bluuebunny/crossref_metadata_2025 huggingface dataset:
Cotton—A Versatile Textile Fiber
Authors: Berkley Earl E.
Published: March 2008

Certain recent researches on cotton are reviewed, together with further data on natural variations of it as found on the cottonseed and modifications of the fiber by chemical and physical treatments. No attempt has been made to present a general review. A more extensive over-all treatment of cotton quality may be found in a report by the Bureau of Plant Industry [11].

Cotton fibers grow first in length, then in thickness. The physical properties of the fiber and, therefore, its use value are determined by its length, fineness, and cell-wall construc tion, all of which are genetically controlled but are also sub ject to modifications by weather conditions during growth. Since fiber length is established before the cell walls thicken, length and cell-wall structure may be influenced independ ently. As growth proceeds there is a general trend toward compensation of loss of fiber length by added strength and vice versa; however, the failure of weather conditions to remain the same throughout the growing period of the

fiber may result, for example, in short, weak fiber or long, strong fiber.

Cotton fibers may be modified by swelling treatments while tension is applied. Such treatments may increase the fiber strength at the expense of other properties.

The spinning quality of cotton is dependent upon a com bination of fiber properties and upon the spinning technique used. In general, however, the size of yarn or thread made from cotton is dependent upon its fiber length. For a given length, fiber fineness, and even strength, may influence the maximum count to be expected. Strong yarns require relatively strong fiber for any given fiber length and fineness. Uniformity of fiber length undoubtedly influences the ease of manufacture and the percentage of waste to be expected from a given cotton, but it is indicated that well-bred mod ern varieties have sufficient length uniformity to give good results. Within a variety, however, growth conditions, gin ning, and baling may affect the fiber-length uniformity enough to influence fiber property-yarn strength relationships. Since variety characteristics may be influenced by growth conditions, causing positive varietal relationships to reverse and become negative for environment, the analyses of data consisting of fiber properties and yarn strengths, except for very general treatments, will give more information if variety and environmental effects can be segregated. It is indicated that if good certified seed of suitable varie ties for each type of environment are planted, cotton of ac ceptable quality can be produced throughout the Cotton Belt. In selecting a cotton for specialized uses, variety and growth conditions as well as grade and staple should be considered for best results.
An Orifice Test to Evaluate Yarns for Swelling-Type Water-Resistant Fabrics
Authors: Smith Herbert O. , Murphy Alton L. , Goldthwait Charles F.
Published: March 2008

A technique is described for determining the relative closing capacities, largely a reflection of swelling behavior, of fibers in the form of parallel strands of yarn packed tightly in orifices, by observation of the seepage of water through the yarn. The method has been used successfully to predict the performance of cotton yarns for the type of water-resistant fabric whose utility depends largely upon "self-sealing" by swelling. Relatively wide variations in yarn construction have been shown to have little effect on closing capacity, whereas fiber shape and size, as well as swelling properties, have pronounced effects.
Effect of Grinding on the Crystallinity of Cellulose Fibers, as Indicated by the Acid-Hydrolysis and Other Techniques
Authors: Nelson Mary L. , Conrad Carl M.
Published: March 2008

A study was made of an effect previously noted, that grinding cotton fibers in a Wiley mill causes a reduction in degree of crystallinity as determined by the acid-hydrolysis method. It is shown on samples of purified linters and cut cotton, ground under conditions of increasing severity, that even mild grinding—for example, through a 2-mm. sieve—causes a detectable reduction in indicated degree of crystallinity, and that as the severity of grinding increases the degree of crystallinity drops correspondingly. This drop is not caused by passage of more of the finely ground particles from the more severely ground samples through the filters. When the ground samples were moistened with water and allowed to dry, a portion of the lost crystal linity was regained.

The acid-hydrolysis results are supported by accessibility, heat of wetting, and moisture adsorption measurements, which, with few exceptions, indicate increasingly larger amounts of amorphous material in the samples receiving the more severe grinding.

While the x-ray diffraction patterns did not reveal any effect of the most severe grinding, it is assumed that the changes were not sufficient to permit their detection by this means.

Some implications of the results on the interpretation of cellulose structure are discussed.
Structural Changes in Wool Degraded by the Ringworm Fungus Microsporum Gypseum and Other Microorganisms
Authors: Mandels G.R. , Stahl W.H. , Levinson H.S.
Published: March 2008

Observations in the literature concerning the effects of certain fungi and bacteria on the structure of the wool fiber are scattered and contradictory. In this study, using the fungus Microsporum gypseum and the bacterium Pseudomonas sp., it has been observed that the scale cells of the wool are not dissolved. On the basis of microscopic observations supplemented by breaking-strength determinations of degraded cloth and by loss in dry weight of degraded wool, it is concluded that the weakening of wool subjected to microbiological attack is due to effects upon the intercellular substance and upon the cortical cells. When degraded wool is wet, its breaking strength seems to be limited by the strength of the intercellular substance, whereas the tensile strength of such wool which has been dried apparently is determined by a weakening of the cortical cells. It has been demonstrated that the hyphae of M. gypseum penetrate the wool fibers and grow parallel to the fiber axis, apparently between the cortical cells. Presumably penetration occurs through the fiber ends or through breaks in the epithelium.
Compressional Behavior of Textile Materials
Authors: Finch Rogers B.
Published: March 2008

The description of an instrument to measure compressional stress-relaxation characteristics of textile materials at a constant compression, utilizing the sensitive response characteristics of a resistance-wire strain-gage cantilever weighbar, is given. It employs a deflection galvanom eter in conjunction with the strain gages in a D.C. Wheatstone bridge. Compression is applied instantaneously to the specimen and the semilog rate of stress relaxation is determined as a characteristic parameter of the behavior of the textile material.
Rheological Measurements with the Rotational Viscometer
Authors: Fischer Earl K. , Lindsley Charles H.
Published: March 2008

The rotating cylinder viscometer in various forms has found wide use for the measure ment of viscosity and the study of so-called anomalous flow. Starch pastes, pigment disper sions, printing pastes, and coatings are examples of materials used in the textile industry which exhibit complex flow properties. Identification of the different kinds of flow and measurement in terms of valid physical units are necessary before the properties of these materials can be correctly described. It can be expected that with adequate specification of flow properties more effective control in mill processes will become possible. This article is concerned with essential features of instrumentation, definition, and computation.
A Permeability Method for Determining Fiber Fineness
Authors: Elting John P. , Barnes James C.
Published: March 2008

An instrument to measure the air permeability of compressed fiber wads is described, together with essential details of construction. An index, F, of fiber fineness is defined follow ing the derivation of an approximate permeability. The roles played by porosity of the plug, the size, shape, and density of the fibers, and their effect on the values of F are discussed with reference to cotton. Errors due to sample weight, moisture, and trash are appraised. An estimate of the instrument precision is obtained by analysis of experimental data. The nature of results obtained from measurements on cotton is described; typical ranges of F observed for several varieties of cotton are noted.
An Electron-Microscopical Examination of Rayon
Authors: Hock Charles W.
Published: March 2008

By metallic shadow-casting of specimens for electron-microscopical examination, fibrils a few hundred Angstroms in diameter were demonstrated in cuprammonium and in viscose rayons. Fibrillation was more distinct in the rayons having a high degree of orientation. The fine fibrils in the fibers of both these regenerated celluloses were similar to those previously observed in native cellulose fibers.

A comparison of surface replicas of the fibers revealed distinct differences. Whereas the cuprammonium rayon fibers were relatively smooth except for occasional markings which gave them a scaly appearance, the viscose rayon fibers were rougher, and showed an irregular netlike pattern.
A Microscopical Technique for Determining Latex Distribution in Tire Cords
Authors: deGruy Ines V. , Rollins Mary L.
Published: March 2008

A dye-staining technique is described which permits the microscopist to locate the extent of penetration of latex in tire cords. Photomicrographs illustrate the results obtained.
Moisture Determination in Textiles by Electrical Meters: Part I
Authors: Toner Richard K. , Bowen Carol F. , Whitwell John C.
Published: March 2008

Results are reported from a study of two electrical moisture meters adaptable to bulk textile materials. Calibration curves at a single temperature are reported on white, scoured, wool yarns. Accuracy of the meters is dependent upon a calibration against an independent measurement of moisture. A modification of the loss-in-weight oven method was used as reference. Precision for both ovens and meters is based upon statistical analysis of groups of data. For instruments, in the best cases, the value was approximately 0.25 percent with the ovens at 0.40 percent moisture, both figures based upon two-sigma limits, sampling variance having been removed.
Some Aspects of the Photochemical Degradation of Nylon, Silk, and Viscose Rayon
Authors: Egerton G.S.
Published: March 2008

The vat dyes that are particularly effective in increasing the photochemical degradation of nylon, silk, and viscose rayon are capable of increasing the degradation of undyed cotton that is simultaneously irradiated in their vicinity. The experiments took the form of irradiating a sheet of yarn composed of alternate dyed and undyed threads not in contact with one another. The dyed threads used included nylon, silk, and viscose rayon yarns dyed with various vat dyes. Many of the dyed yarns have a considerable effect upon the degradation of adjacent undyed yarns of cotton or silk, but the same dyed yarns generally have only a small or negligible effect upon the degradation of undyed yarns of nylon or viscose rayon. These results are ap parently due to the greater resistance of the latter textile materials to oxidation by the volatile agent (hydrogen peroxide), which is responsible for the "action at a distance." In some cases- for example, dyed nylon-there is evidence that although the volatile agent is produced by the dye in a relatively large amount it is not responsible for the major proportion of the degradation of the dyed yarn. The effect of humidity on the rate of photochemical degradation of textile materials dyed with active vat dyes appears to be closely related to the ease with which the textile fiber is oxidized by the volatile agent.

These results are interpreted in terms of a theory in which the photochemical degradation of the textile material is represented as the result of oxidation by activated oxygen and/or hydrogen peroxide. The relative effectiveness of these two oxidation processes depends upon the particular experimental conditions and the nature of the textile fiber.
Degree of Polymerization, Spiral Structure, and Strength of Cotton Fiber
Authors: Hessler Lyle E. , Simpson Marion E. , Berkley Earl E.
Published: March 2008

Cotton fiber from bolls collected on opening and dried in the laboratory without exposure to direct sunlight were tested for the following fiber properties: fiber length, fineness, strength, spiral structure, and degree of polymerization (D.P.). When these individual properties were each correlated with the Pressley strength index in simple correlations, the spiral structure and Pressley strength index gave the highest r values, and the degree of polymerization and Pressley index the second highest. For variety effects, the D.P. and Pressley index gave a higher coefficient of correlation than the spiral structure and Pressley index. Significant r values were obtained between fineness and Pressley index for total and variety effects, between fineness and D.P. for all effects, and between spiral structure and D.P. for all effects. Further more, a significant r value was found when fiber length was correlated with chain length (D.P.) for total over-all effects. It is concluded that the length of the cellulose molecule (D.P.) is an important factor in the physical properties of cotton fibers. All multiple correlations, including the fiber properties used in the simple correlations, were highly significant for varieties within locations and for over-all effects. Spiral structure and chain length (D.P.) when correlated with Pressley strength gave the highest coefficient of correlation.
Continuous-Filament Casein Yarn
Authors: Peterson Robert F. , McDowell Robert L. , Hoover Sam R.
Published: March 2008

A process for producing continuous-filament casein yarn by pot-spinning is described. The fiber has a tensile strength of 1.0-1.2 grams per denier, elongation of 50 percent, excellent soft ness, and warmth. Fiber evaluation indices are presented.
A New Method of Sectioning Synthetic Fibers with the Ultra-Microtome for Examination with the Electron Microscope
Authors: Earle Marshall D. , Minkin Jean A.
Published: March 2008

A method has been devised in which a piece of rayon or nylon yarn, consisting of 10 or 20 single filaments, is prepared for sectioning with the high-speed ultra-microtome † in such a way that the boundaries of individual filaments can be identified when viewed in the electron micro scope. The yarn is mounted in a special holder in which the filaments are spread out radially. They are then coated with a thin film of evaporated gold in the vacuum unit. These filaments are allowed to fall parallel to each other again. They are embedded in a very thin layer of low- melting-point paraffin and sectioned with the ultra-microtome. The thin film of gold enables one to determine whether the area being studied is near the surface of the filament.
A Strain-Gage System for Fiber Testing
Authors: Dart S. Leonard , Peterson L.E.
Published: March 2008

A precision research instrument for the measurement of stress-strain-time properties of tex tile materials, which was constructed in the research laboratory of the American Viscose Corpo ration, is described. Classification of this instrument as a research tool rather than as a routine testing instrument allows more flexibility in operating conditions. It is of the constant-rate-of- extension type, for use on all textile materials from single filaments to fabrics. The instrument consists essentially of a constant speed drive, a Statham gage, and a Brown recording potentiometer.
Small-Angle X-Ray Scattering in Various Cellulose Fibers and Its Relation to the Micellar structure
Authors: Heyn A.N.J.
Published: March 2008

The study of the molecular structure of cellulose fibers by x-rays has been concerned until very recently with diffraction of only relatively wide angles. Almost no work has been done on the diffraction and scattering of x-rays within very small angles adjacent to the primary beam. The only fact known was that such "small-angle scattering" is produced by ramie and viscose rayon.

In the present study, the small-angle scattering by various cellulose fibers has been investi gated and it has been found that the scattering by different fibers is completely different.

The hypothesis that the small-angle scattering in cellulose fibers would be related to the micellar size and distance is substantiated by the fact that an experimental change of those distances results in a corresponding (inverse) change in the extent of the scattering. On this basis the difference in the scattering patterns of different fibers is explained as a difference in the size and distance of the cellulose micelles or crystallites.

An orientation of crystallites is also expressed in the small-angle diffraction pattern giving rise to the interesting phenomenon of "cross" formation when the crystallites form an angle with the long axis of the fiber. The angle between the intersecting lines of the cross proved to be related to the pitch of the spiral of the crystallites in the fiber.
The Viscosity of Newtonian, Pseudoplastic, and Dilatant Liquids
Authors: Krieble James G. , Whitwell John C.
Published: March 2008

An equation, for the calculation of the counterpart of viscosity for a pseudoplastic (or dilatant) liquid exists from the relationship existing between 1/ t and ΔP. Evaluation of ζ and Z defines the liquid property as completely as does η alone for a Newtonian liquid.

The counterpart of viscosity-ratio, which is independent of the rate of shear and viscometer dimensions, can be used to determine the intrinsic viscosity, [η].

The general character of the change in Z with the concentration is indicated.
A system for the Sizing of Women's Garments
Authors: Staples M.L. , DeLury D.B.
Published: March 2008

Body measurements for a representative number of American women (over 10,000) have been analyzed and a system is proposed for the sizing of women's garments based on this analysis. Size classes for the entire population of women 18 years of age and over have been developed in terms of independent control dimensions which are essential for the proper fit of the particular type of garment considered.

Dimensions have been computed for standard forms set up to represent each size class of the population. The calculations involve the use of the control variables and certain dependent variables required to define the size and shape of each mannequin.

A scheme for identifying the different size classes is also proposed. This scheme takes advantage of the fact that body measurements may be divided into three categories which are virtually independent of one another.
Dynamic Studies of Carpet Resilience
Authors: Barach J.L.
Published: March 2008

The problem of measuring the dynamic properties of a carpet is carried through several different steps which lead to the development of dynamic load measuring equipment designed to evaluate differences of carpet construction.
Specificity of Microbiological Attack on Cellulose Derivatives
Authors: Siu R.G.H. , Darby Richard T. , Burkholder Paul R. , Barghoorn E.S.
Published: March 2008

Data have been presented relating to the growth of 11 species of microorganisms isolated from deteriorated cotton fabrics on various derivatives of glucose, mannose, cellobiose, and cellulose. A high degree of specificity was exhibited. As long as there was at least one firmly bound substituent in every anhydroglucose unit, the resulting derivative was not susceptible to microbiological attack. Under such conditions the nature of the substituent has relatively little influence on the degree of resistance imparted. This was considered to be promising theoretical support for the underlying premise on which the idea of multipurpose topochemical reactions as a means of mildewproofing cotton fabrics was proposed.
Detergency Studies
Authors: Utermohlen William P. , Fischer Earl K. , Ryan Mary E. , Campbell Gordon H.
Published: March 2008

Natural soils on textiles usually contain both oily and solid components, and the generally accepted mechanism of soil removal postulates the emulsification and suspension of oil droplets or of solid particles covered with an intact oil film. Thus the ready removal of solid soil has been considered as dependent upon the presence of an emulsifiable oily soil, which had also served, prior to washing, to bind the solid soil more tightly to the fabric.

Washing tests have been made on samples of cotton cloth soiled to the same extent with lampblack or iron oxide in the presence of an oily liquid binder, of non-oily, water-soluble liquid binders, and of no binder at all. The ease of removal of the pigments was equal or only slightly different in all of these cases, indicating that the removal of solid soil and of oily soil . are separate phenomena and not interrelated to any great extent. This result indicates the desirability of reconsidering the theory of soil removal, and a possible improvement and simplification of laboratory test methods for detergent action.
A Study of Roving Coil Spacing on Bobbins
Authors: Bogdan J.F.
Published: March 2008

An equation, Cc = 8.365 H0.6617, makes possible the calculation of roving coils per inch for American carded cottons from a given roving number.

Relative roving density, width of coils, and rates of change are discussed. An application to a manufacturing problem is illustrated.
Some Replica Techniques Useful in Electron Microscopy of the Surface of the Wool Fiber
Authors: Makinson K. Rachel
Published: March 2008

Techniques have been developed for making replicas, suitable for examination in the electron microscope, of the surface of the wool fiber without subjecting the fiber to heat or pressure. Electron micrographs are reproduced to illustrate the appearance of normal wool fibers and of fibers subjected to various chemical and mechanical treatments. The results obtained support the view that the scales consist of a smooth layer overlying a more resistant furrowed structure. Certain other features of the scales, including a peculiar "fringed" edge, are also noted.
The Relaxation of Stress in Wool Fibers
Authors: Katz Sidney M. , Tobolsky Arthur V.
Published: March 2008

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.
Law of Critical Yarn Diameter and Twist Influence on Yarn Characteristics
Authors: Barella Alberto
Published: March 2008

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 the yarn is equal to the fiber density.

The influence of twist on contraction is examined and prediction formulas are given for cotton, woolen, worsted, and rayon yarns.
Testing Textiles on the Elmendorf Tear Tester
Authors: Painter E.V. , Chu C.C. , Morgan H.M.
Published: March 2008

Preliminary work has indicated that the tearing characteristics of textile fabrics depend on the speed with which the sample is torn. To obtain quantitative information on this speed depend ency, the tear-resistance of a variety of fabrics is being studied over a wide range of tearing speeds, from 0.05 in. per min. to impact at 10,000 in. per min. This range encompasses conventional laboratory test speeds and estimated end-use speeds of tear. The Elmendorf tear tester involves speeds which, while greater than those of conventional tear testers, do not approach the high speeds involved in service. This research was undertaken to determine the magnitude of and variations in the speeds of tear obtained with the use of the Elmendorf machine. The work repre sents only a portion of a broad research on the mechanism of tear, sponsored by the Chemicals and Plastics Section, Research and Development Branch, Office of The Quartermaster General, which has released this paper on the Elmendorf tester for publication.
The Molecular Structure of Wool Keratin
Authors: Goodings A.C.
Published: March 2008

Properties of the wool fiber are considered, and the information given by density and x-ray diffraction measurements in particular is used to deduce the structural pattern in keratin. Some of the implications of this structure are pointed out, and other folded molecular configura tions which are extensions of the proposed keratin structure are advanced and discussed in con nection with experimentally observed facts.
Gloss Measurements on Fabrics
Authors: Quynn Richard G. , Bernet Edwin J. , Fischer Earl K.
Published: March 2008

The gloss or luster of a surface is essentially a subjectively evaluated property which is re lated to the manner in which the surface reflects light falling on it. Although the impression or sensation of glossiness is a matter of common experience, measurement of this property in physical terms and correlation of the measurements with its psychological aspects are extremely difficult. The most satisfactory physical measurement involves the use of a goniophotometer, an instrument which measures the amount of light reflected from a surface at various angles. Curves showing intensity of reflected light vs. the scanning angle exhibit a peak at the so- called specular angle for surfaces rated as being of high gloss. Surfaces of more complex struc ture, such as those of fabrics, show a displacement of maximum reflectance from the specular angle; the displacement is related to the angle of the incident light. The curve shape is char acteristic for different fabrics.

This article describes the experimental measurement of reflectance by means of a goniopho tometer for a group of fabrics. The results are presented in the form of curves, computed "gloss indexes" or "gloss numbers," and visual ratings by different observers.
The Influence of Sodium Carboxymethyl Cellulose on the Suspending Power of Built Soap Solutions
Authors: Bayley C.H. , Weatherburn A.S.
Published: March 2008

The influence of sodium carboxymethyl cellulose (CMC) on the ability of soap solutions to prevent the deposition of carbon black on fabric during the detergent process has been stud ied. It was found that the presence of alkaline builders (sodium carbonate, modified soda, so dium metasilicate, and sodium orthosilicate) resulted in a decrease in the suspending power of soap solutions. The addition of CMC to such built soap solutions compensated to a considerable extent for this reduction in suspending power caused by the builder, although in no case did the suspending power equal that of the unbuilt soap. The maximum improvement in suspending power was obtained with a CMC concentration of 0.005%; i.e., 5% of the weight of soap used. In general, those builders which caused the greatest depression in the suspending power of the soap solution also showed the greatest improvement in suspending power on the addition of CMC.
The Application of Punched-Card Techniques to Data on the Physical Properties of Single Fibers
Authors: Wakeham Helmut , Wakelin James H.
Published: March 2008

The punched-card method is illustrated, with a description of the procedures used in analyzing the data on single cotton fibers. The samples were tested for 7 properties, from which 5 more were derived by computation. For each of these 12 properties there were prepared a histogram showing the distribution of the property values within variety groups, means and standard devi ations for 6 subgroups within each variety, and a three-factor analysis of variance of the means for all varieties and subgroups. The steps in obtaining these results from the punched cards are outlined. Some advantages of this method over the desk-calculator approach are discussed.
The Chemical Attack on Polymeric Materials as Modified by Diffusion
Authors: Katz Sidney M. , Kubu Edward T. , Wakelin James H.
Published: March 2008

The reaction of polymeric media with a chemical reagent generally involves the preliminary diffusion of the reagent through the polymer.

The effect of a relatively rapid diffusion of a chemical reagent into a cylindrical fiber on the over all rate of reaction is considered and the equation therefor is derived. The equation is applicable both to the extent of the reaction and to the decay of stress in the polymer, provided that a linear relationship between stress and extent of reaction is assumed.
The Kinetics of Wool Dyeing
Authors: Alexander P. , Charman D.A.
Published: March 2008

The kinetic curves for the adsorption on textile fibers of a dye having a long hydrocarbon chain (Carbolan Crimson BS) indicate that there is an initial rapid, but limited, reaction which is followed by a much slower reaction. The influence of electrolytes, dye concentration, and temperature was studied, and the magnitude of the initial adsorption was correlated with the surface activity of the solution. The dye thus taken up was shown to be located on the fiber surface which, being largely nonpolar, is an interface for adsorption of surface-active substances. It is suggested that the surface activity of the dye contributes substantially to its high anion affinity.
Use of Tabulator Data in the Analysis of Sliver and Roving Uniformity
Authors: Elting John P. , Barnes James C.
Published: March 2008

The addition of a data tabulator to any of the current instruments which graphically depicts sliver, roving, or yarn uniformity vastly extends the usefulness of the instrument. The present paper is intended to provide a working outline. It highlights the nature of the fundamental prob lems which arise as a consequence of the broad sampling and methods made practical by the tabu lator. Illustrations are based on the type of tabulator described by Rusca and applied to the Saco-Lowell sliver tester.

The subjects discussed are: the function of a tabulator, the type of data made available, the mini mum continuous sample length, periodicity of variations within a sample, variations between samples, and evaluation of mill machine performance.
The Detection of Modification in Animal Fibers I. Use of the Ratio (Hookean Slope in H2O/ Hookean Slope in Conditioned Air)
Authors: Burte Harris M.
Published: March 2008

The ratio (Hookean slope in H2O/ Hookean slope at 65% R.H.), where both measurements of the Hookean slope are on the same fiber, is shown to be independent of fiber cross-sectional area, and, for a given fiber type and previous history, the fiber-to-fiber variation of the ratio is small. Since chemical treatments markedly affect this ratio, its use to detect chemical process modification of animal fibers presents attractive possibilities.
Bikaner Wool, A Leading Carpet Wool, and Its Improvement
Authors: Mahal Gurbax Singh , Johnston Alexander , Burns Robert H.
Published: March 2008

Eight samples illustrating average and extreme types of Bikaner wool were selected from 28 samples received from the Government Livestock Farm at Hissar, India. These 8 samples were analyzed for fiber types, dividing them into true wool, hair, heterotype, and kemp fibers. Both the benzol test and microscopic cross-sectional images were used in the classification. Fiber thickness, stretched fiber length, and contour ratio were determined for the 8 samples along with the surface scale measurements for the different fiber types.
The Strength and Weakness of Cotton Fibers
Authors: Wakeham Helmut , Spicer Nancy
Published: March 2008

The structural reversals in cotton fibers are a preferred location of break when the fiber is ruptured in tension. With the aid of a polarizing microscope, observations were made of the fraction of fibers breaking at the reversals under various conditions of moisture content, specimen length, and chemical treatment. It is concluded that the cellulose in the region of the reversals is more highly crystalline than the cellulose between the reversals. The cause for breakage at the reversals is then explained on the basis of internal stresses at these points which cause the fiber to tear apart when tension is applied. The weak places between reversals which give rise to fiber rupture are believed to be at structural defects or thin places. The mean breaking stresses for fibers breaking at the reversals vary significantly from those for fibers breaking between reversals for some varieties of cotton. The distributions of weak-spot location and strength for reversals and structural defects are discussed for three varieties.
The Chemical Modification of Wool—Treatment with Formaldehyde Solutions
Authors: Brown Alfred E. , Hornstein Lydia R. , Harris Milton
Published: March 2008

A study was made of the reaction of formaldehyde with wool in order to determine optimal conditions for the production of wool that is more stable to alkali, as measured by the alkali- solubility test. Extremely mild treatments with dilute formaldehyde solutions confer an appre ciable degree of alkali-resistance to the wool, presumably by the formation of cross-links, and optimal alkali-resistance was obtained by treatment with 0.5% formaldehyde solutions at pH 6 to 8 for 6 hrs. at 50° C. Under these conditions, cystine linkages are not involved to any appre ciable extent, and the acid-combining capacity of the wool is changed only slightly. Although loss of sulfur from formaldehyde-treated wool occurs readily on treatment with hot alkaline solutions, the rate of loss of both sulfur and weight is less than in the case of untreated wool. The chemical evidence cited is in agreement with the view expressed elsewhere that additional cross-linkages are introduced in the wool molecule as a result of treatment with formaldehyde solutions. The lability of these new cross-linkages on exposure to acidic or hydrolytic condi tions is noted, and this behavior is compared with that of wool modified by other chemical reactions. Some comparisons are made with the use of the formaldehyde reaction in the regen erated protein-fiber field.
Extension and Relaxation of Nylon Filaments
Authors: Abbott N.J.
Published: March 2008

Measurements were made of the extension of nylon filaments under conditions of constant load for various lengths of time in air at 65% R.H. and in water. The extent of the recovery which took place after removal of the load was observed, and its dependence upon the magnitude and time of application of load, as well as upon the. immersion medium, was determined. Further recovery which could be effected by treatment with heat or swelling agents was investigated. Limitations in the use of the terms "elastic limit" and "nonrecoverable deformation" when applied to textile fibers are pointed out.
The Relationship Between the Structural Geometry of a Textile Fabric and Its Physical Properties
Authors: Backer Stanley , Tanenhaus Seaman J.
Published: March 2008

This paper examines the relationship of structural geometry to the abrasion-resistance of textile fabrics. It is pointed out that the durability of a fabric can be significantly altered by modifying its structural design, without change in the fiber used in its manufacture. Earlier textile studies and heretofore unpublished Army test reports provide illustrations of the relation ship between fabric geometry and durability. On the basis of this material, it is believed that lower rates of attrition can best be obtained by increasing the geometric area of contact between fabric and abradant. At the same time, fabric compliance and yarn mobility must be preserved at points of contact between the two rubbing surfaces. Thicker fabrics possessing minimum rates of attrition, consistent with other cloth requirements, will provide optimum durability for fatigue garments.
Frictional Properties of Jute and Some Other Long Vegetable Fibers
Authors: Bandyopadhyay S.B.
Published: March 2008

An inclined-plane apparatus has been devised for assessing the coefficient of friction of jute and allied fibers, their meshlike structures being duly considered. The nature of slip and the effects of combing, orientation of pads, normal pressure, moisture, and wax have been studied.
The Mechanism of the Wetting of Textiles
Authors: Gruntfest I.J.
Published: March 2008

Consideration is given to the implications of the data on the wetting of textiles that are obtained by the use of a hydrometer method. This method permits a much more detailed study of the wetting process than is possible by the more usual methods. Some effects of rate of immersion of skeins of gray cotton yarn, skein density, solution temperature, and mechanical action are described.

This work suggests a resolution of the wetting of textiles into two independent processes. One of these, the escape of occluded gas, is essentially mechanical. The other, the rate of advance of the liquid phase into the mass to be wet, is a physicochemical problem.

Some studies of the time-dependence of the surface tension of solutions of surface-active agents are also described and discussed. It appears that the rates of surface-tension lowering correlate quite well with wetting-agent performance.
Interpretation of Tests for Resistance to Abrasion of Textiles
Authors: Schiefer Herbert F. , Werntz Carl W.
Published: March 2008

The resistance to abrasion of sixteen cotton fabrics, which varied systematically in warp and filling yarn number and in ends and picks, was determined with the Schiefer abrasion testing machine, using No. 600A silicon carbide waterproof abrasive paper as the abradant and a total load of 2 lbs. on the specimen in one testing procedure, and a blade abradant and a total load of 20 lbs. on the specimen in a second testing procedure. The rate of abrasion in the first testing procedure was over ten times as great as that in the second. The results for the testing proce dures could be represented very well by the following equations: where R is the number of rotations of the abradant, W is the warp yarn number, F is the filling yarn number, E is the ends per inch, P is the picks per inch, and the other quantities are con stants. It was found that the rankings of the sixteen fabrics were different for the two testing procedures. This difference is due mainly to the fact that a given change in any one construc tion factor does not always result in quantitatively comparable changes in the resistance to abrasion obtained by the two procedures. This sort of difference is obtained, and should be expected, when comparing results of highly accelerated laboratory abrasion tests with results of comparatively slow rates of wear in service or performance tests. The resistance to abrasion of eight other fabrics of intermediate constructions obtained with each abradant agreed very well with the values computed by using the above two equations.
Cellulose Studies. Part XVI. The Reaction of Cellulose with Formaldehyde
Authors: Wagner Robert E. , Pacsu Eugene
Published: March 2008

A new method for reacting cellulose and formaldehyde in the vapor phase using acid catalysts is described. Acids as weak as boric acid were effective in introducing up to 6% covalently bonded formaldehyde. The results of reaction conditions where catalyst concentration ranged from 1%-10% and reaction temperature ranged from 110°-150°C are presented.

A chemical investigation of the structure of the product of the reaction showed that formalde- , hyde preferentially substitutes the secondary hydroxyl groups of cellulose to yield a 'structure represented by the general formula R-O-CH2-O-R', where R and R' indicate glucose residues in parallel chains.
Influence of Cross-Sectional Shape of Raw Cotton on Dimensional Changes in Mercerization Without Tension
Authors: Orr Rollin S. , Humphreys Geraldine C. , Grant James N.
Published: March 2008

The relation of the cross-sectional shape of the raw fiber to the changes that occur upon mer cerization without tension was studied for a number of cotton varieties representing a wide range of maturities.

Perimeters and diameters of fiber cross sections were measured by the use of an especially de signed instrument. Areas also were measured.

It was found that the percent increase in area and the percent decrease in perimeter caused by loose mercerization are dependent upon the cross-sectional shape of the original raw fibers. Flat fibers shrank more in perimeter and increased more in area than did round fibers. This was partly explained as being due to a change toward circularity.
A High-Speed Recording Yarn Tensiometer
Authors: Nistico F. , Sprague B.S. , Work R.W.
Published: March 2008

A yarn tensiometer is described which is capable of detecting and recording variations in tension occurring at a rate of the order of 100 cycles per sec. Tension variations of a con siderable magnitude at such frequencies have been shown to exist in yarn running on standard textile machinery.
Properties of Apparel Wools
Authors: von Bergen Werner , Wakelin James H.
Published: March 2008

Studies have been made on the physical and chemical properties and worsted processing char acteristics of two fine and two medium wools. Each of the wools studied was found to have essentially the same basic physical properties when reduced to the same cross-sectional area and to have the same chemical composition. The average diameter or fineness of a wool lot is the most important characteristic of the wool insofar as the efficiency of manufacturing operations is concerned. By aging the wool at 70°F and 70% R.H., an improvement in spinning and weav ing was observed. Steaming the wool in the form of roving was found to have the same bene ficial effect on spinning as aging under normal room temperature conditions. The aging process appears to be related to the relaxation of those stresses to which the fibers are subjected in previous processing operations.
Part II: Centrifuge Studies
Authors: Welo Lars A. , Ziifle Hilda M. , McDonald Allan W.
Published: March 2008

In an effort to develop a simple and rapid means of measuring swelling capacities in water of cotton and other fibers in mass, the centrifuge technique has been subjected to a rather extensive study. In this technique the swelling capacity appears as a function of the moisture retention after swelling and centrifuging.

Many previous workers have employed the centrifuge empirically for the removal of external, nonswelling water from fibers, but under conditions which have varied greatly as to time and intensity of centrifuging. In the present work, the complication of dealing with the two variables of time and speed of centrifuging simultaneously has been circumvented by noting that straight lines (to a high degree of approximation) were obtained when the moisture regains of the sample were plotted against the squares of the rotational speeds. The intercept of these straight lines on the moisture regain axis was characteristic for a given fiber in a given physical form. The intercept values were shown to be the same and reproducible for any selected centrifuging time of 20 min. or more, provided the minimum acceleration was above 3,200 g.

It was found that the zero-speed intercepts on the moisture regain axis, while highly re producible, did not represent true swelling capacities. That the intercept values were too large was shown by the sizable intercepts obtained with glass fibers, which obviously are incapable of swelling.

It was found that the excess moisture retentions could be reduced considerably in samples "oriented" so that the axis of the yarns or cords lay parallel to the direction of centrifugal force. Still further reductions occurred on cutting such "oriented" samples after centrifuging and determining the moisture regains of the cut lengths nearest the centrifuge axis.

Although it was not found possible to obtain true swelling capacities with the centrifuge, it appears that the technique could be very useful for detecting and measuring differences in water-holding capacity brought about by chemical treatment.

A quantitative theory of the behavior of the fiber-water system in the centrifuge was developed, based on simple capillary considerations.
Mechanics of Elastic Performance of Textile Materials
Authors: Platt M.M. , Klein W.G. , Hamburger W.J.
Published: March 2008

This report is concerned with the study of the mechanical properties of cordage yarns. The relationship between fiber properties and yarn performance is expressed mathematically by a method involving a generalized extension of the work of Hamburger [2] and Philipp [7]. The mathematical formulas representing the mechanical behavior of cordage yarns are shown to be useful by a comparison between theoretically calculated and experimentally obtained data. The validity and accuracy of the mathematical analysis is further tested by a detailed examina tion of the range of possible error due to unforeseen discrepancies between reality and the two assumptions: (a) a normal distribution of fiber properties, thus permitting the application of standard statistical treatment; and (b) no fiber slippage during the application to yarns of loads to rupture.

The results of the mathematical analysis are shown graphically over a range of fiber properties in excess of those evidenced by cordage fibers. Thus, if the assumptions made hold for all textile fibers, the behavior of other fibers than those normally used for cordage can be predicted for the case of yarns of cordage type.

Work is in progress covering further aspects of the research—namely, applying similar mathe matical analysis to the translation of yarn properties into strand, plied yarn, and rope structures.
Effects of Mechanical Processing of Cotton on the Physical Properties of Fibers
Authors: Grant James N. , Morlier Ora W. , Scott John M.
Published: March 2008

Fibers from ginned cotton and from 16/2s yarn of seven cottons of different physical properties were tested as a bundle and as individual fibers in order to determine what changes in properties, if any, could be attributed to the mechanical processing. Determinations of tenac ity, length array distribution, and crystal alignment revealed no consistent differences between the cottons before and after processing. The maturity of carded cottons was slightly lower. The weight fineness and breaking load of individual fibers were unchanged with processing, but elongation at break was decreased. A higher modulus in tension was obtained from load- elongation curves of processed fibers, with the greatest difference found for loads below 2 g.