bluuebunny/crossref_metadata_2025 huggingface dataset:
Submicroscopic Structure of Cellulose from Nitrogen-Sorption Measurements
Authors: Hunt Charles M. , Blaine Raymond L. , Rowen John W.
Published: March 2008

When cotton linters were soaked in cold 10% sodium hydroxide, washed and neutralized, transferred successively to methyl alcohol and benzene, and carefully dried at reduced pressure, a surface area as great as 71.3 sq. m. per g. was obtained by the Brunauer-Emmett-Teller tech nique. Previously obtained areas for untreated cotton were all less than 1 sq. m. per g. Linters carried through the above steps after soaking in water instead of in alkali had areas as great as 47.3 sq. m. per g. When the alkali-treated sample was conditioned in water vapor to a 3.3% gain in weight, the surface decreased to 31.6 sq. m. per g.; further conditioning to an 11.0% gain in weight decreased the surface to 2.1 sq. m. per g.

The isotherms of the treated samples showed strong hysteresis, while the isotherms of untreated cotton showed little or no hysteresis.

Calculations of pore-size distribution by the method of Wheeler and Shull indicated that these materials have rather narrow distribution ranges, the alkali-treated material having a maximum at a pore radius of about 20 Å. and the water-soaked material a maximum at about 16 Å.
Types and Dimensions of Fiber Scales from the Wool Types of Domestic Sheep and Wild Life
Authors: Mahal Gurbax Singh , Johnston Alexander , Burns Robert H.
Published: March 2008

Scale structure and dimensions and fiber thickness were measured on a number of fibers repre senting the different fiber types from fleeces of several wild life species, including the Big Horn sheep, and of fibers from the various wool types of domestic and primitive sheep, including the fine-wool, medium-wool, long-wool, and mixed-wool types. The scale index, or relation of scale height to fiber thickness, was studied as a means of identification of fiber types and as a breed characteristic. The relationship between scale structure and dimensions in the various animal textile fibers and the identification of the animals from which the fibers came were studied.
Correlation Studies of Accelerated and Natural Weathering Tests of Protectively Finished Cotton Duck
Authors: Fynn P.J. , Daly Catherine N. , Fleming Constance M. , Dean J.D.
Published: March 2008

Artificial and natural weather exposure tests were made with unfinished and with protectively finished cotton duck samples. The treating agents employed were chiefly mineral pigments, film-forming resins, and vat dyes, alone and in combinations.

The finishes were ranked in order of excellence on the basis of amounts of original strength retained by individual samples in both types of exposure.

The results of the natural and accelerated tests were compared and then correlated by a statistical method and by a simple computation of agreement among groups of good, intermediate, and poor performance. Although statistical interpretation of the data indicated a positive corre lation between the 2 types of tests, the relationship was not sufficiently constant to justify reliance on the accelerated techniques employed in predicting the behavior of finished cotton textiles in outdoor service conditions.
C avitomic Cotton
Authors: Hall Laura Thomas , Elting John P.
Published: March 2008

Damage resulting from microorganisms occurring in increasing amounts of apparently good spinnable Middling cotton and the effects on mill processing are recognized. Such cottons, called "cavitomic," are distinguished from off-color and field-damaged types. Data and obser vations supporting a previous publication, together with methods of observation, are given. Reducing-material content, pH, and metallic-ion content of easily soluble water extracts are dis cussed, and relationships between them shown. Weakening of the fiber is exhibited by shorten ing of staple. Data obtained under both laboratory-controlled and conventional warehouse- storage conditions are given.
Modification of Wool by the Application of Linear Synthetic Polyamides
Authors: Jackson D.L.C.
Published: March 2008

The effect of surface deposits of N-hydroxymethyl polyhexamethylene adipamide on the felting shrinkage of wool has been determined. These polymers resemble the N-methoxymethyl poly amides in that the polymer itself is not particularly effective in preventing felting shrinkage of wool, but when the substituted polymer is applied to wool fabric and then converted to the un substituted polyamide on the fabric, its effectiveness in reducing felting shrinkage is very much increased.

A deposit of approximately 3% by weight of polymer on the fabric has been found to eliminate entirely felting shrinkage of the fabric under the test conditions. The optimum degree of sub stitution of the polyamide for production of non-feltability is similar to that found for the N- methoxymethyl derivatives— vi., between 20% and 25% -NH groups substituted.

The N-hydroxymethyl polyamides can be converted to the unsubstituted polymers either by hydrolysis—e.g., with acids—or by heating in air.
Effect of a Dynamic Fatigue Test on the Mechanical Properties of Tire Cords
Authors: Grant James N. , Couturier Geraldine M. , Rhodes Mary W.
Published: March 2008

Changes in the mechanical properties of cords subjected to dynamic fatigue were measured for cotton, mercerized cotton, and rayon tire cords. These data were obtained by the use of an instrument which subjected the cords under tension to localized dynamic forces under con trolled atmospheric conditions. The forces, when observed on an oscilloscope screen, were found to vary during the flex cycle. Flex life and ultimate elongation were found to be cumulative, regardless of whether the cords were fatigued continuously or were allowed to relax with or without static tension between periods of flexing. Calculated activation energies for fatigue failure were less than those for heat degradation. From the differences in properties a quali tative evaluation of tire cord behavior could be made.
Microscopical Observations on the Contents of the Cotton Fiber Lumen
Authors: Catlett Mamie S. , Giuffria Ruth , Moore Anna T. , Rollins Mary L.
Published: March 2008

A method is described for isolating the lumen contents of the cotton fiber by digestion of the cellulose in chilled 72% sulfuric acid. Microscopical observations on the isolated "lumens" as well as the lumen in the whole fiber are reported. The isolated lumens appeared tubular in shape, and electron micrographs of thin sheets of the membrane material showed an unoriented, granular structure.

The lumen residue isolated by sulfuric acid was found to be completely hydrolyzed by 1% sodium hydroxide, but only partly hydrolyzed in dilute mineral acid. Amino acid determination by paper chromatography disclosed no free amino acids in the lumen material; but in an acid- hydrolyzed sample, glutamic and aspartic acids, valine, alanine, and probably serine and arginine were found, in addition to several unidentified amino acids.
Some Properties of Thermoplastic Fiber-Bonded Fabrics
Authors: Wrotnowski Arthur C.
Published: March 2008

Test procedures and physical properties are given for cotton, nylon garnett, asbestos, and glass fiber thermoplastic fiber-bonded fabrics. A range of thicknesses for each blend and weight is used to demonstrate a wide variety of fibrous constructions. The tensile strength, air perme ability, and water absorption characteristics of four fiber-bonded fabrics are discussed. It is indicated that any textile fiber can be fabricated by this process.
Analysis of Staple Fiber Mixtures
Authors: Fisher D.C. , Roberts E.D.
Published: March 2008

Methods were developed for the qualitative and quantitative analyses of staple fiber blends con taining acetate, dynel, wool, nylon, viscose rayon, cotton, Orlon acrylic fiber, and Dacron poly ester fiber in any combination. The qualitative analysis involves determination of density and microscopic appearance; the quantitative analysis employs selective solvents.

The methods presented in this paper are suitable for the analysis of most blends in use at the present time. The nature of the methods presented is such as to permit extension by suitable modification for use in the detection and determination of other fibers also.
Development of a Sewability Test for Cotton Fabrics
Authors: Frederick E.B.
Published: March 2008

The development of the seam efficiency test to measure the sewability of a fabric is described. It is shown that this test, which involves the establishment of a ratio between the strength of the original fabric and the strength of the seamed fabric, is more realistic, reproducible, and sensitive than the previous test, which rated a fabric for sewability on the basis of the number of fabric yarns cut per inch during the sewing operation.
Viscometric Studies of Cellulose in Cotton in Relation to Mechanical Processing
Authors: Conrad Carl M. , Rusca Ralph A.
Published: March 2008

A study was undertaken at the Southern Regional Research Laboratory to determine whether or not the mechanical processing of cotton fibers into yarn causes any chemical degradation to the cellulose. The study seemed timely in view of a report [22] indicating that the mechanical processing of cotton into yarn by conventional textile machinery causes as much as 30% average reduction in intrinsic viscosity.

Studies were made on four sets of samples which had been treated as follows: ( 1) powdered in a Wiley mill; (2) processed a number of times through a new type of textile cotton opener developed at the Southern Regional Research Laboratory; (3) mechanically processed in essen tially the same manner as in the study referred to above; and (4) portions of the same samples used by Krieble and Whitwell [22].

The viscosity measurements determined by the methods employed at the Southern Regional Research Laboratory failed to show any demonstrable chemical damage to the cellulose which could be associated with processing. When the new method described by Krieble and Whitwell was applied to the viscosity data, the linear plots depended upon for extrapolation could not be obtained.

It was concluded that the damage previously reported to have been found is not fully supported by a statistical treatment of the data; also, that chemical damage is not produced in ordinary cotton textile processing to any appreciable extent, although it might conceivably become notice able in excessively processed cotton. Some suggestions are given to explain the failure to secure linear plots by the suggested new method.
Relationship Between Various Surface Properties of Wool Fibers
Authors: Lindberg Joel
Published: March 2008

Wool fibers were treated with alcoholic potash for different periods of time. The anti-scale and with-scale coefficients of friction were measured by means of a modified fiber twist friction meter. The with-scale friction increases with time of treatment, and this is explained in terms of a chemical modification of the epicuticle. There is a close relationship between friction and breaking strength of top and between friction and felting rate.
The Plasticity of Wool
Authors: Burley R.W. , Speakman J.B.
Published: March 2008

The variations in plasticity among the fibers of single staples of New Zealand Lincoln, New Zealand Romney, and Australian merino wools are associated with follicles of different types and ages. Primary follicles produce fibers of lower plasticity than those of secondary follicles, and the order of plasticity of the fibers is, in general, the inverse of the order of development of the follicles.
Force-Temperature Behavior of Nylon Filaments at Fixed Extensions
Authors: Bryant George M.
Published: March 2008

By use of the thermodynamic equations for elasticity, force-temperature measurements on nylon filaments at fixed extensions in water have been related to the molecular mechanism of elasticity. Drawn fibers at low extensions were found to have an entropy force component larger than the total force. This effect was less pronounced in undrawn fibers, but persisted over a wider range of extensions. For undrawn nylon, a transition in the force-temperature behavior has been found which differs markedly from the second-order transition in rubber; rubberlike elasticity was found below rather than above the transition temperature. The transition temperature was ca. 47°C for 5% extension, and increased rapidly with increasing extension. Both nylon 6-6 and nylon 6 were found to have the same force-temperature be havior, except that the former showed evidence of impending glasslike elasticity near 0°C.
Improvement of Luster of Cotton
Authors: Fourt Lyman , Rutherford Marjorie B.
Published: March 2008

One of the means of increasing luster, which is available to designers working in any fiber, is variation of weaving pattern or construction. It is examined here for comparison with other means of improvement which are more specifically applicable to cotton. The increase in luster in going from plain weave to a 4/1 float is considerable; a 4/1 float is significantly higher in luster than a 3/1 float, all at constant texture, with the same yarns.

Sheerness obtained either by finer yarns or decreased texture also increases luster. How ever, if cover is kept constant by using more of the finer yarns, the two tendencies oppose each other, reducing the change of luster.
Tensile Properties of Bristle Fibers Made from α- and β-Casein
Authors: Hipp N.J. , Groves M.L. , McMeekin T.L.
Published: March 2008

The tensile properties of fibers made from α- and β-casein and unfractionated casein have been compared. β-Casein fiber, oriented by stretching, was considerably better than the other casein fibers, and values for its wet and dry tenacity compared favorably with corresponding values for wool. The better fiber properties of β-casein are ascribed to its molecular structure.
Modification of Wool by the Application of Linear Synthetic Polyamides
Authors: Jackson D.L.C.
Published: March 2008

N-alkoxymethyl polyamides may be applied to wool from aqueous dispersions containing a surface-active agent. If an anionic agent is used, the resin can be deposited on the wool by the addition of acid. For efficient deposition, the resin-detergent ratio must be chosen such that: (a) the net charge on the resin-detergent particles is opposite in sign to the charge on the fiber surface, and ( b) the amount of detergent is insufficient to interfere with the nonfelting action of the resin. Using a sodium secondary-alkyl sulfate as anionic detergent and a resin-detergent weight ratio of 20 :1, ethoxymethyl nylon has been applied to wool fabric from aqueous dispersions at approximately pH 2.5. The felting shrinkage of the fabric can be reduced appreciably by depositing about 6% resin on it in this way.
Crossbonding of Casein Bristle Fiber
Authors: Peterson R.F. , McDowell R.L. , Harrington B.J.
Published: March 2008

A method is described for reducing the rate of water uptake of casein fibers and plastics. The method involves treating formaldehyde-hardened casein products with resorcinol and formaldehyde, drying, and heating. Optimum conditions for this treatment are described. The results indicate that resorcinol forms crossbonds with casein and formaldehyde.
The Improvement of Luster of Cotton
Authors: Fourt Lyman , Elliott H.J.
Published: March 2008

The range of increase of luster from the application of thermosetting resins in a cotton twill is found to be as large as that produced by mercerization and to be generally similar in ap pearance. Further increases in luster, as measured by contrast ratio, can be obtained by high pressure embossing, although the appearance of the embossed areas is different and can be recognized as flattened.

Various types of urea formaldehyde and melamine formaldehyde resins are very similar in their effects on the luster of cloth, and variations in mechanical smoothing similar to tentering or light calendering have more influence on luster than the type of resin. The resins do differ, however, in their effect on wrinkle recovery, stiffness, and tensile and tear strength.

Thus it appears that the chief effect of thermosetting resins on luster of fabrics is indirect, through their durable control of fabric structure. The direct effect of the resins on luster, as shown by tests on yarns, is to decrease the luster of mercerized cotton and only slightly to in crease the luster of nonmercerized cotton.
Properties of Apparel Wools
Authors: Burte Harris M.
Published: March 2008

Mechanical properties derived from the force-extension curve, and including tensile recovery, have been measured for single strands of steamed worsted yarn throughout their aging at 65% R.H. and 70°F. None of these properties appears to change significantly throughout an aging period of several months.

Measurements on single strands of unsteamed yarn which are permitted to untwist prior to test indicate a progressive change in physical properties with time of aging. This is caused by a slow setting-in of the twist similar to that provided rapidly by a steaming treatment.
Distribution of the Substituents in Heterogeneously Methylated Celluloses
Authors: Abe Toru , Matsuzaki Kei , Hatano Akira , Sobue Hiroshi
Published: March 2008

Four methyl celluloses made from cotton linters with dimethyl sulfate and alkali in toluene and one commercial product were hydrolyzed. Unsubstituted, monomethyl, di methyl, and trimethyl glucose in the hydrolyzates were separated by filter paper chro matopile, and the results were compared with the calculated values of Spurlin and the experimental values of other investigators.
The Strength and Weakness of Cotton Fibers
Authors: Wakeham Helmut , Spicer Nancy
Published: March 2008

Previous work has shown that the structural reversals of cotton fibers are points of weakness at which the fibers prefer to break. The present paper is concerned with the distribution of these reversals in the individual fibers and with differences in reversal frequencies for various cotton varieties. It is shown that indivual fibers vary greatly in their tendency to break at reversals. Fiber reversals are much more frequent at the tip end of the fiber than at the base end. In general, cotton varieties which have high reversal frequencies are weaker cottons as determined by single-fiber and bundle strength tests. The implications of these findings to mechanical properties of the fibers and to their behavior in yarns are discussed.
Cotton Quality and Fiber Properties
Authors: Virgin W.P. , Wakeham Helmut
Published: March 2008

The purpose of this research was to evaluate the use of single-fiber testing methods for the determination of cotton fiber properties and for the prediction of yarn quality. Samples of unprocessed cotton, finisher drawing sliver, and 36's carded yarn were ob tained for 21 domestic cotton varieties representing extremes in length, fineness, and strength. Single fibers from all three processing stations were tested for their fineness and mechanical properties: crimp, Hookean slope, breaking load, elongation, elastic modulus, breaking stress, and energy to rupture. Ranges for each of these properties were established. The results were compared with the mechanical properties of the fiber bundles, slivers, and yarns.

Correlation studies of the results show that all of the mechanical properties measured on fibers are related to fiber fineness and, among the varieties, to fiber length. Bundle strengths and elongations at clamp spacings greater than 1.5 mm. relate well to fiber breaking strengths and elongations. Sliver force-extension slope is dependent on fiber fineness and fiber elastic modulus. Yarn strength depends strongly on fiber length, fine ness, and elastic modulus, and only weakly on fiber strength; yarn elongation depends greatly on fiber elongation and elastic modulus.

These observations suggest that yarn strength and elongation are related to the single fiber properties and can be predicted from them fully as well as from bulk measurements of fineness and bundle strength data. They also indicate that elastic modulus is an im portant parameter for predicting fiber assembly behavior.
Dimensional Changes and Related Phenomena in Wool Fibers under Stress
Authors: Banky E.C. , Slen S.B.
Published: March 2008

The type and magnitude of dimensional changes occurring in wool fibers under stress were investigated by means of transverse and longitudinal measurements. The over-all rate of decrease in the fiber diameter as related to the rate of extension indicated a con stant volume distortion beyond the Hookean extension. However, slight deviations at approximately 5 and 27% extensions suggested the possibility of drastic structural changes at these levels. Data on the length contraction owing to crimp and observa tions at microscopic level regarding the absence of mechanical damages to the structural elements of wool under stress also are presented.
Performance Characteristics of Synthetic Fibers, Wool, Viscose, and Blended Fibers in Axminster Carpets
Authors: Schappel J.W.
Published: March 2008

The soiling and crushing characteristics of nylon, Dacron,2 Orlon,3 Saran, Dynel, acetate, wool, and smooth viscose, as well as the 50/50 blends of the synthetics and wool with smooth viscose were studied in Axminster carpets.

Soiling properties are shown to be related to the fiber surface smoothness and avail able surface area, and the reflective properties of the fiber. The soiling properties of fibers in blends are not influenced by the companion fibers of the blends. Electrostatic effects are unrelated to the soiling properties of carpet fibers.

Smooth viscose has the highest soil resistance of all the fibers appraised and con tributes this property to carpets consisting of blends of smooth viscose and synthetics.

Crush recovery characteristics of the synthetics are good with nylon and Orlon per forming better than wool. Blends of the synthetics and smooth viscose show poorer crush recovery than the average crush properties of the respective fibers.

Pile density is a variable controlling crush properties of carpets and varies in rela tion to the fiber's specific gravity. Differences in pile density of carpets as a result of differences in specific gravities of fibers are insufficient to materially shift the crush re sistant rankings of the fibers.
The Effect of Laundering, Mercerizing, and Simulated Vat Dyeing on the Properties of Partially Cyanoethylated Cotton
Authors: Reinhardt Robert M. , Markezich Anthony R. , Moore Harry B. , Reid J. David
Published: March 2008

The effect of laundering, mercerizing, and simulated vat dyeing on the properties of partially cyanoethylated cotton was investigated. Cotton sheeting cyanoethylated to various nitrogen contents, from 2.2 to 6.4%, was subjected to laundering, mercerizing, or simulated vat dyeing. The samples were then analyzed for thread count, weight, and thickness and tested for breaking strength, elongation, tearing strength, abrasion resistance, air permeability, stiffness, moisture regain, heat resistance, and rot resistance. In addition, wrinkle recovery of the partially cyanoethylated and untreated cloth was determined.

Results of the study indicate that neither laundering, mercerizing, nor simulated vat dyeing seriously affects the usual textile properties of partially cyanoethylated cotton. The rot resistance and heat resistance of samples of more than 4% nitrogen content were not greatly impaired by these treatments; however, a sample of 3.2% N was not rot- resistant after these subsequent treatments.
Definition and Measurement of Crimp of Textile Fibers
Authors: Alexander Ernst , Lewin Menachem , Muhsam Helmut V. , Shiloh Miriam
Published: March 2008

Two fundamental concepts are defined, the effective crimp diameter and the effective wave number. The corresponding figures for these concepts are calculated from the measurements of the width values of the plane projection of a rotating fiber and from the measurements of the crimp ratio. These figures are obtained for a fiber under a certain load, and take into account the spatial nature and the statistical aspect of crimp. An effective curvature is determined as well. Results are obtained for 90's Merino and 52's Scotch-Blackface wool fibers. It is shown that the higher quality wool fibers are associated with lower effective crimp diameters and higher effective wave numbers.
Spindle Drafting of Woolen Slubbings
Authors: Angus J. , Martindale J.G.
Published: March 2008

An apparatus incorporating a single mule spindle was designed to draft woolen slub bings under a variety of conditions of twist and speed, and to measure the drafting forces generated. Experiments were done on this apparatus and on the mule itself.

The way in which drafting force is generated was investigated for Cheviot and Saxony slubbings with varying speed, count, and twist. The way in which the thread irregularity changed during drafting was investigated simultaneously. It was found that force first increased with extension and then decreased. During this second stage of decreasing force, evidence was sometimes found of the spasmodic slipping and sticking of fibers. Levelness of thread improved while drafting force was increasing, but deteri orated rapidly as the force declined. This indicates that optimum draft might be deter mined by force measurements. The angle of inclination of the spindle was also found to affect the magnitude of the drafting force.

A two-phase hypothesis of fiber behavior has been advanced, in which it is suggested that fiber response during the first phase consists mainly of straightening and stretching. This is superseded by a second phase which is characterized by fiber slippage, often of a violent nature.

It is suggested not only that this does provide a new standpoint from which the process of spindle drafting can be considered, but also that development of the experi mental technique might provide ready means of investigating the importance of various fiber properties, and their modification, in the spinning process.
Improved Instrument to Measure the Moisture Content of Lint Cotton, Seed Cotton, and Cottonseed
Authors: Reddick J.A. , Mayne S.C. , Berkley Earl E.
Published: March 2008

The cotton and cottonseed industries are modernizing technical methods and instru ments along with suppliers of other raw materials. Described herein is an improved electrical conductivity instrument for measuring rapidly and accurately the moisture content of lint cotton, seed cotton, and cottonseed. Moisture contents in percentages, based on total weights of samples, are indicated on a direct reading dial. Accurate measurements of ± 1% in the 3.3-22% moisture range are obtainable with this instru ment when compared with standard oven metheds. A relatively large representative sample (35 g. lint cotton, 100 g. seed cotton and cottonseed), control of sample density (600 lb./sq. in. pressure), and a stable electrical system are the contributing factors for a successful instrument.
Density Changes in Cellulose Treated With Urea-Formaldehyde Resins
Authors: Steele Richard , Schiwall Raymond P.
Published: March 2008

Density changes produced in cotton and rayon fabrics by treatment with four thermo setting resin precondensates have been determined in density gradient columns. With the assumption that the density of resin cured in vitro corresponds to its density in the fiber, the results indicate that the predominant effect is fiber swelling, with very little resin being deposited in void spaces not previously accessible to the solvent mixture in the gradient column. Scouring the treated fabric to remove reaction residues lowers the density, indicating that the fiber structure does not collapse, presumably because it is stabilized by the reacted resin.

The effect of resin concentration on moisture regain was also determined with these samples. The results are consistent with the changes in mechanical properties observed for cross-linking and non-cross-linking resins on cotton and rayon.
Effects of Cross-Linkage in Wrinkle-Resistant Cotton Fabrics
Authors: Frick J.G. , Andrews B.A. Kottes , Reid J. David
Published: March 2008

The cross-linking of cellulose in cotton fabric with three wrinkle-resistance finishing agents has been investigated. The three agents used were dimethylol urea, dimethylol ethyleneurea, and formaldehyde. With all three compounds, maximum crease recovery angles are obtained with a substitution of 0.04-0.05 cross links per anhydroglucose unit. As crease recovery angles increase, the elongation and permanent set caused by an 8-kg. tensile load on a 1-in. fabric strip decreases. Permanent set approaches zero near 135° warp crease recovery. Changes in the load-elongation curves indicate elastic modulus increases as crease recovery angles increase. Treatment of fabric to the same crease recovery angles with the three compounds reduces tearing and breaking strengths to different extents. The differences are due to different amounts of cellulose degradation caused by the aciclic catalyst systems and not to the structure of the cross links.
Isocyanate Modification of Wool in Dimethyl Sulfoxide
Authors: Koenig N.H.
Published: March 2008

In the presence of hot dimethyl sulfoxide, a variety of monoisocyanates penetrate into and react chemically with wool. Dimethyl sulfoxide is superior to pyridine, the only other known reaction medium, in respect to cost, odor, and toxicity. Reaction is very rapid when the ratio of materials is 3 ml. of dimethyl sulfoxide, 2 ml. of phenyl isocyanate, and 1.2 g. of dry wool fabric; uptake of isocyanate is about 36% of the weight of the wool in only 10 min. at 105° C. Isocyanate-treated fabrics are more resistant to chemicals and to laundering shrinkage.
Some Torsional Properties of Wool Fibers
Authors: Nordon P.
Published: March 2008

The variation of torsional rigidity of wool fibers with relative humidity is investi gated by dynamic methods at frequencies ranging from 115 to 0.00028 cycles/sec. Measurements are reported of the equilibrium values at various humidities and of the kinetics of change of rigidity as the humidity is altered. It was found that any change in the relative humidity surrounding the fiber first led to a reduction and then to a partial recovery of the rigidity. Equilibrium values of the rigidity varied about 3.5 to 1 over the frequency range used, the effect being most pronounced at the higher humidities. A qualitative discussion of the data is given.
Fatigue in Textile Fibers
Authors: Lyons W. James
Published: March 2008

A single-station machine on which a fiber can be fatigued in a localized region, by being axially rotated in a bent configuration, has been built. The test fiber, on either side of the bend, is mounted on shafts at 90° to each other, driven at the same rotary speed. Speeds up to 550 rpm are attainable.

Nylon 66 and nylon 6 monofils in a number of diameters from 8 to 28 mils have been fatigued in biaxial rotation on this machine, in a fourfold range of rotary velocities and for periods of 15, 30, and 45 min. They were then tested for residual breaking tenacity and extension. A few fibers have been fatigued for other periods of time, or to rupture, for microscopic examination of the fatigued region.

In most samples the rupture properties decrease with increasing rotary velocity, for any given fatiguing period. The rate of this decrease tends to be lower in the range of higher velocities. The shapes of the breaking-extension curves are largely determined by those of the breaking-tenacity curves, reflecting the near-linearity of the tenacity- extension relationship. The monofils of smaller diameter, especially those of nylon 6, are less affected by the increase in rotary velocity. In most of the samples, the residual breaking tenacity appears to be largely determined by the total number of revolutions sustained by the specimen, with no consistent influence of rotary velocity on the results.

Monofils of the higher draw ratios and those that had been heat-set show a much sharper decline in residual properties with increasing rotary velocity than do the non- heat-set samples of lower draw ratio. However, the breaking tenacities of the heat-set samples retain their relatively higher positions after fatiguing under most conditions.

Representative photomicrographs of monofils fatigued at various velocities and for different periods short of rupture show progressive development of diagonal fissures in the fatigued regions, especially in the nylon 66, and of a bulbous expansion in the nylon 6 specimens. Photomicrographs of the broken ends of monofils fatigued to rupture indi cate that the breakage in nylon 6 occurs across planes coinciding with the diagonal fissures. In nylon 66 the breakage appears to occur in a roughly transverse plane.
Mechanics of Elastic Performance of Textile Materials
Authors: Freeston W. Denney , Platt Milton M. , Schoppee Meredith M.
Published: March 2008

A theoretical analysis of the load-elongation behavior of idealized plain-weave fabrics subjected to biaxial stresses is presented. Fabric strains resulting from both crimp interchange and yarn extension are considered. The analytical expressions de rived have been solved with the aid of a digital computer for both linearly elastic and elasto-plastic materials. Time effects, although not explicitly included, are discussed.

Generalized plots of the results are presented for the two extremes of initial fabric structure: (1) equal crimp distribution in both sets of yarns and (2) one set of yarns noncrimped (straight). The predicted and measured response of model fabrics are compared.
Reaction of Aryl Isocyanates With Cotton Cellulose
Authors: Hobart Stanley R. , McGregor Howard H. , Mack Charles H.
Published: March 2008

Eleven N-arylcarbamylated celluloses were prepared by a pad-cure treatment of cotton with phenyl N-arylcarbamates as isocyanate generators. Add-ons up to 8.5% were obtained by impregnating the fabric with a dimethylformamide (DMF) solution of the phenyl carbamate and curing at 180-200°C for 4-5 min. The extent and efficiencies of these cotton cellulose reactions were observed by means of add-ons, nitrogen contents, and change in pickup of acid dyes. The activating aryl substituents were dialkylamino, methoxyl, methylthio, and methyl electron-donating (+E) groups. N-pyridylcarbamates were also used. The modified cotton fabrics exhibited improved rot resistance and those containing amine groups had ion-exchange properties.
Stress-Strain and Recovery Properties of Cross-Linked Rayon Yarns in the Wet and Dry States
Authors: Rebenfeld Ludwig , Oster Clinton V. , Klurfeld Laurence F.
Published: March 2008

Continuous-filament rayon yarns were subjected to an acid-catalyzed cross-linking treatment using dihydroxydi methylol ethyleneurea under pad-dry-cure conditions to two levels of add-on. The stress-strain curves of these yarns were measured at a constant 40%/min rate of extension in the dry (65% RH and 70°F) and wet states and in an "anhy drous" condition. In the dry state, cross-linking increases the elastic modulus, the stress at the yield point, and the stress at break, and decreases the extension at break and the energy to break. In the wet state, there is a disappearance of the primary yield point and the deformation process is plastic-like from the onset without an initial Hookean elastic region. Furthermore, in the wet state, the untreated yarns are weaker and more extensible than under dry conditions, but cross- linking again increases strength and decreases extensibility. Cross-linking brings about the reappearance of the primary yield point even in the wet state. This is interpreted to reflect a protective effect of the hydrogen-bond network in the cellulose structure.

The recovery properties were measured as a function of load, strain, and energy of deformation over the entire possible range of values. In uncross-linked state, dry yarns are more resilient than wet yarns, when measured from given loads of deformation, whereas wet yarns are more resilient than dry yarns, when measured from given strains, except for strains below the primary yield point. At low energies of deformation, uncross-linked dry yarns are more resilient, whereas at higher energies of deformation the reverse is the case. These data clearly indicate that, in comparing the recovery prop erties of yarns with different stress-strain curves, an entirely different view of this important yarn characteristic is obtained, depending on whether recovery is measured from given loads, strains, or energies of deformation. Cross-linking significantly increases resilience both in the wet and dry states, particularly from higher levels of deformation.
Rapid Bleaching of Wool With Extremely Intense Visible Light
Authors: Launer Herbert F.
Published: March 2008

Unbleached 7-oz wool flannel was bleached in seconds by visible light of very high intensity, near 5 watts cm2, by close proximity to a 1000-watt, water-cooled mercury vapor lamp incorporating a glass filter in a novel arrangement. Bleaching was quite uniform throughout the thickness of the fabric. Results with three spectral distributions, which affect the hue of bleaching by spectral conformity, are compared with the results of peroxide bleaching. Stabilities are also compared. Practical application and the advantages over present methods of this dry, pollution-free procedure are discussed.
Pad-Bake Reactions
Authors: Cvculo J.A.
Published: March 2008

A new reaction of aqueous amic acid-cellulose has been found. It has led to a fast, simple, pad-bake process for modify ing cellulose. The structure of the modified reaction product is postulated to be a cellulose half-acid ester.

Some comments are made on the mechanism and generality of the reaction. Also mentioned is the possible value of the easily made cellulose half-acid ester derivative as a precursor for subsequent reactions to obtain cellulosic fabrics with improved properties. Specific examples noted are cellulose hemisuccinate, phthatate, maleate, and glutarate.
Intramolecular Hydrogen Bonding in Dimethyl Sulfoxide Solutions of Glucose and Polyglucoses
Authors: Ghosh K.K. , Gilbert R.D.
Published: March 2008

The downfield position (about 5r or lower) of certain hydroxyl proton resonance signals in the pmr spectra of glucose and polyglucoses in dimethyl sulfoxide solutions suggest the presence of intramolecular hydrogen bonds, namely, one involving the C-4 and C-6 group OH in glucose and, additionally in the polyglucoses, one between the C-3' OH and the ring oxygen in the adjacent glucopyranoside ring. The OH signals in the 5r region are in the proper ratio for the C-3' and C-4 OH protons in the polyglucoses examined. Absorption bands at 3500-3550 cm''in the ir spectra of methyl α-D- gtucopyranoside, cellobiose, and methyl cellobioside dissolved in DMSO and the absence of such an absorption in the methyl 6-deoxy-α-D-glucopyranoside spectrum provide further confirmation.
Recovery from Tensile Strain in Knitted Cotton Fabric after Cross-Linking
Authors: Andrews B.A. Kottks , McSherry Wilbur F. , Frick J.G. , Cooper A.B.
Published: March 2008

Extension under tensile load and recovery from extension was studied on a jersey knit cotton fabric after cross-linking treatments. The cross-linking reduces breaking strength and elongation-at-break, with only small changes in the load- elongation curve up to the break point. Set resulting from a high load is reduced by an amount approximating the reduction in extension; actual recovery is increased only slightly. Length increase from reheated loading can be reduced by cross-linking, but the extent of reduction is also influenced by noncross-linking additives.
The Stabilization of Irreversibly Deformed Keratin Fibers
Authors: Weigmann H.-D. , Dansizer C.J.
Published: March 2008

The significance and relative contribution of the various factors that contribute to the stabilization of the extended state of the keratin fibers have been investigated. In this context, the stress relaxation of extended keratin fibers in 7.2 M LiBr solutions, as well as their recovery and recrystallization behavior, were studied. A kinetic analysis of stress relaxation in 7.2 M LiBr at a strain of 60% indicated that the controlling mechanism is an SH-catalyzed disulfide inter change with an activation energy of 22.9 kcal/mole. The recrystallization in a stable β-configuration of the chemically molten and extended keratin fibers is only possible after a structural rearrangement which removes disulfide bonds from stressed positions. If this rearrangement is prevented, the β-crystallites remain unstable even after an extended re crystallization time. Stabilization of the extended state by the formation of stable covalent cross links is not possible, unless crystallization of β-crystallites is permitted. The formation of β-crystallites alone, on the other hand, is also not sufficient to stabilize the extended state, unless the β-configuration is supported by stable covalent cross links. After a melting-extension-recrystallization cycle at 96°C, the total longitudinal deformation of the keratin fibers approaches 125%, which would correspond to the theoretical α-β-translation distance.
A Study of Flammability of Cotton, Polyester, and their Blends
Authors: Dipietro J. , Stepniczka H. , Nametz R.C.
Published: March 2008

This study was undertaken to measure quantitatively the effect of temperature on the oxygen index values of several fabric samples of cotton, polyester, and their blends. The smoke density generated during the burning of these fabric samples at their oxygen indices was also studied at various temperature conditions. The results indicate a definite rela tionship of burning behavior with temperature, fabric weight, and composition of the blends. Two commercially avail able flame-retardant finishes were employed in this comparative flammability study of treated and untreated specimens. A novel instrument, which complies with standard laboratory procedures, was employed throughout this study, and it was found to be versatile, convenient, and highly reproducible in the generation of the data.
N,N-Diethylaziridinium Chloride as a Coreactant Catalyst for Reactions of N-Methylol Reagents with Cellulose
Authors: Roberts E.J. , Wade C.P. , Rowland S.P.
Published: March 2008

The use of N,N-diethylaziridinium chloride (DAC) as a coreactant catalyst for the reaction of cellulose with several N-methylol compounds has been investigated. This catalyst was effective in promoting reaction between cotton and all of the four methylol derivatives tested but especially effective in promoting the reactions of dimethylolethyleneurea and methylated trimethylolmelamine with cotton cellulose. These two cross-linking agents could be used in a delayed- cure process with DAC as the catalyst. Little reaction occurred with either of these reagents during delay periods up to 33 days and no increases in recovery angles were found in the delayed and uncured samples. The delayed-but-cured samples showed crease-recovery angles equal to those achieved in immediate cures.
Tensile Characteristics of Twisted Continuous-Filament Glass Yarns
Authors: Jones J.E. , Haddad G.N. , Sutton J.E.
Published: March 2008

The results are reported of a comprehensive experimental investigation of the tensile behavior of twisted continuous- filament glass yarns. Existing theoretical treatments are reviewed and their compatability with the experimental results are examined. A physical model is proposed, based on a wrapped-ribbon twist geometry, which predicts both tensile modulus and tenacity of glass yarns as a function of the twist angle. The effect of filament bending strain on yarn tenacity has been included in the analysis. Excellent agreement between the model and the experimental results is shown.
Comparison of Sulfonoethylated Cotton and Diethylaminoethylated Cotton as Built-In Catalysts for Delay Cure Processes
Authors: Perrier Dorothy M. , Benerito Ruth R. , Soignet Donald M.
Published: March 2008

A two-stage or delayed-cure process for the durable-press finishing of cotton which depends on the significantly different reactivities of cellulose with methylol functional groups at low and high temperatures in the presence of an acid catalyst has been studied. Dimethylolethyleneurea (DMEU) and a less reactive reagent, dimethyloldihydroxyethyleneurea (DMDHEU) were selected. Selection of built-in acid sites within the cellulose matrix was based on use of a group whose acid function was activated by an increase in temperature and of a group whose acid function was less dependent on temperature. Diethylaminoethyl (DEAE) cotton in the hydrochloride form satisfied the former requirement and the acid form of sulfonoethylated (SE) cotton the latter. Effects of time of storage on fabric properties imparted to DEAE-cotton and to SE-cotton by pure DMEU and pure DMDHEU by a delayed-cure process have been compared. Data are given to indicate when the commercial grade DMEU or DMDHEU can be substituted for the pure reagent in these processes.
The Heat of Wetting of Annealed Wool
Authors: Haly A.R. , Snaith J.W.
Published: March 2008

An adiabatic calorimeter was used to measure the heat of wetting of annealed and unannealed wool. Prior to wetting, the samples were adjusted to various water contents. From the curve relating heat of wetting and water content, differ ential beats of wetting were computed. It is concluded that annealing treatments cause changes no greater than 1 cal/g in the heat of wetting, and that the calculated results for differential heat as a function of water content are in fair agree ment with values that have been derived from a synthesis of previous work.
The Concept and Measurement of Extinguishability as a Flammability Criterion
Authors: Miller B. , Goswami B.C. , Turner R.
Published: March 2008

Burning experiments in enclosed spaces have shown that oxygen depletion leading to flame extinction occurs even in a relatively large volume of air, because convection is only partially effective in supplying air to a burning flame and removing products of combustion and pyrolysis. Quantitative evaluation of extinguishability through oxygen depletion determined under realistic burning conditions would, therefore, be a valuable indication of the hazard potential of a material. Accordingly, a method has been developed for establishing a characteristiol minimum-burning condition in terms of oxygen concentration which results in a more stringent criterion for the innate flammability of a material than the conventional oxygen index (O.I.) value. The TRI Flammability Analyzer is used to measure steady-state flame propagation rates at several oxygen concentrations high enough to support steady burning. Extrapolating the resultant linear burning rate oxygen concentration relation to zero burning rate-yields an intrinsie (O.I.)0. With the analyzer. it is possible to determine intrinsic indices for the more common and vigorous upward directions of burning, and the upward indices obtained for a group of natural and synthetic fabrics, woven and knitted, are apprediably lower than the indices for the downward direcion. Indeed, all fabrics studied. except Nomex®. are found to be inherently capable of upward burning in air.
Gas-Liquid Chromatography of Trimethylsilyl Derivatives of Cellulose Crosslinking Agents
Authors: Divatia A.S. , Shroff J.J. , Srivastava H.C.
Published: March 2008

A technique is described for isolation of some cellulose crosslinking agents and gas-liquid chromatography of their trimethylsilyl derivatives.
The Effect of Crystallinity on the Vapor-Phase Sorption of Acetone in Oriented Poly(ethylene terephthalate)
Authors: Sirur P.V. , Cates D.M. , Guion T.H. , Walsh W.K.
Published: March 2008

Sorption measurements of acetone vapor (activity = 0.9 at 50°C) on oriented PET fibers indicated that sorption capacity does not decrease linearly with increasing crystallinity. It was found that the acetone uptake based on amor phous volume, when plotted vs crystallinity, passed through a minimum at 0.48 volume fraction crystallinity.