During Winding— Analyzing the Trailing Fiber Ends
Authors: Jun Lang  , Sukang Zhu  , Ning Pan
Published: March 2008

The change mechanisms of staple yarn hairiness during the winding process are studied using some previously published theories on yarn structures. Of the three kinds of yarn hairiness, the one formed by trailing and protruding fiber ends is analyzed first in terms of the interactions of the fiber ends, the tension disk, and the grooved drum. The various actions on the yarn during the winding process are identified and categorized into two groups: the one pulling the fiber ends and the other providing the resistance. By defining a ratio of the two groups of forces, a criterion of whether a fiber can be pulled out is established. This criterion is then applied to the tension disk and grooved drum, the main sites where actions occur, to investigate the impact on yarn hairiness. The influences of some important parameters including the yarn twist factor, the embedded fiber length, the frictional coefficients, and the size of the cheese are examined.
Yarn Pull-Out as a Mechanism for Dissipating Ballistic Impact Energy in Kevlar® KM-2 Fabric
Authors: Kirkwood Keith M. , Kirkwood John E. , Young Sil Lee  , Egres Ronald G. , Wagner Norman J. , Wetzel Eric D.
Published: March 2008

Yarn pull-out can be an important energy absorption mechanism during the ballistic impact of woven Kevlar® fabric. This study reports the effects of fabric length, number of yarns pulled, arrangement of yarns, and transverse tension on the force-displacement curves for yam pull-out tests on Kevlar® KM-2 fabric under laboratory conditions. A semi-empirical model is presented for predicting the yam pull-out force and energy as a function of pull-out distance, including both yarn uncrimping and subsequent yam translation. This model is found to replicate the experimental data with a high degree of accuracy, and should prove useful for understanding ballistic experiments and improving computational modeling of fabrics.
Yarn Pull-Out as a Mechanism for Dissipating Ballistic Impact Energy in Kevlar® KM-2 Fabric
Authors: Kirkwood John E. , Kirkwood Keith M. , Lee Young Sil , Egres Ronald G. , Wagner Norman J. , Wetzel Eric D.
Published: March 2008

The energy absorbed in ballistic fabrics is modeled by assuming yarn pull-out, including yarn uncrimping and translation, as the primary energy absorption mechanism. Using a semi-empirical model of yarn pull-out based on laboratory tests, predictions of fabric ballistic performance are compared to ballistic test results. The study demonstrates that quasi-static pull-out results can be correlated quantitatively with yarn pull-out during ballistic impact.
New Generation of Liposomic Products with High Migration Properties
Authors: Martí M. , De La Maza A. , Parra J.L. , Coderch L. , Serra S.
Published: March 2008

The usefulness of liposomes made up of phosphatidylcholine for wool dyeing has already been demonstrated. The dyeing temperature can be 10°C lower than for conven tional dyeing, with similar dye exhaustion and lower environmental impacts. However, conventional liposomes do not favor dye migration and do not achieve good leveling without synthetic auxiliaries. This work presents new strategic liposome formulations to increase migration phenomena in wool fabrics and yarn dyeing. The promising results obtained with these specific liposome formulations are compared with those using a number of commercial migrators such as Tanapal LM and Albegal SET in wool fabric dyeing with premetallized 2:1 (Lanaset) and 1:1 (Neolan) dyes.
Moisture Management Properties of Heat-Resistant Workwear Fabrics— Effects of Hydrophilic Finishes and Hygroscopic Fiber Blends
Authors: Yoo Shinjung , Barker Roger L.
Published: March 2008

This study examines the liquid moisture transfer properties of a selected group of heat-resistant workwear fabrics using a demand wettability test. The Gravimetric Absorbent Testing System procedure is modified and developed to assess the effects of wicking finish treatment and hygroscopic fibers on workwear fabrics. Unlike the simple vertical method of measuring wicking, the procedure adopted in this study produces informative results for moisture management characteristics and wearer comfort of textile materials. The absorption capacity, instantaneous rate of absorption, and evaporation/absorption ratio of five different heat-resistant workwear fabrics are determined and discussed. Results show that the wicking treatment of aramid fabrics noticeably increases their rate of absorption but does not affect their absorption capacity and water vapor absorption. The flame resistant rayon blends have improved vapor absorption properties but adversely affected liquid moisture management properties. Since the cotton fabric shows the highest percentage of remaining water after the evaporation test, a garment made of this fabric may generate a clammy feeling despite its superior absorbent capacity and rate of absorption.
Objective Evaluation of Fabric Pilling Using Stereovision
Authors: Kang Tae Jin , Cho Dae Hwan , Kim Sung Min
Published: March 2008

A noncontact three-dimensional measurement method for the objective evaluation of fabric pilling is developed. Three parameters, including the number, area, and density of pills, are defined by analyzing the five conventional standard pilling photographs that characterize pilling. The relationship between pilling grades and those three parameters can be obtained through a multivariable linear regression method. A CCD camera is used to capture the image of a laser line projected on the surface of the fabric specimen, and a simple trigonometric calculation is performed to reconstruct the three-dimensional shape of the fabric. Also, two CCD cameras are used to reconstruct the fabric surface with pills with a stereovision technique. The three-dimensional surface model is transformed into a binary image using a height-threshold algorithm, and the parameters extracted from that image are used to calculate the pilling grade of the specimen.
Evenness in Two-End Loads of Padders by Genetic-Based Self-Tuning Fuzzy Control
Authors: Huang Chang-Chiun , Yu Wen-Hong
Published: March 2008

This paper presents an experimental study of self-tuning fuzzy control of the two-end loads of padders. A simplified padder set-up is used. In conventional fuzzy control, membership functions and control rules are designed based on human subjective criteria, so very often, the design attempt may not lead to excellent performance. Our membership functions and control rules for load control of padders are experimentally investigated in this application. However, the ability to maintain two-end loads at the desired values is not satisfactory. To improve performance, membership functions are tuned based on an optimization technique of genetic algorithms to yield self-tuning fuzzy control. The experimental results indicate that the self-tuning fuzzy controller can maintain the two-end loads not only evenly and at the desired values. The tuning scheme is helpful in eliminating time-consuming trial-and-error procedures when refining membership func tions or control rules.
A Model for Predicting a Yarn's Knittability
Authors: Döonmez S. , Marmarali A.
Published: March 2008

In this study, we attempt to determine the knittability of a yarn before knitting. Thirty different yarns are knitted into 1 × 1 rib structures with three different loop length values. The knitting process is observed and the number of machine stops, yarn breaks, and holes are recorded. The results of experiments are evaluated by charts and statistical analyses. With a multiple regression analysis, two equations that depend on yarns characteristics can be used to predict yarn-needle and yarn-yarn friction values. In the last stage, we use a binary logistic regression analysis to indicate knittability, depending on the yarn-needle and yarn-yarn friction values, the machine tightness factor, and machine speed values.
Tactile Feeling: Sensory Analysis Applied to Textile Goods
Authors: Philippe Flora , Schacher Laurence , Adolphe Dominique C. , Dacremont Catherine
Published: March 2008

Descriptive analysis is one of the methods used in the food industry to describe the perception of products when being eaten. This work attempts to adapt this method to the description of fabric handle. A panel of eleven assessors use fifteen discriminant and pertinent attributes, and the assessors are trained to evaluate each attribute and to score them on a linear scale. The performance of each panelist is checked for validity and reproducibility before the panel is acknowledged as operative. Through implementation of rigorous procedures (i.e., exploratory procedures, sample presentation, and data analyses), this methodology provides reliable descriptions of the perceived quality of fabrics. The hand of the same cotton fabric treated with different industrial finishes is described by the panel. Results are analyzed in term of differences and similarities between the fabrics, sustaining commercial claims but in a more precise way. Finally, the fabric ranking from crease recovery tests agrees with the ranking of the panel on the responsive scale.
Effect of Bending Rigidity on the Capstan Equation
Authors: Jung Jae Ho , Kang Tae Jin , Youn Jae Ryoun
Published: March 2008

A tensioned fiber or yam in contact with a circular body is analyzed. In the model, a fiber is considered as a linear elastic and inextensible beam. An exact mathematical model is derived and the analytical solution is obtained. Both the beam-body contact and two noncontact regions are analyzed. From the equilibrium equation of force and bending moment, the derived model has three compatible ordinary differential equations, and one algebraic equation from the Euler beam theory with four unknown parameters. From the solutions, the relationship between incoming and outgoing tension is obtained, and we call this the modified capstan equation. The results show the correction connecting the capstan equation and its applications. For example, in a typical case, the capstan equation underestimates the effect of bending rigidity, which renders the only physically possible situation of tension in a real capstan to be the equilibrium of inclined tension. Moreover, the sensitivity of the tension ratio on the variation of the inclined angle is extensive. For instance, the difference in the tension ratio between the classical and modified results may be the maximum 71% value for a mere 100 variation of the inclined angle direction. Also, it is directly applicable to fiber contact with a body whose surface has a noncircular convex profile. Several further topics are suggested for discussion.
Minimizing Energy Consumption of Yarn Winding in Ring Spinning
Authors: Tang Zheng-Xue , Wang Xungai , Fraser Barrie
Published: March 2008

Ring spinning has been and will continue to be an important system for making staple yarns from different fibers in the textile industry. But high power consumption and low productivity remain the two outstanding problems with ring spinning. Based on an analysis of power distribution during yarn winding in ring spinning, models for the ratio of energy consumption to yarn production over a full yarn package are established. Spindle speed, yarn count, and package diameter are the three key parameters affecting this ratio. The effects on energy consumption of these parameters are discussed through a case study. The energy-to-production ratio increases with increased package diameter but decreases with increased spindle speed and/or yarn count (tex). The results will help guide spinners in minimizing energy consumption in ring spinning.
Refractive Indices of Textile Fibres: Double Variation Method for the Determination of
Authors: Fox Kenneth R.
Published: March 2008

It has long been the opinion of many textile technolo gists that some precise and easily duplicated means of determining the index of refraction would be of paramount value in investigating the structure of textile fibres as well as assisting in their positive identification. Such other phenomena as the effect of moisture content, the effect of strain or the so-called "memory" of plastics (such as silk, wool, rayons, etc.) , the identification of faulty yarn due to excessive tension or other orientation of structure,† the effect of mercerization, the correlation of index values with the quality of wool or the grade of cotton—all offer fields of study in fibre research provided that a precise means of refractive index determination is possible. It was with these problems in mind that the present work was begun on a more precise and convenient method of measuring the refractive indices of individual textile fibres.
The Moisture Regain of Acetylated Silk Fibroin
Authors: Carr Edward
Published: March 2008

Moisture regain measurements have been made at 25° C. and 79.3% relative humidity on non-acetylated and acetylated fibroin.

The equilibrium moisture content of acetylated fibroin is slightly lower than that of non-acetylated fibroin and varies with the degree of acetylation.

In the case of fibres acetylated by the action of acetic anhydride it is shown that the decrease in moisture content is not attributable to the action of liberated acetic acid.
A Tube for Studying Dilute Sediments
Authors: Beavers Ellington M.
Published: March 2008

1. The Kelly tube involves an error because of drainage from the side-arm into the main tube, as pointed out by Duncombe and Withrow.

2. It has been shown that this becomes negligible by re- designing the tube.

3. A general equation has been derived which permits direct calculation of the percent settled and which does not require that the density of the particle or the concentration of the suspension be known.

4. Experimental results are given for the settling of a BASO4 suspension.
Viscose Rayon: Stress-Strain Properties
Authors: Bellinson H.R.
Published: March 2008

This is the first report in an investigation of the effects of testing conditions on the load-stretch properties of viscose rayon. This report discusses the effect of chang ing specimen length.

It is found that increase in length results in a de crease in the breaking strength. The magnitude of the decrease is in good agreement with Peirce's theory of the Weakest Link.

Increase in specimen length also produces an apparent decrease in the per cent breaking stretch. This is prob ably the result of a jaw effect, in that some extension of the portion of yarn gripped by the jaws may occur.
Viscose Rayon: Stress-Strain Properties
Authors: Bellinson H.R.
Published: March 2008

The effect of varying the rate of load upon the strength, breaking stretch and load-stretch diagram of viscose yarn is described. Tests were made on an in clined-plane machine, in which the rate of increase of load is constant throughout any one test'.

The strength increases as the rate of loading is in creased.

S = 2.3R + K

where S is the breaking strength at rate of load R, and K is related to the inherent strength of the material. The breaking stretch appears to be unaffected by change in rate of load. The only portion of the load diagram which appears to be definitely affected by the rate of load at which the test is performed is the "elastic limit," which increases with the rate of loading.

1. Bellinson, H. R. Text. Rsch., May, 1940, P. 287-97.

2. Tippett, L. H. C. "The Methods of Statistics," Williams and Norgate (1937), p. 126.

3. Tippett. Ibid., p. 164.

4. Tippett. Ibid., p. 149.

5. Tippett. Ibid., p. 186.

6. Haven, G. B. Proc. Am. Soc. Test. Mats., 23, 653 (1923). 7. Schoffstall, C. W. and Hamm, H. A. N. B. S. J. Rsch., 2, 871 (1929). 8. Hunter, A. S. Rayon Text. Mo., 17, 739, 805 (1936). 9. Steinberger, R. L. Text. Rsch., 4, 229 (1934).
Behavior of Gelatins and Glues in Size Baths at Low Concentrations
Authors: Yelland William E.
Published: March 2008

During a study of the slashing of rayon warps for pile fabrics size mixes which contained less than 1% size material were used. Under these circumstances it was observed that the amount of size deposited on the yarn and the resultant weaving efficiency of the warp were af fected not only by the concentration of material in the size mix but also by the viscosity of the size bath. When used at the same concentration, materials of higher gel strength produced size baths with higher viscosity and deposited more size on the yarn than materials of lower gel strength. When the concentrations were adjusted so as to produce size baths with the same viscosity, the size absorption was related to the concentration. The weaving efficiency, al though not directly proportional to the amount of size on the yarn, was appreciably affected by changes in the amount of size absorbed.

Changes in the temperature of the size bath led to variations in size viscosity. These produced fluctuations in size absorption and were followed by changes in weav ing efficiency. At these low concentrations no differences in size distribution on the yarn were observed.
Electrodialytic Estimation of Ash and of Acidic and Basic Groups in Textile Fibres
Authors: Sookne Arnold M. , Fugitt Charles H. , Steinhardt Jacinto
Published: March 2008

Considerable practical interest attaches to the ash of textile fibres. It is well known, for example, that the electrical properties of textiles such as cotton, silk, and wool depend to a considerable extent upon the nature and amount of inorganic substances in the fibres. In addition, this ash content influences the uptake of mois ture and dyestuffs, as well as the ability of the fibre to combine with certain softening or finishing agents.

The method of combustion usually employed for the estimation of the ash yields results which acquire significance in terms of equivalents only when an estimate of the composition of the ash can be made. Since the ash may contain substances, such as sulfate in the case of wool, which are not in the unburned fibre, but which are formed during the combustion process, its composition is un certain at best.

It is shown by recent work of the research associates of the Textile Foundation at the National Bureau of Standards that the hydrogen-ion equivalence of the cationic ash of fibres (the total content of the cations of bases whether free, or combined with acids, or with the acid groups of the fibres) may be obtained di rectly, without ignition, by existing electrodialytic procedures which hace been hitherto applied principally to biological solutions. Only simple and inexpensive equipment is required. The content of any given anion in the sample may be similarly determined. By dupli cating the procedure on a larger scale, the method has been used to obtain samples of fibrous materials of very low ash content. A simple extension of the method which permits the quantitative de termination of the acidic and basic groups in the material consists in combining them with suitable tightly bound cations or anions which are subsequently estimated by the electrodialytic procedure.

Examples are given of the application of the method to de waxed and to depectinized cotton. In both cases the results are shown to correspond with the capacity of the fibres to bind acid. Examples are also given of ash determinations on wool fibres and on samples of wool cloth at several stages in processing subsequent to the carbonizing process. A comparison of the results with the ash obtained gravimetrically on similar samples, after combustion, permits the estimation of the average equivalent weight of the constituents of the ash, and aids in their identification. It is shown that the largest part of the ash of untreated wool, as ob tained by combustion, consists of sulfates. Since sulfates are not present to an appreciable extent in washed (defatted) root-wool fibres, the presence of this anion in the ash of such fibres must be attributed to the oxidation of the sulfur of the wool during com bustion. The much larger ash remaining after carbonizing, neu tralizing, and rinsing is also in the form of sulfates, but at these stages most of the sulfate has been contributed by the sulfuric acid in the carbinizing process.
The Relation of Cation Exchange to the Acidic Properties of Cotton
Authors: Sookne Arnold M. , Harris Milton
Published: March 2008

It has long been known that cellulosic materials exhibit acidic properties which influence many of their physical and chemical characteristics. Thus, the acidic groups of the fibre bind small amounts of ash which have a considerable effect on the electrical conductivity of cotton fibres, and on the viscosities of solutions of some cellulose derivatives. The ash may also affect the dyeing properties of the fibre, and may be related to the application of finishing agents. Since the ash of washed cotton consists prin cipally of cations held by acidic groups, the problems of measuring the ash and the number of acidic groups on the fibre are intimately related. In addition, if some of the acidic groups of purified cot ton are a part of the cellulose molecule, such as end-groups, the number of these groups may be a measure of its chain length, which is of primary importance in determining the strength and other physical characteristics of the fibre.

As part of a general program for the investigation of the acidic and basic properties of textile fibres, a study has been made of the manner in which hydrochloric acid is bound by cotton, and of the dependence of the amount of acid bound on the concentration of the aoid solution in contact with the fibre. The effect on this dependence of different amounts of an added neutral salt, potas sium chloride, has also been studied.

A comparison of the acid bound with the cationic ash (the total content of the cations of inorganic bases) as determined by an electrodialysis method leads to the conclusion that the maximum acid-binding capacity is equivalent to the cationic ash, and that therefore the acid bound at any acidity depends upon the ash. A comparison of the results for dewaxed cotton with those for de pectinized cotton shows that most of the acidic groups of cotton are contributed by the pectic substance.

Cotton freed of pectic substance retains a small number of acidic groups. Although other possibilities exist, it seems likely that these are an integral part of the cellulose molecule, such as an end-group. If this is actually the case, the results show that the cotton cellulose ~rnolecule has an equ.ivatent weight of about 100,000 which corresponds to a minimum chain length of about 600 glucose residues.
Determination of Regain of Sized Rayon Warps: Checking the Efficiency of One Type of Warp Conditioner
Authors: Yelland William E.
Published: March 2008

A method is given for determination of the regain of entire warps immediately after slashing on the silk system. This method obviates the necessity of taking samples either from the warp dur ing slashing or from the end of the warp immediately after sizing. The necessary samples can be obtained when the warp has woven in the loom as far as a convenient cut-mark.

The purpose of this set of experiments was to determine whether or not a warp conditioner installed at the front of the slasher was actually bringing the regain of the warps up to the desired value. In this case it was found that the capacity of the conditioner was much too small. Consequently it was merely cooling the warps and not conditioning them, and the warps were leaving the slasher with regains from 1 to 7%.
Pectic Substance of Cotton Fibres in Relation to Growth
Authors: Whistler Roy L. , Martin Albert R. , Conrad Carl M.
Published: March 2008

The content of pectic substance in cotton fibres at various stages of growth was determined. The results suggest three distinct stages of de velopment of the fibre. The first extends to about the 18th day and is char acterized by a gradual decrease in the content of pectic substance. The second extends from the 18th to about the 35th day during which time there occurs a rapid decrease in the content of pectic substance. In the final stage, which extends from about the 35th day to maturity, there is only a slight decrease in the content of pectic substance. These three stages of de velopment are in good agreement with those deduced by other investigators from different types of data.
The Variation of Raw Cotton Con stituents with Physical Properties
Authors: Nickerson R.F. , Fontaine T.D. , Leape C.B.
Published: March 2008

On the basis of a limited number of samples there appear to be correlations between the relative surface areas of cottons and wax and pectate contents, between fineness and nitrogen content and, possibly also, between fineness and alkalinity of ash. A large number of analyses on different cottons will be required to show the exact relationships.
Microscopic Structure of the Cotton Fiber
Authors: Hock Charles W. , Ramsay Robert C. , Harris Milton
Published: March 2008

During the examination of cotton fibers that had received vari ous chemical treatments, a number of observations pertaining to the structural details of the fiber were made. Those phenomena which appeared to be new were investigated in detail. In addition, experiments described by earlier investigators were repeated in order to have a better composite picture of the structure of the fiber.

The cell wall of a cotton fiber consists of a primary and a sec ondary wall. The latter, which comprises the bulk of the fiber, con sists of innumerable spirally oriented cellulose fibrils enclosed by a winding which also makes a spiral, but in the opposite direction from the former. Both the winding and the fibrils reverse their direction at frequent intervals along the axis of the fiber, their points of reversal being coincident. The secondary wall is en closed by a thin primary wall. The latter is made up of fine criss crossing strands of cellulose embedded in a membrane consisting principally of wax and pectic substance. The lumen also contains wax and pectic materials, plus various amounts of degenerated pro toplasm.

When cotton fibers are swollen under certain conditions a lamel late structure is discernible in the secondary wall. The number of these lamellae increases with the age of the fiber.

On treatment of cotton fibers with cuprammonium hydroxide reagent, the cellulose dissolves, leaving residues which vary in amount and in structure, depending upon the extent of purification of the fibers. The residue from raw and from dewaxed fibers con sists of fragments of the primary wall, and of a lesser amount of material from the lumen. The behavior of the fibers in the reagent depends in part on their maturity. Immature fibers containing only small amounts of cellulose swell relatively little in the reagent and the undissolved wax and pectic materials maintain the original tubular shape of the primary wall. When older fibers are given the same treatment they swell abruptly, thereby causing the primary wall to break in many places, giving rise to "balloons."

Irregular swelling along the fiber axis, which results in the formation of balloons, appears to be dependent in part on the orien tation of the fibrils, and in part on the constricting influences of the winding and of the primary wall.
Base-Combining Capacity of Cotton
Authors: Sookne Arnold M. , Harris Milton
Published: March 2008

It is well recognized that cellulosic materials contain acidic groups which bind ions and accordingly influence the electrical conductivity, the dyeing, and the finishing of the fibers or fabrics.

In an earlier investigation, the relationship between the ash content of cotton fibers and their acid-binding capacity was devel oped. To study further the acidic properties of cotton, the investi gation has now been extended to include the direct estimation of the acidic groups in the fiber by titration with alkali. Both mono valent and divalent cations were used in this work.

When dewaxed cotton is freed of its cationic ash electrodialyti cally, it binds a maximum of 0.065 milliequivalent per g. of either silver or calcium ions, while depectinized cotton binds only 0.010 milliequivalent per g. These values confirm previous estimates of the carboxyl contents of these samples obtained by titration with acid. The identity of the base-binding capacities when mono- and divalent ions are used is a strong indication that the binding of these ions results from an acid-base reaction rather than from some undefined adsorption process. This conclusion was substantiated by esterifying the acid groups of eelctrodialyzed depectinized cot ton with diazomethane, which thus reduced the base-binding ca pacity to nearly zero.

It is shown that the maximum silver-binding capacity can be obtained only by the use of the silver salt of a very weak acid. When the salt of a strong acid is used a sufficient number of hy drogen ions are in the solution to compete with the silver ions for the acidic groups of the fiber.

The silver-binding capacities of electrodialyzed dewaxed and electrodialyzed depectinized cotton are greater than those of de waxed and depectinized samples, respectively. This result is ex plained in terms of competition of silver ions with the cations already on the acidic groups of the fiber.

The number of acidic groups in depectinized cotton is not altered by progressive treatment of the fiber with alkali, a fact which lends support to the tentative conclusion that the acidic groups in depectinized cotton are an integral part of the cellulose molecule.