bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Light on the ESR Spectra of Dyed Cottons
Authors: Baugh Peter J. , Hinojosa Oscar , Mares Trinidad , Hoffman Milton J. , Arthur Jett C. 
Published: March 2008

It was demonstrated, by using electron spin resonance (ESR) 'methods, that free radicals are produced in purified and dyed cotton celluloses by the action of light. Cottons were dyed with 24 different dyestuffs selected from eight broad classifications: direct dyes (either low or high in light-fastness; after-treated with CuSO 4 or diazotized and developed), soluble ester vat dyes, and vat dyes applied by the hot-pigment method, sulfur dyes, and naphthols. Some of the copper-containing dyestuffs and cottons dyed with these materials gave EPR signals with broad line widths. Most of the other dyestuffs used and dyed cottons gave narrow singlet ESR spectra before irradiation with the intense source of light; this indicated that the natural light interacted with the dyestuffs and with dyed cottons to form free radicals. On irradiation of the dyed cottons with the intense source of light, narrow singlet ESR spectra were also obtained; the signal strengths of these spectra were greater than those which resulted from the interaction of natural light with the dyed cottons. In most cases, the increases in the signal strengths of the spectra observed for the dyed cottons on irradiation were several times greater than the increase observed for purified cotton on irradiation. There was no obvious correlation between the interaction of light with the dyed cottons, as indicated by changes in their ESR spectra and the weather resistances of 'these cottons. This indicated that the energy absorbed by the dyed cottons from both natural and intense sources of light was not necessarily localized, so as to cause depolymerization of the cellulose molecule and consecluent loss in breaking strength of the yarn.
Some New Observations on the Effects of Mild Shrinkproofing Treatments on Wool Fibers
Authors: Makinson K. Rachel 
Published: March 2008

When wool fibers which have been shrinkproofed by either the KMnO4/salt process or a dry chlorination process are examined with the optical microscope, normally, very little effect of the treatment can be seen. However, if they are straightened for the examination, a number of differences between treated and control fibers can easily be seen, especially if water is present. The principal effects are that the scales on the treated fibers, but not on the untreated, become less prominent as the fibers are straightened and that this change is much greater on the side which was the intrados of the crimp curve than on the extrados. Microscopic observation of fibers sliding on each other or over a diffraction grating also reveals effects of the treatment: the deforma tion of the scales of treated fibers is more plastic and less elastic than that of untreated and the sliding of the treated fibers is more heavily damped. From these and other observations, the conclusion has been drawn that these treatments degrade the protein inside the scales so that it becomes more viscous and less elastic, particularly when it is swollen by or dissolved in water. The epicuticle appears to be unbroken and still elastic. These results throw some light on the well-known disagreement between different workers about the changes produced in the coefficients of friction of wool fibers by the KMnO 4/salt treatment. 1 In the comprehensive study of crimp recovery by Banbaji et al. [Textile Res. J. 32, 568-572 (1962)], the fiber was allowed to contract slowly and continuously. The observa tions described here refer essentially to discontinuous re covery.
The Effect of Drawing-Frame Variables on Cotton Fiber Hooks and Parallelization and Processing Performance
Authors: Simpson J. , Sands J.E. , Fiori L.A. 
Published: March 2008

A study was made of the effect of the drawing frame variables, sliver weight, total draft and doublings, draft distribution, back roll setting and weighting, and top- bottom second roll spacing on fiber parallelization, fiber hooks, and processing per formance. Sliver weight had a significant effect on fiber hooks, fiber parallelization, and processing performance, whereas the other processing variables had little practical effect, even though the effects observed were in many instances statistically significant. Fiber hooks increased and fiber parallelization decreased as the sliver weight fed to drawing increased. This led to an increase in spinning end breakage. An increase in draft and doublings increased fiber parallelization, but decreased sliver uniformity. The increase in fiber parallelization overshadowed the decrease in sliver uniformity, resulting in a decrease in spinning end breakage. These findings demon strate the need for achieving fiber parallelization, as well as sliver uniformity measure ments, to develop processing organizations that will result in optimum processing per formance and improved quality control.
Gel-Permeation Properties of Cellulose
Authors: Blouin F.A. , Martin L.F. , Rowland S.P. 
Published: March 2008

The gel-permeation technique has been applied to the characterization of cotton cellulose fibers from fabrics cross-linked with formaldehyde in wet-cure and in bake-cure reactions and reduced to a sufficiently small particle size by Wiley-milling. Measurements of total internal water contents, internal solvent volumes, and permeability limits are indicative of the nature and extent of changes in pore structure resulting from the cross-linking. Cross-linked compositions were examined at progressively higher levels of formaldehyde which were obtained under the various reaction conditions. The wet-cure processes Forms W and W' involving water-swollen cotton produced only limited alterations of the cellu lose pore structure at the maximum levels of cross-linking attainable by these treatments. Changes in the values obtained for the gel-permeation parameters were small, but the trends show that a larger reduction of internal pore volume is pro duced under the Form W process than under the Form W' process. Reaction with the less concentrated Form W reagents caused a smaller decrease in the permeability limit than Form W'. Large changes in pore structure resulted from cross-linking the cotton in a collapsed state by the hake-cure, Form C. process. The internal pore volumes of both the total and of the effective solvent water contents were reduced with cross- linking over the range from 0.47% to 2.20% methyleneoxy contents of the samples. The permeability limit was reduced from a molecular weight of 2430 for untreated cotton to approximately 1250 at the lowest level of cross-linking. No further decrease of this parameter was produced by cross-linking up to the maximum methyleneoxy content of 2.20%. In all three forms of reaction, the changes produced in total internal water contents followed trends similar to the values for water of imbibition determined by centrifuging. The latter values were larger than those measured chromatographi cally by 34-100%, the discrepancies being larger for the smaller true volumes of internal water calculated from column- volume measurements. The centrifugal technique of determining water of imbibition is a simple procedure for estimating relative changes of internal pore volumes of cottons.
Preliminary Studies of the Fractography of Fibers and Other Polymeric Materials in the Scanning Electron Microscope
Authors: Mckee A.N. , Beattie C.L. 
Published: March 2008

This paper describes a manipulative stage which can be used to vary the strain applied to fibers, yarns, fabrics, or films within the evacuated specimen chamber of a Cambridge Stereoscan SEM. In another similar stage, an object can be twisted or rotated about its axis so that its complete periphery may be examined. Some of the problems encountered, such as the difficulty in maintaining a conductive surface, are considered. Qualita tive observations of the fracture characteristics of some types of natural and commercial man-made fibers strained in tensile, loop tensile, and knot tensile tests are presented, as well as some observations on fibers subjected to twisting forces. Finally, observations on the tearing,of a photographic film are recorded.
Diffusion and Copolymerization of Polyacrylic Acid in Nylon 66 Fibers
Authors: Arons Gilbert N. , Peirent Robert J. , Macnair Richard N. 
Published: March 2008

Polyacrylic acid (PAA) was applied to a plain-weave nylon 66 fabric from solution at an elevated temperature and pressure. Excess solution was squeezed out and the fabric was oven-dried, heat-cured, and hot water-scoured. The weight of PAA, up to 6% fixed to the nylon, varied inversely with the pH of the PAA solution. Cured fabric with 6% fixed PAA, when converted to the sodium and potassium salts, had moisture regain values comparable to those for cotton. The calcium salt increased the melting temperature of the nylon. Cross sections, of yarns teased from this fabric, stained with a cationic dye revealed that PAA had penetrated the in dividual fibers. This type of polymer diffusion has not been reported previously. The PAA-nylon product isolated from the cured fabric differed from the reactants in solubility, thermal characteristics, and ir absorption. These facts suggest that the PAA had reacted chemically with the nylon. Less PAA reacted when the amine end groups of nylon were blocked, indicating that, in addition to a block copolymer, a graft copolymer formed.
Poly (1, 3, 4)-Benzimidazole
Authors: Ross Jack H. , Schulman Stanley , Stanton Robert M. 
Published: March 2008

Fibers formed from poly(1,3,4)-benzimidazole (PBI) have been spun, using the cotton system, into yarns and woven into a series of plain- and twill-weave fabrics. The high moisture regain (10-13%), good abrasion resistance, and high degree of heat-blocking, in addition to nonflammability in air, has resulted in PBI being considered for Air Force personnel protection systems. Laboratory and field evaluation of PBI fabrics in protection system configurations compared to currently used fabrics demonstrated the superior nonflammability of PBI. Based on data obtained, extensive wear testing of flight coveralls is to be initiated.
The Mechanics of Bicomponent Fibers
Authors: El-Shiekh Aly , Bogdan J.F. , Gupta R.K. 
Published: March 2008

An analytical approach has been adopted to predict the amount of bulk that would develop in a hicomponent fiber having particular geometric distribution of the components of known physical properties. Theoretical expressions have been developed to predict the geometry and mechanical properties of bicomponent struc tures. In particular, an analytical relation has been developed for the radius of the loop of such a structure in terms of strains in the components and their physical dimensions and elastic moduli. The radius of the loop has been related to the bulk ratio. Expressions have also been derived to predict the load elongation relation for the coiled bicomponent structure
Temporary and Permanent Fiber-Friction Increases Induced by Corona Treatment
Authors: Thorsen Walter J. 
Published: March 2008

"Frictionizing" textile fibers by corona treatment produces larger effects than conventional chemical methods. A marked increase in wool fiber friction occurs, both with and against the scales. For wool, the increase in with-scale fric tion decays slowly with time after treatment; against-scale friction does not. Initial cohesiveness of air-corona treated wool roving increases 230%, but then, reflecting the decay of with-scale single-fiber friction, decreases slowly with time toa residual cohesiveness 32% above that of untreated roving. Residual cohesiveness is responsible for improved wool yarn spinnability and tensile strength. Untreated mohair fiber friction is much less than that of untreated wool, but after corona treatment the friction values become comparable. However, treated mohair differs from treated wool in that its with-scale friction after treatment does not decrease. Increased mohair fiber cohesiveness improves yarn tensile strength 31% Injection of dilute chlorine gas into the reactor greatly reduces the required corona treatment time and indicates the feasihility of high-speed corona processing of mohair. Cotton roving cohesiveness is increased initially by chlorine-corona treatment to four times its original value, but then its cohesiveness diminishes much more rapidly than in the case of wool. The residual cohesiveness increases cotton yarn tensile strength by 24%. It appears that the very high cohesiveness of wool and cotton roving immediately after treat ment, if followed by immediate processing, can be used to further improve spinning beyond that achieved when treatment is followed by delayed processing.
Soiling Properties of Wool Fabrics
Authors: Benisek L. , Crawshaw G.H. 
Published: March 2008

Laboratory soiling and cleaning trials on nine different fibers in woven fabrics of comparable construction revealed that wool has better overall soiling properties than manmade fibers. Finer wools become soiled more easily than coarser wools; finer yarns soil less than coarser yarns; and resistance to soiling is also slightly improved by higher yarn twist. Soil release and soil redeposition of wool fabrics are only slightly - influenced by fiher fineness, yarn twist, and yarn count. With increasing cover factor, the knitted fabric soils less, because of the tighter construction, but soil release is inhibited slightly. The effect of fiber, yarn, and fabric construction on the scattering coefficient and its influence on "visible" soiling is discussed. By suitable choice of yarn and fabric construction, the soiling properties of wool garments can be noticeably improved.
Soiling Properties of Wool Fabrics
Authors: Benisek L. , Crawshaw G.H. 
Published: March 2008

Chemical degradative processes used for shrink proofing treatment improve significantly the soiling properties of wool, presumably by smoothening the fiber surface and increasing its hydrophilic properties. The improvement depends on the level of shrink resistance. Resin-shrinkproofing treatments often impair the good natural soiling properties of wool, depending on the surface energy, hardness, and zeta potential of the resin. Bleaching wool by hydrogen peroxide also improves significantly its resistance to soiling and ease of soil release in wash ing. Reductive bleaching has a slightly lower beneficial effect. Flat-setting treatments with reducing agents also slightly improve the soiling properties of wool fabrics. In order to obtain the optimal soil release properties in washing, the pH of wool and the washing liquor should be > 7. The oil content of wool fibers has an important influence on soiling, increasing soil retention and improving soil release in washing or dry-cleaning. From the point of view of soiling, wool garments should not have more than 0.5% oil content. Due to their strongly hydrophobic properties, water-repellent agents, with the exception of fluorocarbons, significantly impair soiling, desoiling, and soil redeposition in washing. Block copolymers of fluorocabrons and polyethyleneoxides are the only repellents which do not impair the good, natural soiling properties of wool. In fact, they possess a certain degree of soil repettency.
Fibrous Structure Formation in Cold-Drawing of Polyethylene
Authors: Muzzy John D. , Hansen David 
Published: March 2008

Rods of spherulitic, linear polyethylene were cold-drawn at 60 and 100°C and the morphology of the drawn material, particularly the necked portion, was characterized by light and electron microscopy and by wide- and small-angle x-ray scattering. The drawing proceeded by neck formation and propagation at a draw ratio of 10. Further extension or creep beyond the neck produced draw ratios up to 20. Neck formation was characterized by spherulites deforming essentially in concert with the macroscopic deformation, becoming elongated and oriented and, thereby, defining a gross fibrous structure. Very early in the process of neck formation, small disruptions appeared within the spherulites. Similar to crazes in amorphous materials, these disruptions measured a few microns long, perpendicular to the direction of deformation, and a fraction of a micron thick. The disruptions increased in size and number as drawing progressed, dominated the structure at the higher draw ratios, and oriented to define a fine, fibrillar structure. These observations are contrasted with the rather different results obtained in an earlier, similar study of the cold-drawing of nylon 66.
A Rapid and Reproducible Method for the Determination of Dry-Soil Resistance
Authors: Kissa Erik 
Published: March 2008

A rapid and reproducible method is described for measurement of adsorption of particulate solids on fabrics or films and evaluation of dry-soil resistance. An Accelerotor drives the soil and samples along a circular path within a chamber. Impingement and degree of soiling can be continuously varied by changing the speed of the Accelerotor, the duration of soiling, and the amount of soil. Soiling values of the new method correlate with soil resistance data obtained by other soiling methods involving me chanical work, such as tumbling and rubbing. A correlation exists also with nonabrasive soiling of stationary fabrics, unless the construction of the fabrics is markedly different or the transport of soil to the fiber surface determines soiling. Simultaneous soiling of different fabrics was found to be competitive. Fabrics with the least soil resistance were preferentially soiled at the expense of the more soil-resistant fabrics. This alternative procedure has been used to enhance soil-resistance differences for visual evaluation. It is shown that the resistance of a fluoropolymer-trealed fabric to oily particulate soil is not a function of its oil repel lency, but depends upon the nature of the polymeric finish, the substrate, and surface coverage.
Synthesis of Chlorodeoxycellulose and its Conversion to 5,6-Cefluloseen
Authors: Srivastava H.C. , Harshe S.N. , Gharia M.M. 
Published: March 2008

Reaction of cellulose acetate with methylsulfonyl chloride in N,N-dimethylformamide has been studied under different conditions of time, temperature and concentration of the reagent. Using this method, chlorodeoxycellulose of a D.S. as high as 0.58 has been prepared. The reaction has also been applied to purified cotton linters to yield chlorodeoxycellulose. Attempts to prepare this cellulose derivative by reaction of cellulose acetate with acetyl chloride, anhydrous aluminum chloride and magnesium chloride in N,N-dimethylformamide were unsuccessful. 5, 6-celluloseen is obtained by dehydrohalogenation of the chlorodeoxycelluloses either with dry methanolic potassium hydroxide or with potassium tert. butoxide in dimethyl sulfoxide. With the latter reagent the conversion of chloro deoxycellulose to celluloseen is almost quantitative.
Adsorption of Particulate Solids on Textiles1
Authors: Kissa Erik 
Published: March 2008

Adsorption uf particulate solids and synthetic soil on cellulose and synthetic fabrics has been studied by a dynamic method involving high speed rotation of the solid and the substrate in a closed chamber. The results confirm that adhesion, and not mechanical entrapment, is the dominant soiling mechanism. Adsorption of particulate matter on the fiber surface increases with increasing pressure and mechanical work done during the soiling process. Some desorption of already adsorbed solid particles occurs because of abrasion; fibers with a higher toughness index retain adsorbed particles more firmly. The amount of particulate matter adsorbed on the fabric increases with the increasing amount of soil contacted with the fabric. A linear log-log plot of the two amounts resembles formally the Freundlich adsorption iso therm. The amount of soil adsorbed increases linearly with the logarithm of soiling time; the kinetics are apparently of second order. A linear relationship exists also between the amount of soil adsorbed and the reciprocal of rotational velocity of the impeller driving the solid and the substrate. It is shown that fabrics with different construction respond differently to the mechanical action of the soiling process. The geometry of the fabric can be a more important factor determining soil resistance than the chemical composition of the fiber. A surface film of either hydrophilic or hydrophobic liquids on hydrophilic or hydrophobic fibers increases soil adsorption.
Assessment and Analysis of the Bellows Ventilation of Clothing
Authors: Vokac Z. , Køpke V. , Keül P. 
Published: March 2008

A methodical approach is described, attempting to separate the loss of heat and moisture due to forced exchange of air inside clothing, when walking, from the loss caused by gradients between the body and the environment.Temperature, heat flow, and relative humidity were recorded on the skin of the back and inside the respective clothing (shirt only, vest and shirt, or vest, shirt and anorak) in 12 experiments performed in a climatic chamber at 4-11°C and 35-70% RH, The subject walked on a treadmill with 5% grade at 7.2 km/hr until a new steady state of higher tempera ture and heat flow, as well as humidity, resulting from evaporation of sweat, was reached. When the motion was suddenly stopped, both the temperature and humidity increased steeply, while the heat flow decreased, showing levels which would have been attained, theoretically, if the transfer of heat and water vapor along gradients was not assisted by forced exchange of air when walking. When walking was resumed after a pause, all recorded parameters changed in the opposite direction. Continuous recording of temperature next to skin showed temperature oscillations synchronous either with every step or with every other step.The results are considered as evidence of the effect of forced ventilation on the microclimate. Calculated from changes in water-vapor pressure, the magnitude of forced ventilation corresponded, approximately, to dilution of the air layer next to skin, with atmospheric air, by one-half of its volume.It was demonstrated, in addition, that the heat of sorption, arising from transient increases of humidity in the clothing, had a marked effect on temperature of the micro-climate.The term "bellows ventilation" is thought to express best the mechanism of exchange of air resulting from rhythmical movements of limbs and body at physical activity.
A Study of Some Factors Affecting the Photodegradation of Textile Yarns Part I : The Spectral Distributions of Sun-Sky and Xenon-Arc Radiation
Authors: Lock Leona M. , Frank Grace C. , Stevens J.R. 
Published: March 2008

A detailed study was made of the relative spectral distribution of sun-sky radiation at several times of day under various sky conditions from June to October 1971. A sufficient number of spectra were recorded to provide a statistically viable sample. Average spectral distributions for three daily time periods and four classes of sky conditions within four approximately monthly periods were calculated and compared. Radiation from a sunny-bright sky over the noon period gave a representative average and would be a reasonable standard sun-sky spectral distribution for comparison with artificial light sources. The relative spectral distribution of xenon-arc radiation in combination with various filters was monitored using the same spectrographic equipment. Comparison of the sun-sky spectral distribution with the xenon arc emission spectrum indicated that although agreement of the lower cut-off wavelength could be attained using Q/Q/WG filters. Xenon radiation was deficient above 3150 Å regardless of the filter system used. Infrared filters removed an undesirable amount of high energy radiation and would be likely to decelerate degradation.