Fibers polyacrylonitrile

Highly colored, they have been used to dye cellulose acetate (552) and acrylic fibers (553). Cationic dyes prepared from 2-azothiazoles by simple alkylation on the ring nitrogen (552) have been used increasingly with the introduction of polyacrylonitrile fibers with basic sites that can be colored with such dyes (554). 

The (A/-alkylated) lactam of 8-aminonaphthalenecarboxylic acid (47) also is a valuable dye iatemiediate, eg, for cyclometbine-type dyes used for dyeiag polyacrylonitrile fibers and other synthetics. 1,8-Naphtholactams are prepared in high yield and purity by the reaction of naphtholactones with RNH2 (R = H, Cl—4 alkyl, cycloalkyl, or optionally substituted aryl) in aqueous medium, usually in the presence of bisulfite at 150°C over a period of 15 h (143). 

Statistics for the production of basic dyes include those products hsted as cationic dyes, eg, cyanines, for dyeing polyacrylonitrile fibers and the classical triaryhnethane dyes, eg, malachite green, for coloring paper and other office apphcations (2,53). Moreover, statistics for triaryhnethane dyes are also hidden in the production figures for acid, solvent, mordant, and food dyes, and also organic pigments. Between 1975 and 1984, the aimual production of basic dyes in the United States varied from 5000—7700 t. However, from 1985—1990, aimual production of basic dyes varied from 5000—5700 t, and the annual sales value increased from 56 to 73 million per year. 

W. Watt, "Chenhstry and Physics of the Conversion of Polyacrylonitrile Fibers into High Modulus Carbon Fibers," in Ref. 6. 

In the 1950s acid dyes were successively developed to dye nylon carpet with excellent fastness and uniform leveling. Development of polyacrylonitrile fiber stimulated the invention of anthraquinone basic dyes, modified disperse dyes in which quaternary ammonium groups are introduced. 

SPAN module. It was mentioned at the beginning that the special polyacrylonitrile fibers of SPAN have a wall thickness of 30 gm, which is considerably thicker than the 8 gm wall thickness of the SMC modules [19]. As a consequence, the presence of stronger capillary effects from the special porous fiber material of the SPAN module would be a reasonable conclusion. Furthermore, the texture of the special polyacrylonitrile fibers is expected to have better surface properties, supporting the permeation of molecules as compared with synthetically modified cellulose. In conclusion, both convection and diffusion effectively contribute to the filtration efficiency in a SPAN module, whereas for the SMC membrane, diffusion is the driving force for molecular exchange, the efficiency of which is also considerable and benefits from the large surface-to-volume ratio. 

Triphenylmethane leuco dyes are far more important than the diphenylmethanes in terms of practical value. Use of triphenylmethane dyes for traditional applications of dyes is limited to dyeing wool, silk, leather, and polyacrylonitrile fibers. The largest portion of the annual production of this class of leuco dyes is consumed in the manufacturing of various copying papers. 

Moafi et al. [143] studied the ability of titania versus zirconia to photocatalyze methylene blue and eosin yellow on polyacrylonitrile fibers. Ti02 particles ranging from 10-20 nm in size and Zr02 particles ranging from 20-40 nm in size were dispersed on the fiber surface. Photocatalytic activity of Ti02 was greater. 

Moafi, H.F., Shojaie, A.F. and Zanjanchi, M.A. (2010) The comparative study of photocatalytic self-deaning properties ofsynfhesized nanoscale titania and zirconia onto polyacrylonitrile fibers. Journal of Applied Polymer Science, 118, 2062-2070. 

Polyacrylonitrile fibers are used in making carpets and clothing. 

The created technology of producing cationic and anionic exchange fibroid sorbents on the base of polyacrylonitrilic fibers is described in the paper. Chemical characteristics of the sorbent and filters were investigated. The static exchange capacity is 3-4 meq/g for cationic sorbents and 1-2 meq/g for anionic sorbents. The removal coefficient of listed radionuclides from drinking water by the filter is 102 - 103. 

The produced cationic and anionic exchange fibroid sorbents on the base of polyacrylonitrilic fiber were used to produce household water filters. The cloths of cationic and anionic exchange sorbents with mass of 50 g each one were reeled on a perforated cylinder with diameter of 10 mm and length of 15 mm. This cartridge could be easily replaced. Initial tap water... 

Oxide-water interfaces, in silica polymer-metal ion solutions, 22 460—461 Oxidimetric method, 25 145 Oxidization devices, 10 77-96 catalytic oxidization, 10 78—96 thermal oxidation, 20 77-78 Oxidized mercury, 23 181 Oxidized polyacrylonitrile fiber (OPF), 23 384... 

Trade (and/or brand) names and abbreviations are often used to describe a particular material or a group of materials. They may be used to identify the product of a manufacturer, processor, or fabricator, and may be associated with a particular product or with a material or modified material, or a material grouping. Trade names are used to describe specific groups of materials that are produced by a specific company or under license of that company. Bakelite is the trade name given for the phenol-formaldehyde condensation developed by Baekeland. A sweater whose material is described as containing Orion contains polyacrylonitrile fibers that are protected under the Orion trademark and produced or licensed to be produced by the holder of the Orion trademark. Carina, Cobex, Dacovin,... 

Polyacrylonitrile fibers Block copolymers High-impact polystyrene (HIPS)... 

Feng YS, Chen PC, Wen FS et al (2008) Nitrile hydratase from Mesorhizobium sp F28 and its potential for nitrile biotransformation. Process Biochem 43 1391-1397 Wang CC, Lee CM, Wu AS (2009) Acrylic acid removal from synthetic wastewater and industrial wastewater using Ralstonia solanacearum and Acidovorax avenae isolated from a wastewater treatment system manufactured with polyacrylonitrile fiber. Water Sci Technol 60 3011-3016... 

In addition to the established large volume products already mentioned, other plastic materials are known to be under study or have been introduced so recently that their markets have not been fully developed. It seems certain that products such as polyethylene terephthalate and polyacrylonitrile fibers will attain large volume production. A new type of resin that has appeared very recently is Shell Chemical Co. s Epon series (32), a group of polymers of various molecular weight ranges which are produced from phenol, acetone, and epichlorohydrin. 

Stearamidomethylpyridinium chloride is used in waterproofing textiles. It is made by reacting pyridine hydrochloride with stearamide and formaldehyde. Vmylpyridines are used as components of acrylonitrile copolymers to improve the dyeability of polyacrylonitrile fibers. Tile commercially important products are 2-vinylpyndine 4-vinylpyndine and 2-methyl-5-vinylpyridine. Formulas are shown below. 

Tn the last decades many attempts have been made to obtain attractive - materials by intimate mixing of two polymers with opposite or complementary properties. For example, the impact resistance of brittle polystyrene is increased by mixing with a rubber the wettability of polyacrylonitrile fiber is increased by mixing with hydrophilic saponified cellulose acetate, and the inconvenient flat-spotting of nylon-reinforced tires is suppressed by mixing stiffer polyester fibrils into the nylon fibers. In practically all cases these products acquire their final shape via the liquid state. Thus, the viscous properties of these liquid mixtures are important. 

An example of this type is the enamine dye 6, which confers a yellow color to polyacrylonitrile fibers [3],... 

One or several of the carbon atoms in the chain may be replaced by nitrogen, as is indicated by the prefix aza. Depending on the number of nitrogen atoms introduced into the chain, mono-or diazadimethine dyes are obtained. Tri- and tetraazamethine dyes are also known. An example is dye 11, which gives polyacrylonitrile fibers a golden yellow color [7],... 

Cationic dyes are also used to dye polyacrylonitrile fibers during the spinning process either from dimethylformamide solution or in the gel stage subsequent to aqueous spinning processes. 

The three major dye types, i.e., neutral, anionic, and cationic, are subdivided by use the neutral dyes comprise disperse, vat, and solvent dyes the anionic dyes, acid, direct, and reactive dyes and the cationic dyes, dyes for polyacrylonitrile fibers and other fibers modified to contain acid groups. 

When polyacrylonitrile fibers appeared on the market, an intense research effort in the area of cationic azo dyes was stimulated worldwide at all the leading dye plants. These materials now occupy a place of importance in all significant product lines. 

Polyamines as Coupling Components. Chrysoidines are obtained by coupling dia-zonium salts of aniline, toluidines, or mixtures thereof to polyamine coupling components such as 1,3-phenylenediamine, 2,4- or 2,6- toluylenediamine, or mixtures of these diamines. These dyes confer muted yellow to orange shades to paper, leather, and polyacrylonitrile fibers. When they are mixed with malachite green and fuchsin, medium-fast black shades are obtained on polyacrylonitriles. A mixture of chrysoidine with Crystal Violet or Victoria Pure Blue is used to adjust the color of nigrosine hectograph inks [1]. 

If A-amino nitrogen heterocycles are used as the hydrazine component, cyclic hydrazone dyes are obtained whose absorption maximum is shifted bathochromi-cally with respect to the open-chain hydrazone dyes [38], The dye 15 dyes polyacrylonitrile fibers a clear bluish red shade ... 

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