bluuebunny/crossref_metadata_2025 huggingface dataset:
Measurement of Fiber Orientation
Authors: Lindsley Charles H.
Published: March 2008

A method is described for estimating the extent of fiber orientation in lap, sliver, etc., thus making possible a quantitative evaluation of the effectiveness of carding and drawing operations in aligning the fibers. In principle, the method involves clamping the sample in a special device, cutting out a section of fixed length ( e.g., 1/2 in.), and straightening out the fibers by combing. Then, all fibers found to be longer than 1/2 in. must have been out of alignment in some way in the original section. From the ratio of the portion in excess of 1/2 in. to 1/2-in. portion an orientation index is calculated. This index serves to arrange the samples in the following expected order of increasing orientation: card sliver, drawing sliver, finisher drawing sliver, and roving. Combed roving shows almost complete parallelism. Applications of the method are suggested.
Glycosidic Methoxyl Groups in Methanolyzed Cellulose
Authors: Reeves Richard E. , Mazzeno Laurence W. , Hoffpauir Carroll L.
Published: March 2008

Oxidation by a glycol-cleavage reagent has proved that the acid-labile methoxyl groups in methanolyzed cellulose are linked in glycosidic combination (1 per molecule), and not in an acetal structure, which would require 2 such groups per molecule. Evidence confirming the glycosidic structure was obtained by fractionating methanolyzed cellulose to the point where number- average molecular weights must be calculated on the basis of 1 methoxyl group per molecule.

The rate of removal of methoxyl groups from methanolyzed cellulose upon acid hydrolysis was reinvestigated. The rate is roughly comparable to the rate of hydrolysis of methyl gluco pyranosides. These findings contradict the basis for a claim, based on copper-number deter minations, that the methoxyl groups of methanolyzed cellulose are very rapidly hydrolyzed and are of the acetal type.
The Technical Possibilities for a Regenerated Silk
Authors: Wakeham Helmut , Toner R.K. , Jolley H.R. , Taylor H.S.
Published: March 2008

The molecular properties of silk fibroin are such as to make the regeneration of silk worthy of serious consideration. Not only is the molecular weight such as to indicate at least 500 units in the polymer, but, also, the component residues are among the simplest amino acids, without bulky side groups. Thus, the interchain attraction is the highest of several representative polymers. The mechanical problems of silk regeneration are not easily overcome, however. Many solvents degrade the fibroin appreciably, and, so far as is known, aqueous solutions of concentration com parable to that found in the silkworm have not been made. The structural simplicity which gives rise to good polymer properties is also conducive to instability of aqueous solutions. While important in an over-all appraisal of silk regeneration, the economic problems are not discussed in this paper.
The Structure and Mechanical Behavior of Cellulose Fibers
Authors: Herrent P. , Lude A.
Published: March 2008

The present reticular concept of the internal structure of cellulose gels is inadequate from several points of view. Principally, it fails to take sufficient account of purely energetic effects in the mechanical behavior of the gels, and is based primarily upon entropy changes. Further more, the marked influence of degree of polymerization and of concentration of cellulose solutions upon the course of coagulation has been largely neglected.

The structure here proposed is a double network of macromolecules—a primary network, formed by the assembly of meshes the knots of which are small crystallites, and the sides of which are bundles of macromolecules, bound more or less closely to one another through their convolu tions, comprising the secondary network. This structure makes it possible to introduce into the system the changes in internal energy hitherto lacking. We thus obtain a better interpretation of the experimental facts and are able to fill in certain gaps in the former theory, taking into account present ideas regarding the state of aggregation of macromolecules in solutions and the density of the amorphous regions in cellulose.
Modification of Wool by the Application of Linear Synthetic Polyamides
Authors: Jackson D.L.C. , Lipson M.
Published: March 2008

The effect of surface deposits of nylon and N-substituted nylons on the abrasion-resistance and felting shrinkage of wool has been determined. N-methoxymethyl nylons are much more effective than nylon itself, when applied from solution, in increasing the abrasion-resistance of wool fabric, but not in decreasing the felting shrinkage of the fabric. If the N-methoxymethyl nylon is first applied to the wool fabric from alcoholic solution and then hydrolyzed in situ by approximately 2N HCl, the polymer is found to confer non-felting properties on the wool. A deposit of approximately 3% by weight of polymer has been found to eliminate entirely the felting shrinkage of wool fabric under the conditions of test. The optimum degree of substitution of the nylon for the production of non-feltability is between 5% and 6% combined formaldehyde, which corresponds to between 20% and 24% —NH groups substituted.

The effectiveness of these polymers in increasing abrasion-resistance and decreasing felting shrinkage is explained on the basis of their adhesion to and covering power on the wool fiber.
Mechanics of Elastic Performance of Textile Materials
Authors: Kaswell Ernest R. , Platt Milton M.
Published: March 2008

As a first step in studying the factors which determine the efficiency of cordage structures, a series of related experiments have been performed on the common cordage fibers. The basic mechanical properties of Manila and domestic Abaca, Sisal, Henequen, and Sansevieria fibers have been determined by a study of their one-time loading to rupture and repeated-tension char acteristics. Data are presented on: (1) those fiber properties deemed most significant in terms of cordage use; (2) the effects of processing fibers into yarns; and (3) mechanical properties under varying ambient atmospheric conditions representing some of the extreme environments under which cordage is used.
The Measurement of Dynamic Modulus and Energy Losses in Single Textile Filaments Subjected to Forced Longitudinal Vibrations
Authors: Dunell Basil A. , Dillon J.H.
Published: March 2008

Apparatus and techniques for measuring the dynamic properties of single fibers in the frequency range 1-100 cycles/sec. at 70° F and 65% R.H. are described. For the viscose rayon, acetate rayon, nylon, feather keratin, silk, and polyethylene fibers studied, it was found that the quantities ηω and E were approximately independent of frequency in this range, where η is the internal friction, ω the radian frequency, and E the dynamic modulus. Measured values of the energy dissipated per cycle were found to be proportional to the square of the amplitude, in accordance with the prediction of the simple differential equation of vibration assumed (viscous damping and Hookean elastic reaction). Stress relaxation data were obtained with the same fibers and the results are given. Theoretical interpretation of the results is given in another paper [19].
Contradictory Data on Spiral Structures in the Secondary Cell Wall of Fibers of Flax, Hemp, and Ramie
Authors: Roelofsen P.A.
Published: March 2008

Althought the microscopy of the well-known textile fibers flax, hemp, and ramie is familiar to many people and the spiral structure of their cell-wall layers is mentioned in many textbooks, the study of the original literature on this point disclosed many contradictory data. However, there cannot exist essential differences between the samples studied by the different authors, since there are no conflicting data on the direction of twist shown by the fibers on wetting or drying, nor on the optical behavior when studied with a polarization microscope.

A reinvestigation revealed that in flax there are not two, but three, layers with different spiral structure. Since usually either the outer or the inner one is very difficult to discern, previous authors described two of them, either the two outer or the two inner ones. In ramie and in hemp fibers the spiral structure of two outer layers is identical with those of flax, although the slope of the spirals and the thickness of the layers, of course, differ. If here, too, a third, innermost layer with different spiral structure could be found, the conflicting data in the literature would be understandable.
The Sorption of Synthetic Surface-Active Compounds by Carbon Black
Authors: Rose G.R.F. , Weatherburn A.S. , Bayley C.H.
Published: March 2008

The sorption on carbon black of a number of types of anionic, cationic, and nonionic surface- active compounds from aqueous solutions has been measured. It is shown that the sorption of these compounds does not conform to the Freundlich adsorption isotherm over the whole of the concentration range studied (0.01%—0.2% by weight). In the majority of cases an abrupt change in slope of the curve occurred at concentrations which appear to correspond, at least approximately, to the critical micelle concentrations of the various compounds. At con centrations above this critical point the plot of log X vs. log C appeared to be linear, but below the critical point considerable deviation from lineality was observed in some cases. The sorption of sodium alkyl sulfates increased with increasing chain length of the alkyl group at constant temperature, and decreased with increasing temperature at constant chain length. A series of compounds differing widely in chemical constitution, and including both anionic and cationic agents, were shown to be remarkably similar with respect to the general level of adsorption. Two typical nonionic compounds were found to be sorbed somewhat more strongly, particularly at higher concentrations, than any of the other compounds investigated. The addition of sodium sulfate to solutions of anionic compounds resulted in an increase in the sorption of the latter in every case.
The Measurement of Stiffness in Textile Fabrics
Authors: Abbott N.J.
Published: March 2008

In Part I the subjective evaluation of stiffness is used as a standard with which to compare the results obtained from five laboratory methods of measuring stiffness. Measurements were made on a range of nineteen fabrics of varying fiber content, weave, and weight. The results indicated significant correlation in four of the five methods. The test was repeated with a new range of of eleven fabrics, with approximately the same results. The Peirce cantilever test was selected as being the most convenient to carry out in the laboratory, and at the same time giving good cor relation with the subjective estimate. Part II describes a more detailed examination of certain aspects of the cantilever test, and a specific technique is recommended which combines simplicity of equipment with ease of measurement.
Tensile Recovery Behavior of Textile Fibers
Authors: Susich George , Backer Stanley
Published: March 2008

The recovery data available on textile materials are scarce and difficult to compare. Very few data on fibers have been presented in which differentiation is made between immediate and delayed recovery. Until the present, no adequate method except the pulse-propagation technique has been known to separate these strain components. Using the Instron tensile tester, a cycling method was developed to measure directly the total elongation and permanent set and to permit also determination of the immediate and delayed recovery. The conditions of the tests were standardized. Some studies were made on the effect of deviations from the standardized conditions.

The recovery behavior of 25 samples representing 16 different textile fibers was measured under the standardized conditions. Their recovery behavior is presented by tabular data and by two series of rectangular graphs. The values of immediate and delayed recovery and of permanent set as obtained describe the recovery behavior of fibers with adequate accuracy from the initial application of stress to the breaking point. The recovery behavior was found to be characteristic for any material; however, it was affected by the history of the samples. The recovery of Fiberglas, cotton, Saran, viscose, acetate, nylon, Orlon acrylic fiber, Fiber V, Vinyon CF-HST, N, NOZZ, NORU, wool, casein, and polyethylene is discussed, and an at tempt is made to interpret the data.

Results obtained in this study have been correlated to known recovery data of other authors: Meredith, Maillard and coworkers, and Hamburger.
The Influence of Weathering and of Microorganisms on the Aqueous-Extract pH of Cotton Fiber
Authors: Marsh P.B. , Guthrie L.R. , Butler M.L.
Published: March 2008

Exposure of cotton in the field to wet weather following normal opening of the boll and fluffing of the fiber resulted in increases in the pH of aqueous extracts of the fiber, as determined by methods herein described, from a level in the general range of pH 6.3 to 7.3 for the un- weathered fiber to progressively higher values. The maximum pH attained was in the range of 9.5 to 10.0, and was sometimes reached within a period of 5 days.

Cotton fiber subjected to wet weather during the process of boll opening, with the consequent unfluffed and darkened appearance characteristic of "fungus tight-lock" and "boll rot," had pH values ranging from 5.3 to 9.7. In the case of the common Diplodia tight-lock, serious fiber weakening and fiber disintegration were accompanied by pH values from 5.6 to 6.8.

Pure-culture laboratory tests involving inoculation with fungi and humid-atmosphere incuba tion of fiber and unbleached cotton fabric, followed by pH determinations, indicated that several microorganisms, including certain types of common occurrence on field-weathered cotton, may bring about very rapid pH increases of the same general magnitude as those observed with fiber exposed to humid weather in the field. Both cellulose-decomposing and noncellulose-decom posing fungi brought about pH changes, which were upward in direction for 24 of the 27 isolates tested. Once high pH values were attained, no subsequent decrease in pH occurred dur ing incubation periods of 4 weeks' duration. On water-saturated cotton fiber mats, certain com mon bacteria and a common yeast produced pH increases. Data suggest that increases in the aqueous-extract pH of cotton fiber may be caused by the decomposition of malic or other organic acids in the fiber by microorganisms.

Fiber which had attained a high aqueous-extract pH during weathering exhibited a decline in this value with time in storage. In tests here reported, the higher the original pH of the sample, the more rapid was the initial rate of decline in pH during storage. A decline in pH may occur also while the fiber is still on the plant in the field.

The pH test appears to offer promise as a rapid method of fairly wide applicability for de tecting the growth of microorganisms on cotton fiber. The pH change measured is a response to growth on the noncellulosic constituents of the fiber and must be supplemented by further tests if one is to determine whether or not structural damage to the fiber has occurred.
Apparatus for Evaluating Warmth of Textile Fabrics
Authors: Tallant John D. , Worner Ruby K.
Published: March 2008

A semi-automatic apparatus requiring minimum operator attention has been assembled for measuring the thermal transmission of fabrics while subject to moving air at constant tem perature. The apparatus employs the principle of measuring the difference in the amount of energy required to maintain constant temperature in a body when bare and when covered with the test specimen. Conditions have been set up with an air velocity of 12 to 13 m.p.h. so that per formance under fairly severe conditions of use can be approximated. Results are expressed as "thermal efficiency." Formulas are given for converting to other units as desired. The ap paratus has been tested with a variety of fabrics ranging from thin, plain-weave, nylon cloth to heavy woolen blankets, and has been found to differentiate among them in a manner that ap parently takes into account the various fabric properties.
Structural Orientation in Cellulose Acetate Filaments and Its Relation to the Dichroism of Adsorbed Dyes
Authors: Morey D.R. , Martin E.V.
Published: March 2008

Factors influencing structural orientation and oriented adsorption of dyes in cellulose acetate filaments were studied using methods based on x-ray reflections and on dichroism. The deriva tion of a method of computing the percentage orientation from the density of the 002 ring is given. A method for determining the percentage orientation using dichroic dyes is described. In evalu ating the data obtained by the latter method, the x-ray data were used as standard.

The dyes examined are classified according to their ability to adsorb directionally on the cellu lose acetate substrate. Dyeing conditions affecting results obtained by means of dichroism are discussed in relation to filament structure.

Orientation measurements by both methods were made on continuous-filament yarns drafted to various extensions. The values obtained by the x-ray method were generally higher than those obtained by the method based on dichroism.
The Relationship Between the Structural Geometry of a Textile Fabric and Its Physical Properties
Authors: Backer Stanley
Published: March 2008

This paper is a study of the geometry of fabric interstices as related to air flow through cloth structures. It assumes that textile yarns act as flexible, inextensible, circular cylinders. Modes of thread interlacing are classified, and minimum horizontal pore areas for each type of intermesh are calculated. Minimum pore areas are then related to the air permeabilities of both open- and close-weave fabrics. Considerable attention is devoted to the elements of fabric structure which complicate geometric calculations of pore-sectional areas. These include crimp balance and yarn flattening and ballooning. Further attention is given to the relative importance of interfiber spacings and to the interaction between yarn and fabric structures. Finally, this study emphasizes the significance of the primary and secondary structural features of woven fabrics in the design of materials which must satisfy air-permeability requirements.
Effects of Cotton Fiber Fineness on the Physical Properties of Single Yarns
Authors: Fiori Louis A. , Brown John J.
Published: March 2008

The effects of the single fiber property fiber fineness on the physical properties of single yarns, both coarse and fine and of varying twist, were investigated. To permit the study of fiber fine ness while maintaining other important properties approximately constant, a special technique was used which controlled the length factor by reducing all the cottons to common quartile and mean lengths. The cottons selected—Seaberry Sea Island, Mesa Acala, Tanguis, and Rowden 41—B—represented extremes in fineness, ranging from 2.9 to 5.6 μg. per in., and had other impor tant fiber properties approximately equal. The study showed mainly that a relationship exists between fiber fineness and the turns per inch required in a single yarn to obtain optimum yarn- strength benefits. Low-twist yarns decreased less rapidly in strength from maximum strength when made from fine than when made from coarse fibers. In contrast, high-twist yarns de creased more rapidly in strength when made from fine rather than when made from coarse fibers. Yarns made from coarse fibers required more twist to attain maximum yarn strength than those made from fine fibers. The study also revealed that fiber fineness does not materially affect yarn elongation. In addition, it was found that fiber fineness is a critical factor of roving twist.
Some Observations on the Evaporation of Water from Cellulose
Authors: Bogaty Herman , Campbell Kenneth S. , Appel William D.
Published: March 2008

The influence of water on the deterioration of cellulose is discussed, with special reference to deterioration at the brown line which forms when water rises in cotton by capillary action. The brown, fluorescent, water-soluble material results from the evaporation of water at the cellulose-water-air interface. Oxycellulose of the mildly reducing acidic type is formed. The oxidation appears to occur in part at the primary hydroxyl group, with the formation of polyglu curonic acid followed by chain scission and formation of soluble, low-molecular-weight frac tions. The deterioration proceeds even at moderate temperatures and in diffused light indoors. The brown-line effect undoubtedly contributes significantly to the degradation of cotton during its production, processing, and use.
The Oxidation of Cellulose by Ozone in Small Concentrations
Authors: Bogaty Herman , Campbell Kenneth S. , Appel William D.
Published: March 2008

Laboratory experiments show that ozone in amounts which may occur in air at the earth's surface (up to 0.06 part per million) deteriorates cotton textiles when they are wet. The deterioration is slight in comparison with that from other elements of "weathering," such as light, heat, wetting and drying, and microorganisms. Fifty days of exposure to air containing 0.02 to 0.06 part of ozone per million was required to reduce the breaking strength of wet print cloth 20% and increase the fluidity in cuprammonium solution from 8 to 16 rhes. When exposed dry, the cloth underwent little or no change in these characteristics. An increase in concentra tion of ozone led to an increase in the deterioration of the cellulose.
Swelling Capacities of Fibers in Water
Authors: Welo Lars A. , Ziifle Hilda M. , Loeb Leopold
Published: March 2008

Swelling in water is one of the important fundamental properties of cellulosic fibers, and is also a factor in determining the proper fiber for a specific utilization. An example of this is the selection of cottons for self-sealing fabrics. Since existing techniques for measuring swelling capacities, as they have been used, are tedious and time-consuming, it was desired to find a rapid method which would be sensitive enough to establish, with certainty, small dif ferences in swelling capacity due to variety, conditions of growth, and state of maturity such as might be decisive in the choice of a cotton for an application dependent upon swelling. In Part I of this study a method is discussed for determining swelling capacities of cotton and other fibers. It is based on the measurement of the rate of loss of moisture from a moisture- saturated sample. Experimentally, this method is exceedingly simple—the fiber samples, fully swollen and containing excess water, are dried very slowly and weighed periodically. It is shown that for a time the moisture is lost at a nearly constant rate. Eventually, however, the drying rate changes and thereafter steadily diminishes. It is believed that this change occurs only after all nonswelling water external to the fiber has evaporated. The moisture regain at this point of transition in the desiccation rate is considered to be indicative of the maximum water-holding capacity of the cellulose— i.e., the swelling capacity. The moisture regain values determined are in general agreement with the regain values estimated from adsorption isotherms at 100% relative humidity. The maximum regain values from the desiccation rate technique, when expressed in terms of volume increases, agree with the swelling capacities as determined by microscopic measurements.

Although the experimental method is simple and direct and more rapid than microscopic methods, the long drying periods required make it suitable mainly for use in research when time is not an important consideration.
Aerodynamic Properties of Screens and Fabrics
Authors: Hoerner S.F.
Published: March 2008

General rules for the pressure loss of flow across wire screens and simple fabrics are devired herein from the available test data. At higher Reynolds numbers the results obtained agree satisfactorily with the Borda-Carnot theory, which considers the dynamic losses to be due to a sudden expansion of the cross section behind the openings of an obstacle. On the other hand, at very low Reynolds numbers the pressure loss seems to be proportional to the velocity, corresponding to the Hagen- Poiseuille kind of flow. In the intermediate range of the Reynolds number the loss coefficient is found by statistical analysis to be a function of this number and the solidity ratio of the material.
The Swelling of Human Hair in Water and Water Vapor
Authors: Stam Paul B. , Kratz Robert F. , White Howard J.
Published: March 2008

Data are presented on the swelling of free and strained hair fibers in water and water vapor. The strained hair fibers were either under constant load or at constant elongation. In some cases rates of swelling are also shown. The swelling isotherms of the free fibers follow the volume changes predicted from density measurements (for wool) except at very high relative humidities. Straining the fiber may either increase or decrease the amount of swelling, depend ing on the type of experiment. An attempt to develop a statistical mechanical model to explain the equilibrium absorption and swelling behavior of a hair fiber is only partly successful. Finally, there seems to be evidence from the rates of swelling to indicate inhomogeneities in the hair with respect to its response to mechanical deformations.
The Geometry of Knit Fabrics Made of Staple Rayon and Nylon and Its Relationship to Shrinkage in Laundering
Authors: Fletcher Hazel M. , Roberts S. Helen
Published: March 2008

The geometry of six plain, six rib, and three interlock circular knit fabrics made of staple fibers of viscose, acetate-viscose, and nylon has been studied. Data on both gray and finished fabrics for stitch length, diameter of yarn, and wale and course spacings were used in evaluating the equations derived by Peirce for length of yarn in one stitch and for weight per unit area. Measured stitch length ranged from l = 2 p + w + 4.18d to l = 2 p + w + 6.74d, as compared to the theoretical value of l = 2 p + w + 5.94d which Peirce derived. Weight of the fabrics calculated by Peirce's equation showed good agreement with that obtained by weighing a known area.

In laundering tests, it was found that the various yarns shrank or stretched less than 3% in the finished fabrics. The data of wale and course spacings of both the laundered gray and laundered finished fabrics followed parabolic curves. Curves relating the wale and course spacings of the unlaundered materials conformed to no orderly pattern. Those unlaundered materials in which wale and course spacings approximated the parabolic relationship of the laundered fabrics changed the least in the length and width dimensions. Shrinkage in area increased with knitting stiffness for all of the gray fabrics and for the finished viscose; but, for the finished acetate-viscose and nylon, shrinkage in area usually decreased as the knitting stiffness increased.
Some of the Factors Influencing Yarn Tension in Warping
Authors: Dyer R.F. , Faw W.G. , Beard R.L.
Published: March 2008

The successful warping of coned yarn depends to a major degree on applying equal and con stant tension on each end of yarn so that smooth homogeneous beams are produced. This paper reports a study made to determine the factors which influence warping tensions. Several vari ables inherent in the yarn or in a coned yarn package which affect withdrawal tensions have been found. The variables of yarn twist, ballooning of the yarn during withdrawal, yarn speed, and cone size are discussed as factors which control withdrawal tension in warping. The magni tude and frequency of tension variations caused by these factors are shown by graphic records obtained by suitable recording instruments. The three basic methods for applying tension to the yarn have been classified as multiplying, additive, and compensating. The limitations and advan tages of tension devices incorporating these basic methods in pure and combined forms are dis cussed with reference to the basic equations and graphic records.
Chromatographic Studies of the Silk Fiber
Authors: Bryant F.
Published: March 2008

Sericin isolated from raw silk was found to be readily separable into water-soluble and water- insoluble fractions. Such fractions were qualitatively analyzed for amino acid content by paper partition chromatography, and distinct differences between the fractions were detected.
An Automatic Yarn Load-Elongation Recorder
Authors: Breazeale F.B. , Irvin H.D.
Published: March 2008

An apparatus for recording the load-elongation properties of yarns is described. Essentially, it subjects a length of yarn or staple to a constant rate of elongation to break, or to a repeated cycling of extension and retraction between either predetermined loads or elongations. Auto matic recording of these latter traces at logarithmic intervals may be employed, and an automatic 1-min. delay between cycles at zero extension or zero load may be used if desired. Several traces obtained with this equipment are shown to illustrate its performance.
The Evaluation of Textile Sizes
Authors: King David E. , Weil Henry A. , Condo Fred E. , Rutherford Henry A.
Published: March 2008

The effect of sizing mixtures on the slubby portions of a staple yarn was determined indirectly by the application of the size to a cotton roving and subsequent testing of the roving for strength, ultimate elongation, and stiffness. In contrast to the methods which employ yarn as the base material for the application of the size, large differences between sizing mixtures were found by this procedure.

The evaluation method which was investigated proved useful for the screening of sizes for knitting yarns in which the failure to give good knitting quality was caused by the presence of slubs.
Silicon-Containing Azo Dyes
Authors: Sunthankar S.V. , Gilman Henry
Published: March 2008

In an examination of the dyeing properties and lightfastness of some azo dyes, prepared by coupling several diazonium salts with m-trimethylsilyl- and m-triphenylsilyl-dimethylaniline, it has been observed that most of the dyes have a fairly good substantivity for cellulose acetate, nylon, silk, and wool, but their lightfastness varies from moderate to good.

In a comparative study of the shades obtained from 2-naphthol and its 6-trimethylsilyl and 6-triphenylsilyl derivatives, by the ingrain process, it has been found that the R3Si substituent has an unfavorable effect on both the substantivity and the lightfastness.

Absorption spectra of some silicon-containing azo dyes have been recorded, and the spectra have been compared with those of the corresponding hydrogen and methyl analogues. The gen eral bathochromic shift observed in the spectra of the silicon-containing azo dyes has been attributed to the crowding effect of the bulky R3Si group.

An examination of the pH range of some silicon-containing azo dyes has revealed that the R3Si substituent does not have any favorable effect on the pH range of the dyes.
Use of a Servo System for Automatic Operation of the Fibrograph
Authors: Tallant John D.
Published: March 2008

A simple method, which requires virtually no change in the Fibrograph, is described for converting the instrument to automatic operation by the use of a servo system. The accessories required are rugged and are commercially available. Smoother fibrogram curves are obtained by this method, and less time is required because the operator is free to comb the next test sample while a fibrogram curve is being drawn.
The Vibroscopic Method for Determination of Fiber Cross-Sectional Area
Authors: Montgomery D.J. , Milloway W.T.
Published: March 2008

The elementary theory of the vibroscope, a device for determining mass per unit length of a fiber, is reviewed and the corrections from the simple law due to elasticity are discussed. Various forms of apparatus are described. Comparisons of vibroscope results with results of other methods are given. Agreement is found within the limits of precision of the methods.
Studies on the Partial Carboxymethylation of Cotton
Authors: Daul George C. , Reinhardt Robert M. , Reid J. David
Published: March 2008

Additional studies have been made on partial carboxymethylation—the reaction between mono chloroacetic acid and cotton in the presence of sodium hydroxide—and on the products ob tained. A thorough investigation of the time and temperature of reaction and concentration of reagents showed that relatively small amounts of monochloroacetic acid, properly applied, alter the properties of cotton considerably.

Pilot-scale carboxymethylation of cloth was conducted which showed that it is possible to use standard textile machinery in the process. The cloth resulting from this treatment had a crisp liand with a slightly starched feel.

More detailed investigations than reported previously were made, and it was found that the tensile strength and elongation of treated cotton are increased, dyeing properties are changed, and soiling-resistance and soil removal are increased. It was also learned that the treated materials are unaffected after one year's storage.
Crease-Resistant Cloth from Partially Carboxymethylated Cotton
Authors: Daul George C. , Reinhardt Robert M. , Reid J. David
Published: March 2008

A method of applying resin treatments to the acid form of partially carboxymethylated cot ton cloth to produce crease-resistance has been developed. The acidity of the carboxyl group and the higher swellability are advantageous for overcoming two difficulties met in the usual methods of producing crease-resistant cotton cloth by resin treatment. The presence of the acid carboxyl group supplies a built-in catalyst, making the addition of catalyst unnecessary, in this way avoiding the prepolymerization of resin baths which contain added catalysts. The high swellability of the modified cotton allows easier penetration of the resin-formers and larger pickup of resin, with the production of cloth of equivalent crease-resistance, of superior hand and abra sion-resistance, and better in most other physical properties, in comparison with the unmodified resin-treated cloth.

The process of carboxymethylation, which consists of impregnating cotton cloth with a weak solution of monochloroacetic acid followed by treatment with strong sodium hydroxide, is com mercially feasible and can be carried out on ordinary textile equipment.
An Improved Vibroscope
Authors: Dart S.Leonard , Peterson L.E.
Published: March 2008

An improved model of the constant-frequency type vibroscope t used for measuring single fiber denier is described in detail. This vibroscope has a least count of 0.01 denier, which corre sponds roughly to about 0.03 μg. weight in a 1-in. sample. The improvements incorporated into this new model pertain primarily to its speed and ease of use. A description of the important parts is included, and some illustrative data are shown.
The Prediction of Equilibrium Thermal Comfort from Physical Data on Fabrics
Authors: Hardy H.B. , Ballou J.W. , Wetmore O.C.
Published: March 2008

The effect of clothing on thermal comfort depends mainly on three factors: the physical properties of the fabric, the air spaces between the body and the fabric, or between the fabrics themselves, and the characteristics of the environment, such as its effective radiative temperature and the temperature, velocity, and relative humidity of the air. All these factors are considered in the development of a theory which permits, in principle, the prediction of the equilibrium thermal comfort associated with any fabric under any specified set of conditions, on the basis of "thermal resistivities" which may be measured with laboratory apparatus. The step-by-step solution of a typical problem concerning the relative comfort ratings of several fabrics is pre sented as an example of the method.
Weight Measurement of Yarn Irregularity
Authors: Chakrabarti B.K.
Published: March 2008

To determine the coefficient of variation of certain characteristics in a yarn, such as the weight in constant short lengths, is a long and tedious task when using the standard root-mean-square method of computing the standard deviation. However, this standard deviation can be quite accurately estimated by any one of three short-cut methods described herein—the mean deviation method, the mean range method, and the probit method. The mean itself, by which this standard deviation is divided to get the coefficient of variation, is obtained readily by weighing all the samples together. The standard errors of the coefficient of variation estimated by these short-cut methods are derived, and the efficiencies of the methods are compared with that of the direct root- mean-square deviation method, showing the corresponding sample sizes for the same efficiency.
Degradation of Cellulose During Mechanical Processing
Authors: Whitwell John C. , Schwenker Robert F.
Published: March 2008

Experimental results and methods of calculation used in investigating the hypothesis of degra dation during mechanical processing [8, 14] are re-examined. New data on a cotton whose processing was entirely standard are reported. An analysis of viscometric measurements, calcu lations, and methods of comparison is included. Methods of another laboratory [1, 4] where this same problem has been investigated are compared. The current results indicate that the original findings [8, 14] are substantiated in concept and magnitude.
Magnetic Anisotropy of Cellulosic Materials
Authors: Loeb L. , Welo L.A.
Published: March 2008

The results of a survey of the magnetic anisotropy of a group of cellulosic materials measured according to the Krishnan "oscillation" method are presented. The technique is described for the application of this method to the measurement of the anisotropy of fibrous materials.

Experimentally it was found necessary to subject the samples to brief pretreatment with cold, dilute acid in order to obtain concordant results for a given material. Data are given to show the effect on the observed anisotropy of variations in this pretreatment.

The results of magnetic anisotropy measurements are discussed as to their possible usefulness in characterizing molecular orientation. It is shown that for materials of a given crystalline modification (cellulose I or II) the observed anisotropy is primarily a function of molecular orientation, but that the anisotropy varies with orientation in a different manner for the two crystalline modifications. The influence of variations in the amount of crystalline material on the observed anisotropy is also briefly discussed.
A Theoretical Investigation of Cap and Ring Spinning Systems
Authors: Crank J.
Published: March 2008

This paper describes how balloon profiles and thread tensions may be calculated, given the requisite properties of the yarn and the spinning frame, by solving the equations of motion of the ballooning thread and by considering the forces acting at the cap edge or on the traveller. It is possible to include the effects of air drag and Coriolis forces by carrying out the calculations on a differential analyzer. The influence of top tension on the balloon profile is investigated in air and in vacuum, and, in particular, the characteristic licking of the cap is seen to be a consequence of air drag and low tension. It is associated with the tendency to form a double balloon at low tensions in vacuum.

Calculated profiles agree reasonably well with those observed for corresponding tensions at the top guide on a practical cap-spinning system. The balloon is shown to be determined by two parameters involving the various technical features such as yarn tension and denier and the dimensions of the spinning frame.

The forces at the cap edge and on the traveller are considered. As an example, the equation at the cap edge is combined with those of the ballooning thread to show how bobbin tension is de creased by increasing the bobbin radius and by decreasing the friction between the cap edge and the yarn. The calculations confirm that licking may arise when the bobbin is full even though it does not occur when it is empty. The bobbin tension calculated for a given bobbin radius, on the assumption of a perfectly smooth cap, agrees well with the observed tension in a practical system.
Crimping of Wool Fibers
Authors: Horio M. , Kondo T.
Published: March 2008

By employing differential staining under controlled conditions and by experiments on resist ance to chemicals, it is shown that wool possesses an inherent bilateral structure which runs the entire length of the fiber from root to tip. The similarity in behavior of wool, as shown in this study, to the formation of crimp in viscose rayon indicates that structural asymmetry may be re sponsible for the coiling and crimping nature of the wool fiber. Isolated single wool fibers show a pronounced tendency to coil; however, when movement is restricted by the proximity of other fibers in a lock or in mass, the result is the formation of crimp.
Relation Between Dyeing Properties of Wool and Modifications of the Fiber
Authors: Lagermalm Gösta , Lindberg Joel , Weissbein Leonard
Published: March 2008

Dye rates were measured for unsteamed and steamed solvent-extracted wool. These meas urements indicate that the dye rates for wool that has not been alkali-damaged, or wool in which the alkali damage has been restricted to the fiber surface, are not influenced by steaming. The dyeing time for wool treated with an aqueous alkaline solution is increased considerably by steaming. This would indicate that the effect of steaming is due to modifications in the bulk of the wool fiber.
A Two-Dimensional Load-Extension Tester for Woven Fabrics
Authors: Reichardt C.H. , Woo H.K. , Montgomery D.J.
Published: March 2008

A two-dimensional load-extension tester for woven fabrics has been constructed. The ap paratus imposes simultaneous extensions on a sample in two mutually perpendicular directions. A strain-sensing element measures the internal strain developed in the homogeneously strained region as a function of the dynamically varying load. Preliminary results indicate important dif ferences in behavior of fabrics under one-dimensional tests and under two-dimensional tests. The latter are believed to simulate better the conditions that a fabric sustains in actual use.
Further Studies on Cotton Cellulose with Reduced Crystallinity
Authors: Segal Leon , Nelson Mary L. , Conrad Carl M.
Published: March 2008

Further studies have been made of the variables in the application of anhydrous ethylamine to cotton cellulose. The crystallinity of the product has been estimated by means of the acid- hydrolysis residue method. Indication of crystallite length has been obtained by the use of the "leveling-off" degree of polymerization. Reduction of crystallinity has been shown to take place rapidly and to be independent of the degree of polymerization of the cellulose. The maxi mum reduction in crystallinity was found to occur in material that was free of tension. Crystal lite orientation was essentially unaffected by the treatment. The cellulose II pattern was always found in the cellulose after contact with mercerizing caustic, regardless of the sequence of treat ment. A crystallite length of 150 anhydroglucose units seems to be a more stable structure after amine treatment than that of 225 units, which is usually found in native cotton.
Properties of Apparel Wools
Authors: Burte Harris M.
Published: March 2008

A description is given of the measurement of the tensile force-extension curves of fiber as semblies with no net twist—i.e., top and roving produced on the French worsted system. Typical force-extension curves are presented, and the effects of testing conditions on various parameters of these curves have been determined. These force-extension curves are a measure of the forces required to cause the fibers to slip over one another; they depend on such factors as fiber length, fiber diameter, fiber modulus of elasticity, interfiber coefficient of friction, and fiber crimp, and on density of fiber packing in the assembly, fiber parallelism, and weight per unit length of the assembly. The relationships between the above factors and parameters of the force-extension curve are discussed in the light of the use of these measurements to investigate processes which affect any of these factors or to characterize different fiber types.

The variability of parameters of the force-extension curve is discussed. Part of the variability may be ascribed to slight differences in the performance of the machine units producing the assemblies.
Impact Properties of Yarns Made from Different Fibers
Authors: Schiefer Herbert F. , Appel Wm. D. , Krasny John F. , Richey George G.
Published: March 2008

Yarns ranging from low tenacity and high elongation to high tenacity and low elongation were broken by impact loading and by static loading. The energy required to break each yarn under impact loading, "impact energy," and under static loading, "static energy" ; the elonga tion at break; and the tenacity were measured or calculated.

The results show that the impact energy to rupture can, in general, be estimated from the static energy. The impact energy greatly exceeded the static value for yarns of low elonga tion. For yarns breaking above an elongation of about 50%, the impact energy was about equal to the static energy, except for two yarns having an elongation of over 500%, where it was less than the static value.

Yarns having a very high elongation when tested at 70°F and 65% relative humidity had greatly reduced elongation when dried for 120 hrs. at 190°F and tested immediately. The elongation was still further reduced when the dried yarns were cooled for 1 hr. at — 40°F and tested immediately.

These findings have a bearing on the selection of yarns for the construction of safety belts, safety ropes, and certain aeronautical textiles which may be subjected to impact loading over a wide range of temperatures.
A Single-Fiber Load-Elongation Tester for Cotton
Authors: Orr Rollin S. , Grant James N.
Published: March 2008

A single-fiber tester of the type employing a constant rate of loading is described. Designed especially for obtaining load-elongation curves in addition to end-point data on cotton fibers, it employs coiled-spring loading and optical means of recording. Devices are incorporated that permit cyclic loading studies and static life determinations. An oven and humidification tank are provided for testing at various temperatures and under various moisture conditions.
Effect of a Wetting Agent on the Hydrolysis of Highly Methylated Cotton Cellulose
Authors: Reeves Richard E. , Barrett Bernard J.
Published: March 2008

The acid-catalyzed, heterogeneous hydrolysis of a highly methylated cotton cellulose has been investigated, with particular attention to the effect of incorporating a wetting agent in the hydrolysis medium. It was found that the amount of fast-reacting material was small when the aqueous acid did not contain a wetting agent, but was increased severalfold in the presence of an active wetting agent. The rate constant for the slow-reacting material was also increased by the wetting agent. The minimum viscosity reached during hydrolysis was the same in the presence or in the absence of the wetting agent.
Modification of Wool by the Application of Linear Synthetic Polyamides
Authors: Jackson D.L.C.
Published: March 2008

The presence of foreign materials such as soaps and oils on wool interferes with the deposi tion of N-alkoxymethyl polyamides when used for the prevention of felting shrinkage.

If the wool is rigorously cleaned by ethanol extraction or if the fiber surface is modified by pretreatment with hydrogen peroxide or other reagent, then the resin is able to attain its maximum effect and approximately 3% resin (based on the weight of the wool) is sufficient to prevent felting shrinkage.

It is suggested that both forms of pretreatment tend to improve adhesion between resin and fiber and so render the resin deposit more effective in preventing felting.