Showing papers in "Textile Research Journal in 1950"

"Orlon" Acrylic Fiber: Chemistry and Properties

Abstract: 2. Anderson, S. L., Cavaney, B., Foster, G. A. R., and Womersley, J. R., J. Text. Inst. 36, T253 (1945). 3. Elting, J. P., and Barnes, J. C., TEXTILE RESEARCH JOURNAL 20, 773 (1950) (this issue). 4. Johannsen, O., Kleipzigs Textil-Z. 41, 369 (1938). 5. Saxl. I. J., J. Text. Inst. 26, T77 (1935). 6. Stanbury, G. R., J. Text. Inst. 22, T385 (1931). 7. Vose, R. W., and Plummer, C. H., J. Text. Inst. 36, T177 (1945). 8. Whitehead, W. and J., Ltd., Steward, O. M., and Smith, E. P., B. P: 343,215 (Dec. 4. 1929).

Mechanics of Elastic Performance of Textile Materials: Part VI: Influence of Yarn Twist on Modulus of Elasticity

Abstract: T HE RECENT LITERATURE on textile research has indicated a growing interest in the modulus of elasticity of fibers and yarns. In addition to its importance as a basic property of fibers [ 1 ] , offering clues to the molecular structure [5] ] and also changes therein produced by chemical treatments and/or processing, the numerical value of the modulus of elasticity serves as a constant which enters into the solution of many applied problems concerned with mechanical performance [2]. Hamburger [1] and Maginnis [2] have provided data on the modulus of elasticity of a series of yarns within which the yarn twist was systematically varied. It was found that as the yarn twist increased the modulus decreased uniformly, in what visually appears to be a parabolic variation. In a series of papers [4] concerned with the influence of yarn geometry on translation of fiber properties, the present writer employed methods of stress analysis to develop formulas which allow for the prediction of yarn properties once fiber properties and yarn geometry are specified. The present paper shows that these formulas and methods are applicable to the explanation of changes in modulus with changes in twist, and, therefore, to their prediction. Free use will be made of the data already reported by Hamburger [1] ] and Maginnis [2]. Both the dynamic and the static modulus will be considered.

Mechanics of Elastic Performance of Textile Materials: Part V: A Study of the Factors Affecting the Drape of Fabrics—The Development of a Drape Meter

Abstract: is said to have good draping qualities when the configuration is pleasing to the eye. Obviously, then, the word &dquo;drape&dquo; is a qualitative term. The textile industry realizes the importance of understanding the phenomenon of drape and is anxious to be able to measure it quantitatively. Numerous &dquo;drape tests&dquo; have been reported in the literature, but none have presented any correlation between the data obtained and subjective evaluations. This is largely because of the failure to realize that drape may not be determined conclusively by those tests which involve two-dimensional distortions of the fabric samples. (These

Mechanics of Elastic Performance of Textile Materials III. Some Aspects of Stress Analysis of Textile Structures— Continuous-Filament Yarns

Abstract: Stress-analysis methods for textile materials are illustrated through a study of the forces pro duced when a continuous-filament yarn is stressed in tension It is shown that the effects of yarn twist and yarn size on the tensile properties of singles continuous-filament yarns depend upon the stress distribution Mathematical formulas are derived to express variations in tensile character istics, both for one-time loading to rupture and repeated stress, as a function of yarn geometry The influence of fiber inherent properties is described and illustrated by experimental data ob tained for viscose rayon, acetate rayon, and nylon of various singles geometry

Crystallinity of Cellulose and Its Significance for the Fiber Properties

Abstract: The subject of this paper is treated mainly from the standpoint of cotton cellulose. The concept of crystallinity is discussed not simply in the narrow sense of degree of crystallinity but in the b...

Studies on the Microbiological Degradation of Wool Digestion of Normal and Modified Fibrillar Proteins

Abstract: Measurements of the susceptibility of various keratins and fibrillar proteins to digestion by a keratinolytic fungus were made. Both normal and modified proteins were used. Digestion of the following fibrillar proteins by Microsporum gypseum over a 21-day period was, from the highest percentage digestion to the lowest: collagen, feather, hoof, wool, horn, horsehair, mohair, and silk.The primary factors which determine the rate of digestion of fibrillar proteins were found to be the chemical composition and the molecular architecture. In keratins, the degree of poly merization assumes the greatest importance. The higher the degree of polymerization, pri marily attributed to the disulfide cross-linkages, the more resistant the keratin is to enzymic digestion. Histological complexity of keratinaceous tissues and geometrical structure of the keratin molecule do not influence the rate significantly.

Ion-Exchange Characteristics of Chemically Modified Cotton Fabrics:

Abstract: A method is described for comparing microscopically the cross-sectional areas of the same cotton fiber in wet and dry conditions, for evaluation of swelling. Results indicate the change in cross-sectional area of raw cotton fibers to be between 21 % and 34% of the dry area regardless of variety of cotton or degree of maturity of the fiber. Immature samples show slightly less mean swelling than mature samples, but this is believed to be due to the presence of fibers with no secondary thickening at all which tend to shrink in cross-sectional area rather than swell. In the immature fibers deformation (defined as change in circularity) is slightly more than that of mature fibers. This, coupled with the fact that in a given weight of immature fibers there are approximately twice as many fibers as in a like weight of mature fibers, helps to explain the greater closing capacity of yarns made from immature cotton. Flax and a sample of viscose rayon show twice the swelling of cotton, Fortisan two-thirds as much, and nylon no crosssectional swelling at all.

Ultrasonic Disintegration of Cellulose Fibers Before and After Acid Hydrolysis

Abstract: THE EFFECT of ultrasonic vibrations on both native and regenerated cellulose fibers is to break them down into thin, almost electron optically transparent &dquo;fibrils,&dquo; the length and width of which depend upon the type of fiber. However, if the fiber is subjected first to acid hydrolysis followed by ultrasonic vibration, then &dquo;particles&dquo; instead of fibrils are obtained. The size and shape of these hydrolyzed cellulose particles are of two types, depending upon whether they originate from native or from regenerated fibers. It is the purpose of the present paper to show that the particle dimensions, which can be

Creasing and Creaseproofing of Textiles

Abstract: within the fibers. For cellulosic fabrics, with which this paper is mainly concerned, the exact inter-relations among these various factors have not as yet been quantitatively determined. Nevertheless, considerable data have been presented in the literature dealing with some general principles related to the crease-resistance of textiles and to the industrial processes for producing crease-resistant rayon and cotton fabrics. For a complete and informative summary of this subject, the reader is referred to the recently published article by Buck and McCord [1]. In this present discussion, we should like to examine and to provide answers to some particular questions related to the creasing and creaseproofing of fabrics made of regenerated and native cellulose fibers. These are:

A Quantitative Study of Resilience

Abstract: us entitled &dquo;A Generalized Concept of Resilience&dquo; ~ 1 ~ , it will be helpful to recapitulate the main points of the earlier publication. First, it was pointed out that the term &dquo;resilience&dquo; has many different meanings, the meaning in a particular instance depending upon the speaker (or writer) and the context. munch of this confusion is removed if we recognize that resilience has two aspects-namely, type and extent. Each of these aspects has its own complex factors, and, although neither one can be measured entirely independently of the other, the two should be regarded as separate entities. It was next shown that type of resilience is separable into two factors, each of which is complex and measurable by various means. One of these factors

Mechanical Properties and the Structure of Hair

Abstract: A simple quantitative method for determining the amount of mechanical strength contributed by the various types of bonds in hair fiber has been developed. The effects of various types of reagents, ...

Law of Critical Yarn Diameter and Twist Influence on Yarn Characteristics

Abstract: The effect of increased twist upon yarn density is explored and a law of critical diameter is postulated. It is suggested that at the time at which a yarn breaks under tensile load the density of t...

Air Porosity of Open-Weave Fabrics* Part I: Metallic Meshes

Abstract: A method is proposed which has been experimentally verified for analyzing porosity‡ data in terms of two dimensionless parameters—the discharge coefficient and Reynolds number—char— acterizing the flow through interyarn pores of a metallic fabric. It is experimentally shown that porosity data for wire screens ranging in texture from 8 to 120 wires per in. and in porosities from 30 to 680 ft.3/ft.2, min. can be plotted within rather narrow limits as a single line relating the two dimensionless flow coefficients.

The Sub-Cuticle Membrane—A Recently Discovered Morphological Component of the Wool Fiber:

Abstract: made using data obtained by the use of an arealometer and by the usual mechanical weight-per-inch methods, and it has been brought out that genetic differences in perimeter exist in cottons [ 1 ]. Perimeter and surface area per unit weight are, therefore, not equivalent terms and are not related to one another by any fixed proportionality constant. If one follows Dr. Hevn when he states (p. 711), &dquo;The assumption was made that the amount of wax in the primary wall is proportional to the wall sur-

The Swelling of Cotton in Water: A Microscopical Study

Abstract: A method is described for comparing microscopically the cross-sectional areas of the same cotton fiber in wet and dry conditions, for evaluation of swelling. Results indicate the change in cross-se...

Measurement and Theory of Absorbency of Cotton Fabrics

Abstract: High and uniform absorbency of cotton fabrics is a desirable quality in nearly every wet- finishing operation and in many finished fabrics; yet absorbency-measuring tests which have been employed u

Measurement of Friction Between Single Fibers: V. Frictional Properties of Viscose Rayon Staple Fibers

Abstract: In a previous communication by Gralén and Olofsson [2~ a description was given of a new apparatus for the measurement of single-fiber friction, its construction, and theory. Some preliminary results were also given. In the case of wool fibers a very great dispersion of the separate readings was found, as regards antiscale friction. The reason for this is that relatively small differences in the height and the shape of the scales can give rise to rather large differences in friction. Smooth fibers give less dispersion of the values. Using the stick-slip apparatus is more time-consuming and laborious than using the twist friction meter described by Lindberg and Gralen [6], but in other respects the former has some advantages over the latter apparatus. Firstly, the distribution of the load on the contact surface is

Mechanics of Elastic Performance of Textile Materials: Part IV: Some Aspects of Stress Analysis of Textile Structures—Staple—Fiber Yarns

Abstract: The study of the influence of textile geometry upon textile structure performance is extended to staple-fiber yarns. Methods previously developed for continuous-filament yarns [6] are applied to de...

The Kinetics of Wool Dyeing Part I: Simple Acid Dyes

Abstract: It is shown that the rate controlling mechanism of dyeing wool with the simple acid dye Acid Orange II can be diffusion through an unstirred film of liquid or diffusion through the fiber. At low concentrations of dye, the diffusion of dye through an unstirred film of liquid is the slower of the two processes, whatever the degree of agitation. At higher concentrations of dye, the rate controlling step changes from diffusion through liquid film to diffusion through solid when the stirring of the solution is increased beyond the point at which the reaction becomes stirring- independent and the activation energy, determined from the temperature coefficient, changes from approximately 5 to 13 kg.-cal./mole.At high concentrations of dye the diffusion of dye through the fiber proceeds from a saturated concentration on the fiber surface, which action can be readily treated quantitatively. At low dye concentrations the diffusion through the unstirred liquid film can also be treated by the simple diffusion law. In ...

The Measurement of Fabric Wrinkling

Abstract: method of analyzing fabrics which have been deformed by the random type of wrinkling which occurs under service conditions. In some respects, it resembles the Brush Surface Analyzer, the Physicists Research Company’s &dquo;Profilometer,&dquo; and other instruments which measure surface contours. The purpose of this paper is to describe the instrument, which we have named the &dquo;Wrinklometer,&dquo; and to indicate its performance and potentialities.

Degradation of Cellulose as Revealed Microscopically

Abstract: Because natural cellulose is fundamentally fibrous, degradation—be it caused by chemical agents such as acids and alkalies, by physical agents such as grinding and ultrasonic vibration, or by biological agents such as molds and bacteria—proceeds in a manner which reflects this basic fibrillate structure. The dimensions of the threadlike fibrils into which cellulose breaks down vary, depending upon the severity of the treatment and perhaps also on innate differences among celluloses from various sources. Following degradative action, light microscopy reveals fibrils of the order of several tenths of a micron in diameter. At the higher magnifications obtainable with the electron microscope, still finer fibrils, a few hundred Angstroms wide, are detectable. Certain degradative treatments cause a further transverse splitting of these fibrils into rod-shaped structures.From x-ray and chemical investigations it is known that cellulose is made up of long-chain molecules whose arrangement with respect to one anot...

Microbiological degradation of cellulose.

Abstract: destructiveness of microorganisms which degrade cellulose, their control by chemicals, and the resistance of chemically modified cellulose to these agents has been obtained through this systematic inquiry. But no panacea against ultimate deterioration has been discovered. The more recent knowledge has been applied by manufacturers of textiles and finishes, and as a consequence the service life of these materials has been lengthened. The exact mechanism of microbiological attack on cellulose is not known, but various theories have been advanced. An attempt will be made to clarify some of our reasoning about this mechanism by reviewing

Effect of Crimp on Fiber Behavior Part II: Addition of Crimp to Wool Fibers and Its Effect on Fiber Properties

Abstract: The importance of crimp in natural wools is discussed. Wear and coverage of crimped vs. uncrimped materials are demonstrated. A method of crimping wool artificially is shown and production equipment is discussed schematically. Theoretical expressions are developed for stress-concentration effects and are compared with experimental results. A theory for the mechanics of the crimping operation is advanced.

A Simple Quantitative Test for the Felting of Wool Top

Abstract: A simple, rapid procedure for evaluating the feltability of wool in the form of top is pre sented. The method consists of subjecting a sliver to controlled wet mechanical action, and measuring its change in length. It yields results which correlate well with the shrinkage during laundering of garments made from the top; the method thus provides a useful tool for con trolling the application of some chemical shrink-resistant treatments in the mill. In addition, this method shows promise of usefulness as a tool for investigating the nature of felting.

Microbiological deterioration of cellulose during the first 72 hours of attack.

Abstract: The effects of microbiological attack on breaking strength of textiles have been studied in many laboratories. In most cases a great loss of strength was noted after 3 days of attack by molds. A preliminary study in this laboratory of the course of attack by 3 organisms during the first 72 hrs. indicated that the strength of cotton duck was reduced from 35% to 60% during this time, although there was no evidence of mycelium to the unaided eye. This project was undertaken to study further the profound changes which take place in cellulosic fibers due to the action of 5 cellulolytic molds during the first 72 hrs.

Conversion of the Saco-Lowell Sliver Tester to Electrical Recording:

Abstract: The theory and mechanics of converting a Saco-Lowell sliver tester from a graphic-recording instrument to one which records by means of electrical counters are described. General design of the equipment is discussed and photographs of the machine are included. Experience with the converted instrument since March, 1949, indicates that it provides a worth-while improvement in accuracy and in speed of analyzing the uniformity of sliver and heavy roving.

Measurement of Friction Between Single Fibers VI. A Theoretical Study of Fiber Friction

Abstract: 8. The electrical conductivity of rayon fibers is only slightly influenced by the application of spinning auxiliaries if the amount of auxiliary added is not very great. 9. A theoretical study of the influence of frictional properties on sliver movement in drawing frames was made. 10. The variation of frictional coefficients meaS7 ured on a bulk of fibers is always significantly higher than the variation of measurements on one fiber.

The Relaxation of Stress in Wool Fibers

Abstract: A study of the decay of tension of Columbia 56's wool fibers maintained at constant tem perature and extension has been carried out in water, in solutions of sodium bisulfite of various concentrations, and in neutral salt solutions.The experimental results obtained in water are similar although not identical to the results previously found by Speakman and Shah for human hair. The rapid stress decay of stretched wool which occurs when sodium bisulfite is added appears to be due to a chemical reaction involving the cystine linkages. The rate becomes independent of bisulfite concentration at sufficiently high concentrations. A much slower but unexpectedly large stress decay occurs in the presence of neutral salts such as sodium chloride.

Investigation on the Differences Between Physical Properties of Skin and Core in Viscose Rayon Using the Peeling-Off Method Suggested by Elöd

Abstract: 1. Barnes, R. B., and Burton, D. J., Ind. Eng. Chem. 35, 120-5 (1943). 2. Battista, O. A., Ind. Eng. Chem., Anal. Ed. 16, 351-4 (1944). 3. Battista, O. A., Ind. Eng. Chem. 42, 502-7 (1950). 4. Cravath, A. M., Smith, A. E., Vinograd, J. R., and Wilson, J. N., J. Applied Phys. 17, 309-10 (1946). 5. Hermans, P. H., TEXTILE RESEARCH JOURNAL 16, 545-55 (Nov. 1946). 6. Howsmon, J. A., TEXTILE RESEARCH JOURNAL 19, 152-62 (Mar. 1949). 7. Huseman, E., Cellulosechemie 22, 132-5 (1944). 8. Kinsinger, W. G., and Hock, C. W., Ind. Eng. Chem. 40, 1711 (1948). 9. Mark, H., J. Phys. Chem. 44, 764 (1940). 10. Nickerson, R. F., and Habrle, J. A., Ind. Eng. Chem. 33, 1022 (1941) ; 34, 85 (1942); 34, 1 80 (1942). 11. Sears, G. R., and Kregel, E. A., Paper Trade J. 114, 43-9 (1942). 12. Williams, R. C., and Wyckoff, R. W. C., J. Applied Phys. 17, 23-33 (1946). 13. Wuhrman, K., Heuberger, A., and Mühlethaler, K., Experientia 2, 105-7 (1946).

Submicroscopic Structure of Cellulose from Nitrogen-Sorption Measurements

Abstract: When cotton linters were soaked in cold 10% sodium hydroxide, washed and neutralized, transferred successively to methyl alcohol and benzene, and carefully dried at reduced pressure, a surface area as great as 71.3 sq. m. per g. was obtained by the Brunauer-Emmett-Teller tech nique. Previously obtained areas for untreated cotton were all less than 1 sq. m. per g. Linters carried through the above steps after soaking in water instead of in alkali had areas as great as 47.3 sq. m. per g. When the alkali-treated sample was conditioned in water vapor to a 3.3% gain in weight, the surface decreased to 31.6 sq. m. per g.; further conditioning to an 11.0% gain in weight decreased the surface to 2.1 sq. m. per g.The isotherms of the treated samples showed strong hysteresis, while the isotherms of untreated cotton showed little or no hysteresis.Calculations of pore-size distribution by the method of Wheeler and Shull indicated that these materials have rather narrow distribution ranges, the alkali-treated material...