bluuebunny/crossref_metadata_2025_split huggingface dataset:
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 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.
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 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.
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.
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.
The Stress Relaxation of Fibrous Materials
Authors: Kubu E.T. 
Published: March 2008

An apparatus has been built to study the relaxation behavior of wool, silk, and nylon as a function of reagent temperature, concentration, and hydrogen ion concentration. In distilled water all three materials show the same behavior over most of the time range studied—that is, a gradual relaxation of perhaps one-third of the initial stress, attributable in all likelihood to the destruction of hydrogen bonds. When the water is replaced by sodium bisulfite solution at pH 6.5, the rate of stress relaxation of wool keratin increases markedly. This change is at tributed to the scission of the disulfide cross-links in this material by the sulfite ion, in view of the finding that silk and nylon, which are free of cystine, are not affected by sodium bisulfite. Further experiments on wool have been made to show the effects of solutions of hydrochloric acid, urea, thioglycolic acid, and cysteine. The addition of 0.1 M HCl to an extended fiber re laxing in water produces a sharp drop in the stress; but the stress returns to its previous value when the acid is replaced with water. When 0.1 M hydrochloric acid is replaced by sodium bisulfite solution at pH 1.2, the rate of stress relaxation is much slower than that observed with sodium bisulfite at pH 6.5. The addition of 10 M urea to a fiber relaxing in water produces a relatively slow decay of stress. When the 10 M urea solution is replaced by a solution of 0.1 M sodium bisulfite in 10 M urea, the rate of stress relaxation is more rapid than that produced by sodium bisulfite alone. Cysteine and thioglycolic acid solutions at pH 6.5 produce an approxi mately exponential decay of stress when added to wool fibers previously relaxed in water.
The Tensile Behavior of Some Protein Fibers
Authors: Susich G. , Zagieboylo W. 
Published: March 2008

The tensile properties of wool, mohair, human hair, casein, Vicara, and silk, including their behavior when knotted, after repeated stresses (mechanical conditioning) and when swollen in water were investigated. The immediate elastic recovery, the delayed recovery, and the permanent set of these fibers were measured by means of a cycling technique using the Instron tensile tester and the Sookne-Harris fiber extensometer. Actual and relative values of elonga tion components under different testing conditions are demonstrated graphically from the be ginning of the stretching procedure up to rupture. Wool has an outstanding elastic recovery in the dry state, and its elastic behavior is improved after mechanical conditioning and when wet. Mohair and human hair, and to some extent casein and Vicara, have elastic properties similar to those of wool. The tensile behavior of silk is different, being characterized by considerable permanent set (dry and wet) and by high immediate elastic recovery after mechanical conditioning.
Change in the Fluorescence of Deltapine-15 Seed Cotton as a Result of Heat
Authors: Sheehan W.C. , Bailey T.L.W. , Compton Jack 
Published: March 2008

Examination of cotton samples in ultraviolet light revealed a variable color fluorescence of the entire bale stock, ranging from violet to blue-violet to ivory-white. Further experiments in dicated that the entire fiber mass could be made ivory-white by heating. Unlike commercially ginned fibers, hand-ginned fibers appeared uniformly bluish in ultraviolet radiations, but they could also be made ivory-white on heating. Experiments were carried out to ascertain whether these heated, white fluorescent fibers had different physical properties from the unheated, bluish fluorescent fibers. Of the various proper ties examined, only the bending stiffness was found to be different. The heated fluorescent fibers were the stiffer. The cause of this change in fiber fluorescence on heating was found to be associated with the formation of oxycellulose.
"S Factor," A Microbial Enzyme which Increases the Swelling of Cotton in Alkali
Authors: Marsh P.B. , Bollenbacher K. , Butler M.L. , Guthrie L.R. 
Published: March 2008

Exposure of cotton fiber to cell-free filtrates obtained from certain culture media after the growth of microorganisms increases the degree of subsequent swelling of the fiber in NaOH solutions. The active agency in the filtrates is here termed " S factor." Its action is measured by a previously described alkali-centrifuge test [12]. With the fungus Myrothecium verrucaria, S factor was produced during growth in media which included any of several cellulose-containing materials but not in any of several media lacking in cellulose. This finding and related results suggest that S factor consists at least in part of an enzyme or enzymes of the cellulase complex. A simple and reliable method of preparing Myrothecium filtrates of uniform and high S activity is reported. Several properties of S factor in Myrothecium filtrates have been observed. It is operative over a wide pH range. A very considerable uptake of the factor from solution by cotton fiber and a major increase in alkali-centrifuge value of the fiber occur in 10 min. Strength losses take place much more slowly. S factor is moderately stable in sterile filtrates at room tempera ture. Filtrates may be stored in frozen condition or may be dried at 40°C and stored dry with little loss in activity. The active factor is precipitated by acetone and is inactivated by crystal line pepsin. Although partial inactivation of S factor by heat occurred in 1/2 hr. at temperatures of 60°C and higher, complete inactivation did not take place even at much higher temperatures, and easily measurable activity remained even after heating at 100°C for 1/2 hr. Autoclaving at 15 lbs. steam pressure for 15 min. caused complete inactivation. The same filtrates also exhibited resistance to complete cellulase inactivation by heat when tested by a carboxymethylcellulose- viscosity test for cellulase.
Use of the Ballistic Pendulum for Impact Testing Of Tirecord
Authors: Lyons W. James , Prettyman Irven B. 
Published: March 2008

A ballistic pendulum tester for the absolute measurement of the energy (or work) of rupture of cords and yarns on impact is described, and the applied theory of the pendulum is briefly re viewed. Essentially, the test consists of placing a looped specimen, clamped at its ends, in a horizontal plane, so that it is struck in the bend of the loop by the pendulum at the bottom of its swing with sufficient energy to break the specimen. The difference in angular displacement of the pendulum with and without a specimen in place provides the measure of the energy lost in breaking the specimen. For expressing the results of the test as applied to tirecord, with reference to various condi tions, four physical quantities have been defined. The significance of these quantities is dis cussed, and the results of exploratory tests on a number of rayon constructions are given, showing the application of the various measures. By means of high-speed photography, used in connection with the pendulum apparatus, the impact rupture process in tirecord has been analyzed, and the energy separated into its force and elongation components. It is revealed that an experimental cord having higher-than-normal strength by the conventional test not only has a lower energy of rupture than a viscose con trol, but also appears to have lower impact strength. The analysis shows that the "breaking point," even in an impact test, is not an instantaneous phenomenon.
Improvement of Luster of Cotton
Authors: Fourt Lyman , Howorth Ruth M. , Rutherford Marjorie B. 
Published: March 2008

Luster is not an "absolute" property of the cotton or the yarn, but depends on the sheerness of the fabric, as well as on the weave pattern. One of the reasons for the greater apparent luster of sheer fabrics or thin layers of yarn is that there is less opportunity for light to be scattered within thin layers than in its return from the lower parts of thick layers of yarn. Such scattering adds an approximately equal amount to the reflectances at all angles and so lowers the apparent contrast ratio for the thicker layers. At the opposite extreme, the reflectance of individual yarns can be determined, and it is demonstrated that yarn removed from the fabric has nearly the same luster as the original yarn, if the weaving crimp is removed. Weaving crimp by itself reduces the measured luster, tending in the same direction as the effect of cross-yarns. The measurement of contrast ratio in yarns correlates with the average of numerous judg ments by observers. For fabrics, the ability of the eye to see sparkle or high lights, and to find the angle of maximum reflection, gives visual judgment some features not possessed by the more simple types of physical measurement, although even with fabrics there is a large degree of correlation.
Application of Electron Microscopy to the Study of Cellulose Acetate Fibers
Authors: Peck Virgil , Kaye Wilbur 
Published: March 2008

The application of electron microscopy to the study of cellulose acetate fibers has been demonstrated by the use of high-resolution Al-Be replicas. Abraded surfaces and the skin of fibers have been studied. Various materials used for guides abrade the fiber surfaces in different manners. Ceramic guides cause a sticking action, whereas metallic guides produce a shearing of the cellulose acetate surfaces. The skin consists of a highly oriented layer which is caused by drafting the fiber while solvent is still within the core. It is nonuniform and less extensible than the core. Other factors remaining constant, higher draft causes formation of a thicker skin, which is made up of layers. Yarns broken in tension show very jagged cracks and hairlike protuberances. Pigment dispersions and structural details are revealed by etching the fibers.
Optical and Electron Microscopic Studies of Cotton Fiber Structure
Authors: Rollins Mary L. , Tripp Verne W. 
Published: March 2008

The appearance, growth, and structure of a cotton fiber are described, and photomicrographs and electron micrographs are used to illustrate both gross and fine features of the cell wall morphology. Heretofore, microscopy of the fiber has been limited to the use of dispersion, swelling and staining methods, in plain and polarized light. The development during the present study of methods for isolation of individual components of the cell wall for purposes of electron microscopy has permitted interesting observations with the light microscope. Quantitative measurements of shrinkage in the isolated primary wall of the cotton fiber during mercerization confirm its restrictive influence on the fiber during swelling in various agents. Electron microscope studies have been made on isolated primary wall fragments which have been purified by removal of noncellulosic constituents by extraction. These have revealed that the cellulosic portion of the membrane is a network of fibrils interlaced in a sort of fabric in which the general system of orientation is axial on the outer surface and transverse on the inner surface. The cellulose framework is impregnated with a complex of waxes, pectinaceous, and proteinaceous substances. The first layer of secondary thickening, called the "winding layer," has been isolated from 17-day old cotton fibers and photographed with both optical and electron microscopes. It is revealed to be a continuous sheet or layer made up of alternating bands of fibril bundles which spiral about the fiber at an angle. The wider bands have a closely packed parallel arrangement of fibrils while the narrower bands which connect them consist of two systems of fibrils at right angles to one another in an open-weave pattern. Electron micrographs of fragments of the main body of the secondary wall show an entirely different pattern of fibril arrangement from either the primary wall or the winding layer.
The Improvement of Luster of Cotton
Authors: Fourt Lyman , Howorth Ruth M. , Rutherford Marjorie B. , Streicher Pauline 
Published: March 2008

The relations of luster and fiber properties have been studied in numerous specimens of a limited number of varieties, both as natural and as mercerized yarns. The differences of group averages for natural yarns of several Upland varieties appear due to yarn structure factors, but the high luster of American-Egyption cotton must be due to other factors. The gain in luster on mercerization tends to be greater, the greater the original luster, both between and within variety groups. Within one variety, Deltapine 15, the trend of the luster of mercerized yarn is to increase with increase of the fiber properties of length, wt./in., and maturity, or combinations of these. Fiber strength has no consistent relation to luster within this group. Length shows the same between and within group relations, but wt./in. shows the opposite relations between groups, and maturity shows no trend between groups. Fiber properties or combinations can be used to select for better than average luster in the longer cottons, but there is still considerable range and overlapping. The improvement possi ble by selection within a group is small compared with either mercerization or use of American- Egyption instead of Upland cotton, but suggests the worth of continued studies in this direction.
The Relationship of the Geometry of Plain Knit Cotton Fabric to Its Dimensional Change and Elastic Properties
Authors: Fletcher Hazel M. , Roberts S. Helen 
Published: March 2008

A study was made of the geometry of 34 different plain knit cotton fabrics which were knit, in a wide range of stiffness, of six different yarns (12/1, 20/1, 28/1, 36/1, 40/1, 50/1). Stitch length in terms of course and wale spacings and diameter of yarn ranged from l = 2 p + w + 4.34 d to l = 2 p + w + 6.37 d, as compared with the theoretical value of l = 2 p + w + 5.94 d which Peirce derived. Both the gray and the finished fabrics exhibited distortion. Laundering with screen- or tumbler-drying brought about rearrangement in the structure so that the data for wale and course spacings of the laundered fabrics followed the parabolic curve p2 = a ( w + b) . When fabrics were given a relaxation treatment to remove distortion, the data of wale and course spacings both before and after laundering also followed a parabolic curve. For the relaxed fabrics, dimensional changes in length and width in laundering were not excessive and did not vary with cover factor (stitch length/diameter of yarn). The elastic properties changed greatly with cover factor for the unlaundered, relaxed, and laundered fabrics. As cover factor increased, the strain increased linearly when the fabrics were not distorted. Cover factor varied linearly with recovery and permanent set, with delayed re covery and permanent set increasing and immediate elastic recovery decreasing. Poisson's ratio increased somewhat with cover factor when the fabrics were not distorted.