Ammoniacal cellulose

Copper proteins, 1,168 5,720 models, 2,85 nonblue, 5,723 type 111, 5,724 Copper salts cellulose dyes, 6,38 Copper(I) salts stabilization, 6,786 Copper(II) salts ammoniacal leaching, 6,787 oxidant... 

During preparation of an oxidising agent on a larger scale than described [1], addition of warm sodium hydroxide solution to warm ammoniacal silver nitrate with stirring caused immediate precipitation of black silver nitride which exploded [2], Similar incidents had been reported previously [3], including one where explosion appeared to be initiated by addition of Devarda s alloy (Al—Cu—Zn) [4], The explosive species separates at pH values above 12.9, only produced when alkali is added to ammoniacal silver solutions, or when silver oxide is dissolved with ammonia [5], The Sommer Market reagent mixture used to identify cellulose derivatives led to a severe explosion [6],... 

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... 

In 1857, Schweizer discovered that ammoniacal solutions of copper hydroxide could dissolve cellulose. Cellulose is a versatile polymer which is found in plenty in nature in the form of cotton, hemp, jute, flax, etc. In 1891, first attempts were made to spin a solution of cellulose. The cellulose produced like this is known as Bemberg Rayon and is still being produced commercially in Germany, Italy, Japan and USA. 

Schweitzer s reagent chem An ammoniacal solution of cupric hydroxide used to dissolve cellulose, silk, and linen, and to test for wool. shvTt-sorz re,a- 3nt scopoline orgchem CgHijOjH A white crystalline alkaloid that melts at 108-109°C, soluble in water and ethanol used in medicine. Also known as oscine. sko-p3,len ... 

Another typical property of cellulose and its derivatives dependent on water sorption is the swelling of the fibre that occurs under the influence of certain solutions such as aqueous sodium hydroxide or an ammoniacal solution of cupric oxide, i.e. cuprammonium . The process of swelling does not start with sorption as in the instance of water. In the first stage of swelling the liquid penetrates the molecular chains of the cellulose, gradually coming in contact with all of them so that chemical combination takes place to form alkali celluloses, (C6H,0O5) NaOH and (C6H,0O5)2 NaOH. 

Solutions of cellulose derivatives, such as nitrocellulose, passed through a fine porous filter demonstrate neither the Tyndall effect, nor the presence of particles visible in the ultra-microscope. This is one more piece of evidence that the properties of these solutions are the same as those of substances with low molecular weight. The same holds for cellulose in ammoniacal solutions of cupric oxide ( cupr-ammonium ). 

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. 

Cotton. Cotton is furnished by the down surrounding the seeds of various species of Gossypium. This fibre, which is unicellular and closed at only one end, is always isolated, and appears under the microscope as a ribbon twisted at intervals on its own axis like a spiral (Fig. 68, Plate VI). The wall is comparatively thin and sometimes somewhat raised like a rim the lumen is wide—three or four times as wide as the walls. This lumen is mostly empty, but sometimes contains granulations representing the original protoplasm in a dried state. The cotton fibre, which consists solely of cellulose, is coated in the raw state with a very thin cuticle, which is readily seen in a dry microscopic preparation. When raw cotton is treated with ammoniacal cupric oxide solution, whilst the cellulose of the fibre first swells and then dissolves, the cuticle remains almost intact, so that the fibres assume characteristic microscopic forms. The section of the cotton fibre (see Fig. 69, Plate VI) is elliptical, curved or reniform, with a fissure-like lumen. 

Schweitzer s Reagent.—Chemically it is an inert compound wholly insoluble in water, most neutral reagents and in dilute acids or alkalies under ordinary conditions. It is probable that no solvent dissolves cellulose without decomposition or hydration. The solvent most commonly used is an ammoniacal solution of copper oxide made by dissolving freshly precipitated copper hydroxide in ammonium hydroxide. This solution is known as Schweitzer s reagent. After solution in this reagent acids reprecipitate the cellulose as a hydrated cellulose. 

Glaessner, Austria, 1931), ammoniacal bleached shellac (Wruble, 1933), stearic acid, carnauba wax, petrolatum, elm bark, and agar (Miller, 1935, and Worton, 1938), and abietic, oleic, and benzoic acids with methyl abietate (Eldred, 1937). Since 1940, research on enteric coatings has focused on the synthesis of resinous polymers, which are insoluble in acids, such as cellulose acetate phthalate (Hiatt, 1940) and a glycerol-stearic acid-phthalic anhydride ester (Volweiler and Moore, 1940). 

An important process is the manufacture of regenerated cellulose applied to make fibers (e.g., rayon) and films (e.g., Cellophane). Solvents used classically in cellulose regeneration are a mixture of carbon disulfide and sodium hydroxide or ammoniacal copper solutions. More recent solvents include N-methylmorpholine-N-oxide and phosphoric acid [4]. The cellulose solution is extruded through nozzles into an acidic precipitation bath and is spun into fibers. Recently, the partly toxic and strongsmelling solvents have been replaced by ionic liquids which are even able to improve the solubility of the slightly soluble cellulose [10]. For example, 1 1 of l-butyl-3-methylimidazolium chloride dissolves lOOg of cellulose at 100°C [11],... 

Cellulose is not affected by ordinary solvents, but is attacked by strong sulphuric acid, yielding a starch-like body called amyloid, and is dissolved by ammoniacal solutions of copper salts, from which it can be precipitated in an amorphous form by the addition of acids. This properly constitutes the basis of one method of making artificial silk. It may be mentioned, incidentally, that when heated to 200-220 deg. Cent, with caustic potash, cellulose is broken down into oxalic acid, and large quantities of that acid are made in this way. Sawdust is fused with potash in iron pans the melt when cold is extracted with water, and the oxalic acid is precipitated as the insoluble calcium salt from which it is subsequently liberated by the action of sulphuric acid. This process, which was discovered by Gay-Lussac in 1829, and was first employed on the manufacturing scale by Dale- in 1856, is far cheaper than the older method of oxidising sugar or starch with nitric acid. "... 

This disintegration of the albuminoid substance, which converts almost the whole of the organic nitrogen into ammonia, results from the combined action of numerous micro-organisms, of different species and nature. The products elaborated by one class of bacteria often serve as the point of attack for another. Thus the volatile acids and oxyacids furni.shed in the course of ammoniacal fermentation constitute a nutritive rruitcrial for the ferments of cellulose, bacteria abundantly represented in the soil Calcium acetate, as well as its homologues, react under these conditions in the following manner ... 

In another process, cellulose is dissolved in ammoniacal cupric hydroxide (Cu(NH3>4(OH)2). The solution is then spun as a fiber into a dilute sulfuric acid solution to regenerate the cellulose. The product is called Cuprammonium rayon. The material may still be manufactured on a limited scale. 

Ammoniacal copper sulfate Anthracene Cadmium chloride Potassium ferricyanide printing, cellulosic textiles p-Phenylenediamine dihydrochloride printing, plasticized fabrics 2-Hexanone printing, security Benzidine dihydrochloride printing, textile industrial Propylene glycol alginate printing, textiles... 

Cellulose 111 (ammoniacal cellulose) Careful degradation of ammoniacal cellulose (from 11 with NH3) 0.774 0.99 1.03 122.00... 

Chief constituent of the cellular tissue or fibre of plants. Cotton is the purest natural form and contains about 90%. Flax, hemp, ramie, etc., are less pure forms. Present in wood and straw (30-40%). The action of 17-18% NaOH dis-tinguishes three celluloses, viz. a c ulose (insol), cellulose (sol. and re-pptd. by acids), and y>cellulose (permanently sol.). a-Cellulose is that normally referred to as pure cellulose. It is insol. in all ord. org. solvents, but dissolves in cold 70% HgS04 (re-pptd on dilution— hydrocellulose), cone. ZnGg-Aq., ammoniacal copper hydroxide sol. (Schweizer s reagent), and in NaOH + CS2 (forms sodium xanthogenate). Does not react with phenylhydrazine or hydr-oxylamine. TaJres up one mol. NaOH for each CgHipOs unit, the NaOH being recovered by... 

John Mercer (Dean or Great Harwood, nr. Bolton, Lancs., 21 February 1791-Oakenshaw, Lancs., 30 November 1866), a calico-printer, discovered mercerising (1844), the use of potassium ferrocyanide and potash for the discharge of indigo (1848), the use of arsenates as a substitute for phosphates in dunging the manufacture of sodium stannite and stannate, stannous sulphate from tin and copper sulphate solution, Turkey-red oil, the solubility of cellulose in ammoniacal copper solution, and blue-print photography. He taught himself chemistry from a second-hand copy of the Chemical Pocket-Book of James Parkinson, of Hoxton Square, London (2 ed. 1801, 3 ed. 1803). ... 

---