Calcium thiocyanate

Aqueous salt solutions such as saturated 2inc chloride [7646-85-7] or calcium thiocyanate [2092-16-2] can dissolve limited amounts of cellulose (87). Two non-aqueous salt solutions are ammonium thiocyanate [1762-95-4]— uoamonia. and lithium chloride /744Z-4/A/—dimethyl acetamide [127-19-5]. Solutions up to about 15% can be made with these solvents. Trifluoroacetic acid [76-05-17—methylene chloride [75-09-2] and /V-methy1morpho1ine N-oxide [7529-22-8]—(92—94) are two other solvent systems that have been studied (95). 

With sulfur in aqueous medium, calcium cyanide forms calcium thiocyanate [2092-16-2]... 

Rhodan-ion, n. thiocyanogen ion, CNS -kali, -kalium, n, potassium thiocyanate, -kalzium, n. calcium thiocyanate, -kupfer, n. cupric thiocyanate, copper(II) thiocyanate. -iSsung, /. thiocyanate solution, -metall, n. (metallic) thiocyanate, -methyl, n. methyl thiocyanate, -natrium, n, sodium thiocyanate, -nickel, m. nickel thiocyanate, -quecksilber, n. mercury thiocyanate, -salz, n. thiocyanate, -sdure, /. (Org. Chem.) thiocyan(at)o acid, -tonerde, /. aluminum thiocyanate. 

Most linear celluloses may be dissolved in solvents capable of breaking the strong hydrogen bonds. These solutions include aqueous solutions of inorganic acids, calcium thiocyanate, zinc chloride, lithium chloride, ammonium hydroxide, iron sodium tartrate, and cadmium or copper ammonium hydroxide (Schweitzer s reagent). The product precipitated by the addition of a nonsolvent to these solutions is a highly amorphous, regenerated cellulose. 

Cellulose N,N-Dimethyl acetamide (100 ml)/lithium chloride (5 g), aqueous tetraaminecopper(II) hydroxide, aqueous zinc chloride, aqueous calcium thiocyanate Acetone, methanol, water... 

This category of admixture is based mainly on the major raw materials, calcium chloride, calcium nitrate, calcium formate [2] and calcium thiocyanate, with minor amounts of other materials occasionally being included in the formulations, such as calcium thiosulfate [3] and triethanolamine (TEA). TEA is not normally used alone but because it is sometimes used in other categories of admixture to compensate for retarding influences it will be included in this section. 

Sodium, potassium, barium, or calcium thiocyanate may be made by reaction of sulfur and the corresponding cyanide by heating to fusion. Ammonium thiocyanate (plus ammonium sulfide) may be made by reaction of ammonia and carbon disulfide, a reaction which probably accounts for tlie presence of ammonium thiocyanate in the products of the destructive distillation of coal. This reaction corresponds to the formation of ammonium evanate from ammonia and carbon dioxide. 

Bone black which has been recently prepared and not washed contains small quantities of calcium cyanide, which may be detected by extracting about 200 grams of the pigment with cold water and evaporating the filtrate to very small volume with a few drops of ammonium sulphide this procedure yields calcium thiocyanate, which is recognisable by its reaction with ferric chloride. 

Chekhlov, A. N. (2000) Crystal structure of the l,10-diaza-18-crown-6 complex with calcium thiocyanate, Russ.J. Coord. Chem. 26, 157-161. 

Aqueous salt solutions such as saturated zinc chloride or calcium thiocyanate can dissolve limited amounts of cellulose [131]. Two nonaqueous salt solutions with a lengthy history are ammonium thiocyanate/ammonia and dimethylacetamide/lithium chloride (DMAc/LiCl). Solutions up to about 15% can be prepared with these solvents. DMAc-LiCl has been used for molecular weight determinations of cotton [135] (see Section 1.5.2). 

CALCIUM SULFOCYANATE see CAY250 CALCIUM SUPEROXIDE see CAV500 CALCIUM THIOCYANATE see CAY250 CALCIUM TRISODIUM CHEL 330 see CAY500... 

Calcium Thiocyanate 2092-16-2 Chloric Acid 7790-93-4 Chromyl Chloride 14977-61-8... 

Aluminum Ammonium Sulfate 2092-16-2 Calcium Thiocyanate Soarnol DT... 

In the study of Hannon and Wissbrun (10), which forms another point of departure for this work, a range of properties was investigated for the phenoxy-calcium thiocyanate system. The glass transition was observed to increase at a rate of 1.8°/mol % salt this, and the absence of negative deviations from additivity of specific volume, suggests that the interactions here are weaker than those in the systems studied by Moacanin and Cuddihy. The viscosity behavior reflected exclusively the increase in Tg. A strong shear-rate dependence of the viscosity was observed over the entire 40° range (170°-210°C) studied, and even at the lowest shear rates (3 X lO sec"1) the curves did not approach zero shear behavior. The samples could not be studied above 210 °C because of incipient decomposition. 

The calcium/thiocyanate isotherms, combined with contact angle measurements, reveal, on a molecular level, any rearrangement or reorientation of surface functional groups produced by the variation or alternation of the polymer adjacent phase. The main references to these studies are given in (1-5). 

In polyacrylonitrile appreciable electrostatic forces occur between the dipoles of adjacent nitrile groups on the same polymer molecule. This restricts the bond rotation and leads to a stiff, rodKke structme of the polymer chain. As a result, polyacrylonitrile has a very high crystalline melting point (317°C) and is soluble in only a few solvents, such as dimethylformamide and dimethylacetamide, and in concentrated aqueous solutions of inorganic salts, such as calcium thiocyanate, sodium perchlorate, and zinc chloride. Polyacrylonitrile cannot be melt processed because its decomposition temperature is close to the melting point. Fibers are therefore spun from solution by either wet or dry spinning (see Chapter 2). 

Cellulose Aqueous cupriammonium hydroxide, aqueous zinc chloride, aqueous calcium thiocyanate Methanol, acetone... 

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