Polymetaphosphates

Glassy phosphates (sodium polymetaphosphate [50813-16-6] sodium hexametaphosphate [10124-56-8J) vary in composition, depending upon the... 

A rather different structure-motif is observed in the chain polyphosphates these feature comer-shared PO4 tetrahedra as in the polyphosphoric acids (p. 522). The general formula for such anions is [Pn03 4.i] + , of which the diphosphates, P2O7 ", and tripolyphosphates, PsOjo , constitute the first two members. Chain polyphosphates have been isolated with n up to 10 and with n infinite , but those of intermediate chain length (10 < n < 50) can only be obtained as glassy or amorphous mixtures. As the chain length increases, the ratio (3n + l)/n approaches 3.00 and the formula approaches that of the polymetaphosphates [P03 ]oo-... 

Thermolytic processes are so far known to play only a minor role in the generation of the PO ion. An isolated case is the thermolysis of the monosodium salt of acetonylphosphonic acid at 150 °C, which leads to acetone and sodium polymetaphosphate 107). A cyclic fragmentation mechanism, as known for P-ketocarboxylic acids, could lead to PO in this case. 

Potassium peroxomonosulfate, 14 67 Potassium peroxydisulfate, 14 292 Potassium peroxymonosulfate, 26 189 Potassium persulfate, 7 856 Potassium phosphates, 18 834-835 20 637 manufacture of, 18 854 Potassium polymetaphosphate, 18 848 Potassium products, 20 5991 Potassium pyrophosphates, 18 843 Potassium residues, 20 603 Potassium salts, 20 609... 

Sodium phosphate(s), 28 831-834, 29 18 carbon dioxide by-product of manufacture, 4 810 economic aspects of, 28 860 uses for, 28 833-834 Sodium polybutadiene, 9 555, 556 Sodium polymetaphosphate, 8 416 Sodium polyphosphates, 9 16 manufacture of, 28 858 Sodium polyphosphate glass, 28 851 Sodium polystyrene sulfonate cosmetic surfactant, 7 835t Sodium polysulfide(s), 23 640 in sodium production, 22 773 Sodium-potassium eutectic, 15 252... 

A variety of other glassy inorganic polymers are known [Ray, 1978]. Polymetaphosphates are linear polymers produced by heating an alkali dihydrogen phosphate (Eq. 2-232). 

Muhammed, A. Studies on biosynthesis of polymetaphosphate by an enzyme from Corynebacterium xerosis. Biochim. Biophys. Acta, 54, 121-132 (1961)... 

Polyvinylpolypyrrolidone Potassium Alginate Potassium Citrate Potassium Polymetaphosphate Potassium Tripolyphosphate Povidone PVP... 

Polymetaphosphate 3 Polymorphonuclear leukocytes 26 Polynucleotide(s) 199s, 226-228. See also Nucleic acids, RNA, DNA hybridization 255 hydrazine reactions 254 interactions with ions 218 melting of 255 probes 255... 

There is some doubt if some of the polymetaphosphates are really chemical individuals, and if some of the individual metaphosphates have been inserted in the right class. Decisive evidence is usually wanting, for, in spite of the many researches which have been made on the metaphosphates, their chemistry is by no means in a satisfactory condition. As F. Warschauer said in 1903, the meta-phosphates form one of the most confused chapters of inorganic chemistry. 

Synonyms Graham s salt, Sodium hexametaphosphate, Sodium polymetaphosphate. Appearance White flaky crystals or granules small, broken, glass-like particles. 

POsF(NH4)2 Ammonium mono-fluorophosphate, 2 155 P03FNa2 Sodium monofluorophos-phate, 3 106, 108 POaHa Phosphorous acid, 4 55 P03NH2(C2Hj)2 Diethyl mono-amidophosphate, 4 77 (POaNa) Sodium polymetaphosphate, 3 104... 

E. Esposito and P. Wison (1956). Calcium and polymetaphosphate synthesis in Azotobacter vinelandii. Biochem. Biophys. Acta, 22, 186-191. 

B. IngeLman (1948). Isolation of polymetaphosphate of high molecular weight from Aspergillus... 

B. Ingelman and H. Malmgren (1947). Enzymatic breakdown of polymetaphosphate. I. Acta Chem. Scand., 1, 422 132. 

H. Malmgren (1952). Enzymatic breackdown of polymetaphosphate. V. Purification and specificity of the enzyme. Acta Chem. Scand., 6, 16-26. 

The polymetaphosphates are distinguished by giving gelatinous precipitates with salts of most metals, and by decolorising red solutions containing Fe(CNS)3.9... 

Potassium Polymetaphosphate occurs as a white powder. It is a straight-chain polyphosphate having a high degree of polymerization. It is insoluble in water, but is soluble in dilute solutions of sodium salts. 

Glassy phosphates (sodium polymetaphosphate, sodium hexametaphosphate) vary in composition, depending on the manufacturing process. They exert a powerful sequestering and suspending effect combined with a low-solution pH, about 6 or 7, and tend to hydrolyze or revert in aqueous solution and heat to pyrophosphates and orthophosphates. 

Audrieth and Moeller (61) have applied the Lewis concept to poly acids, and Hill and Audrieth (62) have shown that fluoride acts as a strong anionic base and catalyzes the high-temperature depolymerization of the polymetaphosphate and polyphosphate in the fused state. 

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