Nitrocellulose fibers

The first successhil attempt to make textile fibers from plant cellulose can be traced to George Audemars (1). In 1855 he dissolved the nitrated form of cellulose in ether and alcohol and discovered that fibers were formed as the dope was drawn into the air. These soft strong nitrocellulose fibers could be woven into fabrics but had a serious drawback they were explosive, nitrated cellulose being the basis of gun-cotton (see Cellulose esters, inorganic esters). 

The mixer serves three purposes. First, it blends all the ingredients to provide uniform distribution in the final propellant. Second, it provides time, heat, and contact for solvation of all or part of the nitrocellulose by the volatile solvent and plasticizer. Third, it provides mechanical energy to disrupt nitrocellulose fibers and expose them to solvation. Solvated nitrocellulose is the matrix which bonds the rest of the material together and eventually gives strength and elasticity to the finished propellant. 

Figure 62. Nitrocellulose Fibers before Beating (132X) (Courtesy Western Cartridge Company.)...

Bulk powders are made in considerable variety, but they consist always of nitrocellulose fibers which are stuck together but are not completely colloided. Some contain little else but nitrocellulose others contain, in addition to potassium and barium nitrates, camphor, vaseline, paraffin, lampblack, starch, dextrine, potassium dichromate or other oxidizing or deterrent salts, and diphenylamine for stabilization, and are colored in a variety of brilliant hues by means of coal-tar dyes. In the United States bulk powders are manufactured by one or the other of two processes, either one of which, however, may be modified considerably the materials are incorporated under wooden wheels, grained, and partially gelatinized, or the grains arc formed in a still where a water suspension of ptdped nitrocellulose is stirred and heated with a second liquid, a solvent for nitrocellulose which is volatile and immiscible with water. 

Cellulose acetate monofilament, yarn, staple, or tow Cellulose fibers, manmade Cigarette tow, cellulosic fiber Cuprammonium fibers Fibers, rayon Horeshair, artificial rayon Nitrocellulose fibers Rayon primary products fibers, straw, strips, and yarn... 

In 1920, the Tubize Company built a plant to produce the yarn in the United States. By 1934, however, other types of superior rayon had been developed, so the nitrocellulose plant was sold to a company in Brazil. Several incidents of explosions and fires caused by the incompletely denitrated cellulose resulted in setbacks to the Chardonnet silk process, but, fortunately, the simultaneous development of cuprammonium and viscose solutions for spinning rayon rapidly replaced the more dangerous nitrocellulose fibers. 

In 1845, German Swiss chemist C. F. Schonbein accidentally discovered the explosive properties of nitrocellulose fibers when he used his wife s cotton apron to mop up some nitric acid, then hung the apron by a stove to dry. 

The beater additive process starts with a very dilute aqueous slurry of fibrous nitrocellulose, kraft process woodpulp, and a stabilizer such as diphenylamine in a felting tank. A solution of resin such as poly(vinyl acetate) is added to the slurry of these components. The next step, felting, involves use of a fine metal screen in the shape of the inner dimensions of the final molded part. The screen is lowered into the slurry. A vacuum is appHed which causes the fibrous materials to be deposited on the form. The form is pulled out after a required thickness of felt is deposited, and the wet, low density felt removed from the form. The felt is then molded in a matched metal mold by the appHcation of heat and pressure which serves to remove moisture, set the resin, and press the fibers into near final shape (180—182). 

Sir Joseph Swan, as a result of his quest for carbon fiber for lamp filaments (2), learned how to denitrate nitrocellulose using ammonium sulfide. In 1885 he exhibited the first textiles made from this new artificial sHk, but with carbon fiber being his main theme he failed to foUow up on the textile possibihties. Meanwhile Count Hilaire de Chardoimet (3) was researching the nitrocellulose route and had perfected his first fibers and textiles in time for the Paris Exhibition in 1889. There he got the necessary financial backing for the first Chardoimet silk factory in Besancon in 1890. His process involved treating mulberry leaves with nitric and sulfuric acids to form cellulose nitrate which could be dissolved in ether and alcohol. This collodion solution could be extmded through holes in a spinneret into warm air where solvent evaporation led to the formation of soHd cellulose nitrate filaments. 

Nitrocellulose is always in motion in the digester and well suspended in water, so that each fiber receives uniform treatment, producing a uniform viscosity much superior to the batch product. The continuous product has no oppor-... 

Used in agriculture as a fertilizer and defoliant in the manufacture of nitric acid, hydrazine, hydrogen cyanide, urethanes, acrylonitrile, nitrocellulose, nitroparaffins, melamine, ethylene diamine, and sodium carbonate as an intermediate in producing explosives, synthetic fibers and dyes and used industrially as a refrigerant gas, neutralizing agent in the petroleum industry, latex preservative, and the production of fuel cells. 

Okra, Hibiscus escuentus L. The immature pods of okra are popular as a vegetable and okra is also used for the ability to thicken soups and stews, and for fiber and oil. Notmuch is known about okra most workers concentrate their research on the chemical composition (26-29) of the mucilaginous materials found in the pod (30) stalk, nutritional properties (31). Research has also been conducted on the developmental properties of the okra seed (32). This paper is the first report of the chemical composition of auxin conjugates in okra pods bound to nitrocellulose membrane. 

Uses Manufacture of acrylonitrile, hydrazine hydrate, hydrogen cyanide, nitric acid, sodium carbonate, urethane, explosives, synthetic fibers, fertilizers refrigerant condensation catalyst dyeing neutralizing agent synthetic fibers latex preservative fuel cells, rocket fuel nitrocellulose nitroparaffins ethylenediamine, melamine sulfite cooking liquors developing diazo films yeast nutrient. 

The development of plastics accompanied synthetic fibers. The first synthetic plastic with the trade name Celluloid was made in 1870 from a form of nitrocellulose called pyroxylin, the same substance used to produce the first rayon. Celluloid was developed in part to meet the demand for expensive billiard balls, which at the end of the nineteenth century were produced from ivory obtained from elephant tusks. John Wesley Hyatt (1837-1920) combined pyroxylin with ether and alcohol to produce a hard substance called collodion. Hyatt s collodion, like Bernigaut s original rayon, was unstable and potentially explosive. He solved this problem by adding camphor to the collodion to produce a stable hard plastic he called Celluloid. 

Cellulose dissolves in Schweitzer s reagent, an ammoniacal solution of cupric oxide. After treatment with an alkali, ibe addition of carbon disulfide causes formation of sodium xanihate. a process used in the production of rayon. Sec also Fibers. The action of acetic anhydride in the presence of sulfuric acid produces cellulose acetates, the basis for a line of synthetic materials. See also Cellulose Ester Plastics (Organic). Nitrocelluloses are produced hy ihc action of nitric acid and sulfuric acid on cellulose, yielding compounds that are highly flammable and explosive. See also Explosives. 

Adsorb the antibody to a solid support such as the surface of a plastic tube, multiwell plate, latex particle, magnetic particle, nylon, nitrocellulose, or glass fiber filter. 

Ugnosulfonates Plant fibers and meals Glycerin Nitrocellulose Gilsonite... 

Soak the nitrocellulose membrane for 15-20 min in transfer buffer. Also wet two Scotch-Brite fiber pads, gel and filter papers in transfer buffer. 

Assemble the sandwich for transfer in this order fiber pad, filter paper, nitrocellulose, gel, filter paper, and fiber pad. Remove all air bubbles between membrane and gel and between paper and gel. 

Nitrocellulose and Cellulose Acetate. Although nitrocellulose and cellulose acetate intermediates have been made and regenerated to form cellulose fibers, neither of these historical processes is still in operation. 

---