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A paper chromatographic study of the amino acid compositions of several histo logical fractions of wool has been conducted. The fractions considered were epicuticle, cortical cell membranes, paracortex, and regenerated oxidized keratin. Samples of these fractions were hydrolyzed with hydrochloric acid, and quantitative analyses of the amino acid content of these hydrolysates were accomplished through a modification of the standard two-dimensional paper chromatographic technique. The epicuticle was found to contain normal amounts of cystine but extraordinarily large quantities of aspartic acid and glutamic acid. In addition to confirming the results of the phosphotungstic acid analyses for cystine reported in a previous paper [14], the chromatographic studies of the paracortex showed large amounts of the basic and small amounts of the dicar boxylic amino acids to be present. The extremely low total of amino acid content found in the cortical cell membranes indicated the possible presence of some nonprotein constituent.

The manipulation of the physical characteristics of nonwovens and paper by variation of fiber and web geometry is briefly reviewed in terms of a new system of bonding in which the adhesive interfiber forces are a consequence of ionic chemical bonds. These bonds were created by the sequential covalent introduction of anionic sites onto the interior and exterior surfaces of microporous pulp and rayon fibers using a chloro-s-triazinyl fiber reactive dye and subsequent stoichiometric reaction with crosslinking polycations derived from ethylenimine. The tensile properties of both the pulp and rayon fiber assemblages were significantly augmented as a result of the development of both ionic inter- and intra-fiber bonds.

Decomposition of cellulosic fibers by thirteen strains including three species of the obligately anaerobic genus Ruminococcus has been investigated with regard to the effects of the chemical composition and physical state of the fiber. Of the thirteen strains only six were actively cellulolytic. In test systems containing 50 mg of fiber in 10 ml of medium, nearly complete solubilization of substrate was observed in 11 to 14 days. The substrates were jute, cotton, alfalfa, filter paper, and varous materials derived from these. As with other cellulolytic systems, crystalline celluloses and coarse particles were resistant to attack. Gravimetric assays indicated that lignification reduced digestibility more than could be predicted from the lignin content alone, suggesting that in part the resistance of lignified fibers results from masking of the cellulose. The protective effect of lignification in jute is further supported by the fact that alfalfa stems having the same lignin content as jute were about five times as digestible as jute. Acid treatment enhanced the resistance of both jute and cotton to degradation. Alkali treatment decreased resistance to degradation of both jute and cotton, the effect on jute being particularly pronounced. Pure α-celluloses were rapidly degraded regardless of their origin. Stimulation of cellulose degradation by the hemicellulose present in the holocellulose was negligible.

The action of trypsin on oxidized normal and copper-deficient wool has been ex amined by ( i ) N -terminal-residue estimations and (ii) paper electrophoresis and chromatography on the tryptic digests. Trypsin readily solubilizes oxidized wool but does not digest it completely, probably because of its high cysteic-acid concentration. Little difference was found between normal and copper-deficient wool, although the latter gave a smaller amount of a certain group of acidic peptides. Preliminary tests on the chromatography of the tryptic digests using ion-exchange resins are reported.

The amino-acid compositions of oxidized normal and copper-deficient wool from one sheep and of two components separated from them at pH 6 have been measured by ion exchange chromatography. The differences between the "soluble" and "insoluble" components are those expected from previous work. The "insoluble" components from normal and copper-deficient wool appear to be identical, although there is a small dif ference in the "soluble" components. Attempts at fractionating the "soluble" components , by chroniatogrtphy, paper electrophoresis, and dialysis gave indications of heterogeneity but were not very successful.

This paper reviews the literature on the microbiological deterioration of woolen textiles; it lists wool-destroying micro-organisms, describes the factors governing their growth and activity on wool, and discusses the mode of attack by micro-organisms on wool. Also, the methods developed for prevention of deterioration of woolen textiles by micro-organisms are described.

A study was made of the changes in degree of polymerization (DP), water retention value (WRV), and yield when high α-sulfite pulp (α-SP) is beaten or swollen with zinc chloride or sodium hydroxide and treated with cellulase. For a sample swollen with sodium hydroxide, the decrease in DP is large, and the DP decreases easily to a value which corresponds approximately to the level of DP in acid hydrolysis. On the other hand, a sample treated with zinc chloride solution shows a small decrease, while a beaten sample indicates an intermediate DP value. It is assumed from these results that sodium hydroxide swells the amorphous region of the fiber greatly but has little effect on the crystalline region, whereas zinc chloride swells the crystalline region but its swelling effect on the amorphous region is not very great. Cellulase can be utilized for analyzing the structure of cellulose fiber.

A paper chromatographic method for determining the extent of damage by oxidizing or alkaline solutions to wool fabrics of unknown history is described. The presence of other textile fibers does not constitute an interference.

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.

The biodegradability of several packaging films was determined; the degradation of the polymeric films, polypropylene and poly(vinyl chloride), was compared to a coated paper and several coated cellophanes. The films were buried in bacterially-active soil and the extent of bacterial degradation was determined by measuring the reduction in tensile strength as a function of burial time. The results show that the polymeric films do not degrade after five weeks of soil burial while the glassine and cellophanes do degrade. Surprisingly, the cellophane films decompose at a faster rate than the coated glassine sheet.

A new method involving trials on 40 grain and 50 grain samples has been proposed for the determination of fiber maturity using the Micronaire. Tests on 130 samples have revealed that this method is significantly correlated with fiber maturity determined by the standard caustic soda swelling technique and is as efficient as the spacer technique. Further, the theoretical basis for extending the use of Micronaire for determination of cotton fiber maturity is also discussed.

Previous work [9] on the degradation of cotton during mechanical processing has been extended to include a study of the action of the pickers under various operating conditions. The results indicate that blade and carding beater types cause different amounts of degradation, that the amount of degradation caused by a very close setting can be differentiated from that due to wider spacings, and that the speed of rotation of the beater has a degradation effect which is detectable only after several passes—i.e., several consecutive picker operations. The effect of consecutive picker operations under similar conditions of the other variables is readily discernible.

Radiant energy from “Germicidal” lamps, consisting of 89% of ultraviolet at 253.7 mμ, caused undyed wool fabrics to become strongly greenish-yellow in air of normal moisture content. Comparative reflectance and absorption measurements indicate that the color is due to the production by this ultraviolet of probably two or more substances that absorb in the violet-blue and in the orange regions. The violet-blue absorber, which accounts for the yellowness, increased with time and temperature of irradiation. The orange (together with the violet-blue) absorber accounts for the greenness; it varied with time and temperature and reached a maximum in 45 min (direct contact with lamp). Greening was not evident under 2.5 min or over 10 hr. Both absorbers were produced in dark reactions that follow the initial photochemical reactions, as shown by the effect of temperature, which was greater for the orange absorber. The rate of formation of both absorbers, but especially the orange, was decreased by even moderately impeding the flow of air to the wool during irradiation. Ozone was not involved. Tristimulus and Munsell color values are given for comparison in one case. The effects of ultraviolet were practically indistinguishable for 6.1-oz flannel purified with solvents and for tropical worsted and 4.7-oz flannel of normal grease and oil content.

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.

Comparative exposures of mercerized and unmercerized cotton to light and to weath ering brought out anomalous effects in the breakdown of cotton cellulose. There was less deterioration of the mercerized cotton, as measured by the ability of the fabric to resist rupture by tension (measured by breaking strength), but at the same time, more degradation (as determined by fluidity measurements), indicating a reduction in average degree of polymerization of the cellulose. These observations are consistent with reports in the literature that mercerized cotton is somewhat more susceptible to oxidation and to hydrolysis than comparable un mercerized cotton. The behavior in exposure to light evidently is part of a general phenomenon, because higher fluidities have been ohserved for the chemically reactive mercerized cottons under conditions where the strength losses for mercerized and un mercerized cottons were equal. The higher retention of strength by the mercerized cotton may represent a significant advantage, because it promises a longer service life of mercerized goods when deteriora tion occurs mainly from exposure to sunlight. When ordinary unmercerized cotton has lost half strength, corresponding mercerized cotton can be expected to last for 14 to 13 longer before reaching that level.

Cotton has been made unusually resistant to degradation by weather by first dyeing it with certain light-stable vat dyes and following this with partial acetylation. Vat dyeing alone or partial acetylation alone do not make cotton significantly more resistant to deterioration by sunlight than undyed fabrics, except for a few colors which do have a protective effect. However, when these two processes are combined, excellent re sistance to solar radiation is added to the excellent mildew- and rot-resistance of partially acetylated cotton. Data were obtained on a number of individual vat-dyed and vat-dyed and acetylated cotton materials that had been exposed to outdoor weathering. From the results of these tests, it is estimated that the combination of vat dyeing with light fast colors and acetylating may more than double the outdoor service life compared to cotton vat dyed only, or acetylated only, with somewhat better color retention when the cotton has been both dyed and acetylated.

A quantitative laboratory method for evaluating levelness of acid wool dyes is described. The procedure consists of running half of a normal yarn-dye cycle and then making additions of white yarn and dye liquor equal in amount to those in the original batch. The second half of the cycle is then run, and the yarns are removed. Reflectances of the two dyed yarns are determined on a G. E. recording spectrophotometer and a "levelness index" is calculated as the ratio of dye concentration on the yarn added at the mid-point of the cycle to that on the yarn started at the beginning of the cycle. The technical background of the test method is outlined and the results of tests on repre sentative dyes are tabulated. It is shown that the test method has sufficient flexibility to permit examinations of the effects of dyeing variables on levelness. An example is cited showing the effect of salt concentration on levelness of Alizarine Cyanine Green CG ex. (C. I. 1078). The example above is applied to plant production, and the levelness of 500-pound Hussong stock-dyed batches is evaluated by spectrophotometer reflectances, converted to dye concen tration, of stratified samples from the batches of stock. It is shown that the coefficient of dye concentration variation among the 8 samples from a plant batch is proportional to the laboratory "levelness index."

The study analyzes the causes for lea count variation on the basis of experiments in the pilot mill, detailed investiga tions at mill level, and theoretical considerations. The extent of influence of various sources of count variation is studied. A relationship between count C.V. and strength C. V. is derived.

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.

Ice cold water was employed on both laboratory and pilot plant scales to extract re sidual monoethylamine reagent from decrystallized cotton materials. The use of cold water retained the high degree of decrystallization achieved and further retained the cellulose I crystal lattice of native cotton in the remaining crystalline regions. Advan tages of this cold water extraction process compared with use of organic solvents are enumerated.

Two artificial soils were most effectively removed from wool in an impeller-type machine, but, considering their greatly different effects on felting rate, the differences in efficiency of all the machines studied were relatively small. A rotating-drum machine was almost as good as the impeller-type for removing a particulate soil, but was worst of all for an oily soil. Soap removed the oily soil from both untreated and shrink-resist-treated wool more effectively than did the synthetic anionic detergents, but the order was reversed for the particulate soil.

Samples of vinylated cotton slivers with DS (degree of substitution) values of about 0.05 and below were found to be soluble in cupriethylenediamine hydroxide solution. Vis cosity determinations indicated D.P.'s of 97 to 586 which were considerably lower than that of the starting cotton (about 3000). Samples with higher D.S. values were all insoluhle in the reagent indicating at least a small amount of cross-linking. X-ray diffraction patterns made from the vinylated cotton slivers and cloth showed a nearly complete loss of cellulose crystallinity at D.S. values above about 0.10. This indicates good penetration of the crystalline regions by the catalyst and acetylene in the vinylation reaction. Good crease recovery angles were obtained by heating a sample of vinylated cotton print cloth ( D.S. = 0.21 ) with acidic catalysts. Most samples had breaking strength measurements 55-85% of the control cloth and showed 20-50% elongation at break.

Adhesion between sodium montmorillonite and cellulose was investigated by three techniques. (1) Beaten cellulose pulp was treated with aqueous clay suspensions to cover the fibers completely with a thin clay film. The adhesion was estimated by measuring the mechanical properties of handsheets made from this pulp. (2) Finely dispersed cellulose was added to montmorillonite suspensions in amounts up to 77 volume %. The mixed suspensions were cast into thin layers and dried to films. The clay-cellulose adhesion was estimated from the mechanical properties of these mixed films. (3) Cellophane strips were embedded in clay matrices, while other cellophane strips were bonded together. The stresses required to detach cellophane strips from the clay and the stresses required to rupture bonds between pairs of cellophane strips are measurements of the adhesion between clay and cellulose and of the autohesion of cellulose, respectively, and permit a direct comparison of the two, Results obtained with the first two methods indicate that the cellulose-clay adhesion is at least as great as the autohesion of cellulose. According to the third method, it is greater.

A critical study was made of the sulfuric acid carbonizing process. Three main fac tors governed the strength loss of the wool: (1) the acid content of the wool as it en tered the dryer; (2) the moisture content of the acid-containing wool as it entered the dryer; and (3) the temperature of the air used in drying the extracted, acid-containing wool prior to baking. Increase in any one of these factors beyond a certain level, while the others were maintained constant, caused a loss in tensile strength of the wool ; these three factors were all interrelated in their effects on the strength of the wool. Studies are presented which indicate the critical limits for each factor in raw wool carbonizing. Conditions were found which cumpletely charred the burrs in the wool without causing any measurable strength loss. The rates of absorption of acid by the wool and by the burrs were found to be very different. This was used to advantage in depositing the amount of acid on the burr contaminants required for satisfactory carbonization, while applying a minimum amount of acid in the wool. Wetting agents in the acid hath also had beneficial effects. Practical implications of the data for commercial processing are discussed.

Fiber fineness, as measured by the Micronaire, and prior treatments have been found to be important factors in determining the rate and extent of cyanoethylation of cotton. Fineness was found to be a good index of the rate of reaction for both raw and pressure- boiled cotton fibers. Prior treatment of yarn by ethanol extraction, pressure boiling with 2% caustic ethanolamine extraction, and mercerization—both slack and at constant length—affected the rate of cyanoethylation and the rot resistance of the product.

The degradative effects produced in cotton and other textile fibers by unfiltered light from a "Sunshine" type carbon arc lamp were compared with those which occurred in identical mate rials during natural weather exposure tests, in which sunlight is believed to be the chief degrading factor. These comparative tests were designed to afford needed information about the action of short-wave radiation on textiles, and to evaluate the practical utility of such radiation in accel erated weathering techniques.

In a series of trials in four carbonizing mills, the addition of a nonionic surface active agent to the sulfuric acid bowl resulted, in each experiment, in an increased yield of car bonized wool and, on spinning, increased yarn strength. In a similar trial with combing wool, the addition of nonionic surface active agent to the acid used for carbonizing re sulted in improved gilling and combing. The amount of acid taken up by the wool was increased by this addition, whereas the water content was decreased; this facilitated dry ing of the acidified wool.

The difficulty or ease of soil removal from soiled fabrics has been studied. Cotton, nylon, polyester, and wool fabrics were soiled with five oily soils and were laundered with eight different detergents under various washing conditions. Variable bath components were surfactant types, water hardnesses, detergent concentrations, and bath temperatures. The contribution of such fabrics, soil, detergents, and bath conditions were estimated by the analysis of variance. The contributions of these factors increase in the following order: (a) (Fabric) > (Fabric) X (Soil) > (Soil) > (Others) when water hardness is chosen as a variable; (b) (Fabric) > (Concentration) > (Fabric) X (Soil) > (Soil) > (Others) when detergent concentration is chosen as a variable; (c) (Fabric) > (Fabric) X (Soil) > (Others) when wash temp erature is chosen as a variable. For each condition, the detergent contribution of fabric is the largest, while that of mutual interaction between fabric and soil is also very large. , The analysis of variance suggested that the difficulty or ease of soil removal is determined mainly by the combination fabric and soil; the type of fabric or the mutual interaction between fabric and soil is also an important factor in deter mining the degree of soil removal. Surfactants are classified by pattern analysis, based on the detergent contribution of the various factors in detergent systems.

The formaldehyde treatment of wool fibers and fabric prior to bleaching by hot alkaline peroxide solutions has been investigated. Although pretreated fabrics exhibit lower alkali solubility and better handle after bleaching, characteristic degradation, shown by various single-fiber as well as fabric properties, is not retarded by the pre treatment. Formaldehyde pretreatment alone, under the conditions used, lowers the breaking stress and breaking extension of single fibers, but this degradation may not be severe enough to cause concern for many fabric uscs. Other experiments, without formaldehyde pretreatment, fail to support the claim that wool fibers possess increased susceptibility to damage when strained prior to bleaching.