Silk, Artificial

Leaving aside rayon and artificial silks generally, the first really effective polymeric textile fibre was nylon, discovered by the chemist Wallace Hume Carothers (1896-1937) in the Du Pont research laboratories in America in 1935, and first put into production in 1940, just in time to make parachutes for the wartime forces. This was the first of several major commodity polymer fibres and, together with high-density polyethylene introduced about the same time and Terylene , polyethylene tereph-thalate, introduced in 1941 (the American version is Dacron), transformed the place of polymers in the materials pantheon. 

The minerals on which the work was performed during the nineteenth century were indeed rare, and the materials isolated were of no interest outside the laboratory. By 1891, however, the Austrian chemist C. A. von Welsbach had perfected the thoria gas mantle to improve the low luminosity of the coal-gas flames then used for lighting. Woven cotton or artificial silk of the required shape was soaked in an aqueous solution of the nitrates of appropriate metals and the fibre then burned off and the nitrates converted to oxides. A mixture of 99% ThOz and 1% CeOz was used and has not since been bettered. CeOz catalyses the combustion of the gas and apparently, because of the poor thermal conductivity of the ThOz, particles of CeOz become hotter and so brighter than would otherwise be possible. The commercial success of the gas mantle was immense and produced a worldwide search for thorium. Its major ore is monazite, which rarely contains more than 12% ThOz but about 45% LnzOz. Not only did the search reveal that thorium, and hence the lanthanides, are more plentiful than had previously been thought, but the extraction of the thorium produced large amounts of lanthanides for which there was at first little use. 

A. As I have already said, Sparte III did not produce any armament material, except the powder department at Rottweil, where mostly artificial silk was made. 

Used in metal treating/cleaning operations, petroleum well activation, refining ore in the production of tin and tantalum, hydrolyzing of starch and proteins in production of various foods, in the production synthetic rubber, vinyl chloride and alkyl chlorides and in the manufacture of fertilizers, dyes and dyestuffs, artificial silk and pigments for paints. 

Bemberg An alternative name for the Cuprammonium process for making artificial silk, named after J. P. Bemberg who commercialized the process in the early 1900s in several countries. 

Chardonnet A process for making artificial silk by nitrating cellulose and injecting the nitrate solution into water, thereupon regenerating the cellulose ... 

J.W. Swan produced threads of cellulose nitrate in 1883 by forcing its solution through a spinning jet. This was called Swan Silk. Carbon filaments for early electric light bulbs were made from Swan Silk. Chardonnet manufactured artificial silk commercially in 1884 from cellulose nitrate. 

Natural fibers go back to prehistoric days. Probably one of the early applications was the conversion of a fiber (possibly wool or cellulose) into thread or rope strong enough to be used in a snare, net, or cage. Literature as far back as the 17th century notes that people attempted to make fibers out of something other than cotton, wool, or flax. The first man-made fiber, known as artificial silk, was made in the 19 th century, when wood pulp was treated with nitric acid. The result was known chemically as cellulose nitrate and (eventually) commercially as Rayon. The commercial name referred to the sheen that has the brilliance of the sun. ... 

Uses Determining fat content in milk solvent for alkaloids, fats, oils manufacturing isovaleric acid, isoamyl or amyl compounds, esters, mercury fulminate, artificial silk, smokeless powders, lacquers, pyroxylin photographic chemicals pharmaceutical products microscopy in organic synthesis. 

Uses. Manufacture of lacquers, artificial leather, photographic film, artificial glass, celluloid, artificial silk, and furniture polish... 

Uses. Solvent chemical synthesis manufacture of smokeless powders, artificial silk, and lacquers... 

An interesting series of values for the specific surfaces of various artificial silks was likewise obtained with the aid of methylene blue. The following data indicate the wide variations in specific surface. 

Throughout human history a limited number of fibers provided the fabric used for clothing and other materials—wool, leather, cotton, flax, and silk. As early as 1664, Robert Hooke speculated that production of artificial silk was possible, but it took another two hundred years before synthetic fibers were produced. The production of synthetic fibers took place in two stages. The first stage, started in the last decades of the nineteenth century, involved chemical formulations employing cellulose as a raw material. Because the cellulose used in these fibers came from cotton or wood, the fibers... 

The inorganic flash reducers (such.as K sulfate) were usually loaded in small bags separately from the propint, and placed between the projectile and the propint. These anti-flash bags, called in German "Vorlage , consisted of two perforated discs of artificial silk or cotton cloth sewn together in (he form of doughnuts and filled with coarsely pulverized K sulfate. (Ref 1, p 324)... 

Absorption of solvent with sulphuric acid. This is another of the oldest methods for the recovery of solvent. It was first used for the recovery of alcohol and ether in the manufacture of artificial silk by the old Chardonnet process and was then widely applied in the manufacture of powder in Germany and Austria before and during World War I. The air containing alcohol and ether entered the tanks filled with sulphuric acid. The tanks were cooled from outside by spraying with water. 

The Germans used anti-flash charges containing potassium chloride in their cannon propellants. The charges, in bags of artificial silk or cotton cloth, were loaded between the base of the projectile and the propellant. Obviously, all the additions described above increased the smoke formed when the rounds were fired. 

Nitro-3,4-dimethoxyaniline (called 4-Amino-5-nitroveratrole by Nakamura et al and 5-Nitro-4-amino-brenzeatechin-dimethyl-ather in Ger), nm-colored prisms or terracotta ndls (from ale), mp 169-75° (Refs 3 6) 4-Niiro-2,3-dimethoxyaniline. Its use as an excellent fast dye on acetate artificial silk is described. No other info given in patent abstract (4)... 

The gas is used in various chemical industries. For example, it forms an intermediate stage in the production of sulphuric acid and of sulphites it is also applied in the preparation of chemical substances such as selenium, tellurium, quinol, etc. To some extent sulphur dioxide finds application for fire-prevention and -extinguishing, and much is used in the form of alkali sulphite in the production of wood pulp for paper and artificial silk manufacture. 

CHARDONNET, H. (1839-1924). A native of France, he has been called the lather of rayon because of his successful research in producing what was then called artificial silk from nitrocellulose. He was able in extrude fine threads of this semi-synthetic material through a spinnetetle-like nozzle, and Ihe textile product was made on a commercial scale in several European countries. He was awarded Ihe Perkin medal for his work... 

Of the numerous textile fibres known, relatively few are of commercial importance, the principal ones being cotton, flax, hemp, ramie, jute, wool, silk and artificial silk. These fibres are used to make the different kinds of yarn from which fabrics of various types are woven. 

Preparation of Sections of the Fibres.—Identification of animal or vegetable fibres is based mainly on the physical characters, the fibres being mostly so transparent that their form and structure, and particularly the thickness of the walls and the form of the internal canal or lumen, are easily observed. In some cases, however, owing to the close resemblance between certain fibres, recognition is doubtful. This is the case, for instance, with the poorer qualities of flax and hemp, and with certain types of artificial silk. In these instances the transverse sections of the fibres are studied, these permitting of observation of the thickness of the walls, the strata... 

The basic substance of the fibre is nitrocellulose (pyroxylin) Char-donnet, Vivier, Lehner and Cadoret artificial silks. 

Other artificial silks are made with animal gelatines by the Millar and Hummel processes (Vandura silk), but these are now of no commercial importance. 

Artificial silks have a characteristic microscopic appearance which renders easy their distinction from other fibres in general and from ordinary silk in particular. The principal difference is the large diameter, but it must be borne in mind that when preparations are made in water, as is usually the case, the fibres swell considerably. 

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