bluuebunny/crossref_metadata_2025_split huggingface dataset:
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
some Observations on the Reaction of Modified Keratins with Nitroprusside
Authors: Ripa O. 
Published: March 2008

The sulfhydryl groups of treated keratin differ from those of ordinary thiol compounds in their reactivity toward sodium nitroprusside—they often do not give the characteristic red-violet coloration in slightly alkaline aqueous medium. Among the several modifications of keratin investigated, only keratin treated with thio glycollate gave a positive reaction. In all other cases, however, a positive reaction could be obtained if it was carried out in concentrated guanidine hydrochloride solution. This medium should therefore be used to prove the presence of sulfhydryl groups in treated keratin. The application of the nitroprusside reaction in both of these media showed that the treat ment with thioglycollate differed from other cases in that it produced two kinds of sulfhydryl groups. Some of the groups reacted with nitroprusside in an aqueous medium, while some did so only in guanidine hydrochloride solution. Similarly, the detection of the disulfide groups of untreated keratin by means of potassium cyanide and nitroprusside should also be brought about in concentrated guanidine hydrochloride solution, because the color does not appear in aqueous medium. At temperatures of 65° and 100°C, according to Phillips et al., the treatment of wool with aqueous solutions of potassium cyanide leads to an almost quantitative conversion of the com bined cystine into lanthionine. However, such wool also gives a strong coloration with nitro prusside in guanidine hydrochloride solution. This cannot be caused by lanthionine, and is therefore in contradiction to the assumed quantitative nature of the formation of lanthionine under the specified conditions.
Experiments with an Alkali Swelling-Centrifuge Test Applied to Cotton Fiber
Authors: Marsh P.B. , Merola G.V. , Simpson M.E. 
Published: March 2008

A quantitative technique has been developed in which a weighed sample of cotton fiber is swollen in sodium hydroxide, centrifuged to remove liquid from between the fibers, and re weighed to determine its percentage increase in weight, the latter quantity being designated here as the fiber's "alkali-centrifuge value." The results obtained have been found to be related to two types of causal factors—namely, (1) the prior action of deteriorative agencies on the fiber, apparently especially on the outer wall of the fiber, and (2) the wall thickness of the fiber (as reflected in arealometer air-flow measurements). The fiber-deteriorative agencies which have been shown to bring about changes in the alkali-centrifuge value of cotton fiber include micro-organisms, certain enzymatically active filtrates from microbial growth media, sodium hypochlorite, hydrochloric acid, heat, and weathering. The microbial and enzymatic effects have been studied in more detail than the others. The new test is simple, rapid, inexpensive, quite highly reproducible, involves only standard laboratory equipment, and is essentially free from safety hazards to the operator. Several aspects of the methodology of the test are reported.