Phosphorus, 142 rayon

Mention has already been made of the application of alkoxycyclophos-phazenes, [NP(OR)2] , as flame retardants in rayon. Although the methoxy-derivatives, with their high phosphorus content, were expected to be most efficient in this respect, their water solubility proved a major shortcoming. However, the n-propoxy series, [NP(OPr )2] ( mainly 3—6), were found to impart excellent flame resistance and were well retained by rayon. The cyclophosphazene alkoxides were obtained by the addition of sodium-n-propoxide to the chloride homologues, (NPCl2)n, and were added to the viscose dope before the rayon was spun. The flame resistance imparted by various amino- and thioalkoxy-derivatives was also tested, but found to be inferior to the results obtained with alkoxy-deriva-tives. Several patent applications have resulted from work on this topic. ... 

Used industrially as a chemical intermediate in the production of rayon, carbon tetrachloride, xanthogenates, flotation agents, and pesticides used in the cold vulcanization of vulcanized rubber, in adhesive compositions for food packaging as a solvent for phosphorus, sulfur, selenium, bromine, iodine, fats, resins, rubbers, waxes, lacquers, camphor, resins and in the production of optical glass, paints, enamels, varnishes, paint removers, tallow, putty preservatives, rubber cement, soil disinfectants, explosives, rocket fuel, and electronic vacuum tubes. 

Uses Manufacture of viscose rayon, cellophane, flotation agents, ammonium salts, carbon tetrachloride, carbanilide, paints, enamels, paint removers, varnishes, tallow, textiles, rocket fuel, soil disinfectants, electronic vacuum tubes, herbicides grain fumigants solvent for fats, resins, phosphorus, sulfur, bromine, iodine, and rubber petroleum and coal tar refining solvent and eluant for organics adsorbed on charcoal for air analysis. 

Uses. Manufacture of rayon viscose fibers and cellophane film solvent for lipids, sulfur, rubber, phosphorus, oils, resins, and waxes insecticide... 

In order to limit extensive side reactions (advanced destruction of the support-polymer, modification of grafting monomers structure) which usually accompany grafting reactions in electrical discharge conditions, we have elaborated the solid-solid grafting procedure in cold plasma. Thus, the rayon fabric was grafted with halogen and phosphorus containing polymers in... 

There are, of course, other methods for treating fibers and rayon fabrics with organo-phosphorus compounds (9-13) in order to improve their flame-retardant properties. However, the modified fibers present the changed physical and mechanical properties due to large additives utilised and often these additives are eliminated after repeated washings. 

In this paper, the surface grafting of rayon fabrics with nitrogen and phosphorus containing polymers in cold plasma is studied. The analytical data (IR spectroscopy, TGA, electron microscopy, elemental analysis, etc.) indicate the formation of grafted copolymers. The grafted rayon fabrics present improved flame-retardant properties, the best behavior was proved by those grafted with polyurea of phosphinic acid. 

Grafting experimental conditions and phosphorus and nitrogen contents of the plasma grafted rayon fabrics ... 

The elemental analysis also shows low nitrogen and phosphorus contents of these fractions, due probably to bound or enclosed polymer fragments into the structure of the rayon fabrics and to the fact that the grafting agents are sufficiently resistant at the hydrolysis. 

Viscose or rayon A well-known inherently FR viscose fiber is Viscose FR, marketed by Lenzing. The fiber is produced by adding Sandoz 5060 (Clariant 5060)-bis(2-thio-5,5-dimethyl-l,3,2-dioxa-phosphorinyl)oxide in the spinning dope before extrusion. As this additive is phosphorus based, it is similar to other phosphorus-based FRs in terms of mode of action (condensed phase). 

Simionescu, C.I., Denes, F., Macoveanu, M.M., Cazacu, G., Totolin, M., Percec, S., and Balaur, D. 1980. Grafting of rayon fabrics with phosphorus containing polymers in cold plasma in order to obtain flame-retardant materials. Cell. Chem. Technol., 14 869-883. 

The catalyst systems employed are based on molybdenum and phosphorus. They also contain Various additives (oxides of bismuth, antimony, thorium, chromium, copper, zirconium, etc.) and occur in the form of complex phosphomolybdates, or preferably heteropolyacids deposited on an inert support (silicon carbide, a-alumina, diatomaceous earths, titanium dioxide, etc.). This makes them quite different from the catalysts used to produce acrylic acid, which do not offer sufficient activity in this case. With residence times of 2 to 5 s, once-through conversion is better than 90 to 95 per cent, and the molar yield of methacrylic acid is up to 85 to 90 per cent The main by-products formed are acetic add, acetone, acrylic add, CO, C02, etc. The major developments in this area were conducted by Asahi Glass, Daicel, Japan Catalytic Chemical, Japanese Gem, Mitsubishi Rayon, Nippon Kayaku, Standard Oil, Sumitomo Chemical, Toyo Soda, Ube, etc. A number of liquid phase processes, operating at about 30°C, in die presence of a catalyst based on silver or cobalt in alkaline medium, have been developed by ARCO (Atlantic Richfield Co,), Asahi, Sumitomo, Union Carbide, etc. 

USk In the manuf of rayon, carbon tetrachloride, xantho-gosles, soil disinfectants, electronic vacuum tubes. Solvent for phosphorus, sulfur, selenium, bromine, iodine, fats, result, rubbers. 

OTHER COMMENTS used in the manufacture of rayon, carbon tetrachloride, soil disinfectants, and electronic vacuum tubes used as a solvent for phosphorus, selenium, sulfur, bromine, and iodine. 

Flame-Retardant Finishes on Cellulosic Substrates. The flame retarding of cotton and viscose-rayon fabrics has been the object of a large worldwide effort on phosphorus-containing finishes (217-219). The commercial cotton finishes are based on tetrakis(hydroxymethyl)phosphonium salts, usually the chloride or sulfate (220). These salts are prepared by reaction of formaldehyde with phosphine in the presence of an acid. 

C—S 155.3 pm. Has disinfectant and insecticidal props. used in manuf. of rayon and CCI4, electronic vacuum tubes, org. solv. for sulfur, phosphorus, iodine, bromine, rubber intermediates, etc. Fumigation insecticide. 

Carbon disulfide is a highly flammable, volatile liquid that acts as a solvent for sulfur, phosphorus, bromine, iodine, fats, and oils. Its uses as a solvent are decreasing, however, because CS2 is poisonous. Other important uses are in the manufacture of rayon and cellophane. 

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