Cuprammonium cellulose

The dark blue solution containing 5—10% of cellulose with a DP of 1000—2000 is filtered through a series of plate-and-frame filter presses using fine mesh metal screens to remove any particles that might block the spinneret holes. It is then deaerated under vacuum and stored ready for spinning. Unlike viscose dope, the cuprammonium cellulose [9050-09-3] solution is relatively stable. 

The methyl ester of oxycellulose, produced by alkaline permanganate oxidation of cuprammonium cellulose followed by treatment with diazomethane, has been reacted with protein by the azide method [34]. Acidic oxyce]]uloses are aiso able to react with alcohols and amines, including proteins, to form esters or amide derivatives. 

Daugirdas JT, Ing TS, Roxe DM, Ivanovich PT, Krumlovsky F, Popli S, McLaughlin MM. Severe anaphylactoid reactions to cuprammonium cellulose hemodialyzers. Arch Intern Med 1985 145(3) 489-94. 

Cuprammonium cellulose is a constituent of some dialysis membranes (1). 

Albumin, cellulose acetates, cuprammonium cellulose, chito-sans, collagen, fibrin, elastin, gelatin, hyaluronic acid, phospholipids, silk... 

Cellulose dissolves in strong mineral acids, in NaOH and in cuprammonium solution. It forms a triacetate (tri-ethanoate), a trinitrate... 

Schweizer s reagent The dark blue solution obtained by dissolving Cu(OH)2 in concentrated ammonia solution. Used as a solvent for cellulose, the cellulose is precipitated on acidification. Used in the cuprammonium process for the manufacture of rayon. 

Of somewhat greater technical interest are the addition compounds and the cellulose esters and ethers. Of the apparent addition compounds the most important is alkali cellulose produced by steeping cellulose in caustic soda and considered to be of general form (CgHioOs), (NaOH) ) rather than a sodium alcoholate compound. Alkali cellulose is a particularly important starting point in the manufacture of cellulose ethers. The ability of aqueous cuprammonium hydroxide solutions to dissolve cellulose appears to be dependent on addition compound formation. 

Dissolution of the cellulose in cuprammonium solution followed by acid coagulation of extruded fibre ( cuprammonium rayon —no longer of commercial importance). In this case the acid converts the cuprammonium complex back into cellulose. 

The presence of free sulphuric acid in rayon-spinning baths limits application of the austenitic steels, but they are used for acetylation of cellulose in the acetate process. They are also used for dissolving and spinning solutions in the cuprammonium processes. 

Chitosan features far more than chitin in research into applications. This is largely due to their difference in solubility characteristics, chitosan being more amenable to practical manipulation. Chitin is in fact rather more intractable than cellulose, since it is insoluble in those solvents, such as cuprammonium hydroxide, that are commonly used to dissolve cellulose. Chitin is soluble in hot concentrated solutions of certain inorganic salts capable of... 

In 1886, Brown11 discovered an organism which formed extremely tough membranes when cultivated m suitable nutrient solutions containing carbohydrates such as D-fructose, D-mannitol or D-glucose ethanol, sucrose or starch did not support membrane formation by this organism which Brown called Bacterium xylinum ) (Acetobacter xylinum). The membranes were readily soluble in cuprammonium hydroxide solution and yielded a dextrorotatory sugar upon acid hydrolysis. These properties and the results of combustion analysis led him to believe that the membrane was cellulose. 

This term was originally intended to denote all kinds of man-made textile fibres, but is now applied only to cellulose types. Viscose rayon (regenerated from a solution of cellulose xanthate in sodium hydroxide) accounts for the greater part of world rayon production. Acetate rayon and cuprammonium rayon are relatively unimportant. 

Cuprammonium A process for making regenerated cellulose fibers. Cellulose, from cotton or wood, is dissolved in ammoniacal copper sulfate solution (Schweizer s reagent, also called cuprammonium sulfate). Injection of this solution into a bath of dilute sulfuric acid... 

Amorphous Cellulose in Cotton and Cuprammonium Rayon by Periodate Oxidation"... 

Goldfinger and coworkers obtained the data shown in Table IX by this method. The difference in amorphous cellulose between linters and cotton is appreciable but attention is directed particularly to the behavior of cuprammonium rayon after being dried from water and after being... 

Cellulose is used in the textile industry in cloths, cartons, carpets, blankets, and sheets. Paper is made from cellulose. Cellulosic fibers are also used as filter materials in artificial kidneys and reverse osmosis though today most kidney dialysis units use cuprammonium tubular films derived from cellulose rather than cellulose itself. 

An alternate procedure used in a few specialty applications is the cuprammonium process. This involves stabilization of cellulose in an ammonia solution of cupric oxide. Solubilization occurs by complex formation of cupric ion with ammonia and the hydroxyl groups of cellulose. Regeneration of cellulose, after formation of the desired products, is accomplished by treatment with acid. The main application of the cuprammonium process is for the synthesis of films and hollow fibers for use in artificial kidney dialysis machines. The cuprammonium process yields products with superior permeability and biocompatibility properties compared to the xanthation process. Less than 1% of all regenerated cellulose is produced by the cuprammonium process. 

Ami noethylation of Cellulose Derivatives and of Reaenerated Cellulose Cellulose obtained by regeneration from a cuprammonium soln of cotton(in the manner described in Rept No 2,p 14) from the Wyandotte Chem Corp gave an amorphous product contg ca 23.5% N when heated with ethyleneimine in a sealed tube at 120° in the presence of toluene. The cellulose derivatives catboxy-me thy (cellulose and hydroxyetbylcellulose (prepd in the manner described in Rept No 3, pp 14—18) gave solid products with nitrogen contents of 24.8 and 28.1% respectively, when heated with ethyleneimine in a sealed tube, in the manner described in Rept No 1,... 

Some data for the molecular weight of cellulose of various origins determined by ultra-centrifuging cuprammonium solution, are given in Table 35. 

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