Qiana

Several other polyamides have been introduced for use as fibers in specialty applications where certain combinations of properties are desired. The major specialty nylons include Qiana, nylon 4, nylon 11, nylon 6,10, and biconstituent nylon-polyester. Their particular characteristics are outlined below. 

Qiana is a trade name (duPont) for the luxury nylon fiber formed through step growth polymerization of trans.trans-di(4-aminocvclohexvn methane and a dibasic acid having 8-12 carbon atoms  

Qiana resembles nylon 6 and 6,6 in many of its properties but also has a unique silklike texture, a lustrous appearance, excellent form retention, and an overall superior performance level which makes it useful in prestige textile products and in the sophisticated fashion apparel market. 

Nylon II is produced by self-condensation of Il-aminoundecanoic acid in Europe and marketed under the name Rilsanite. It is melt spun (mp 189°C) into fiber and possesses essentially the same properties as nylon 6 and 6,6. It has high strength (5-7.5 g/d), low specific gravity (1.04), 

Nylon 6,10 is produced by condensation polymerization of hexamethylene diamine and sebacic acid and is melt spun (mp 216°C) into fibers. It resembles nylon 6 and 6,6 in many ways but has a lower moisture regain (2.6°A. It is primarily used in brush bristles. 

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Qiana, introduced by Du Pont in 1968 but later withdrawn from the market, was made from bis(4-aminocyclohexyl)methane and dodecanedioic acid. This diamine exists in several cis—trans and trans—trans isomeric forms that influence fiber properties such as shrinkage. The product offered silk-like hand and luster, dimensional stabiUty, and wrinkle resistance similar to polyester. The yam melted at 280°C, had a high wet glass-transition temperature of - 85° C and a density of 1.03 g/cm, the last was lower than that of nylon-6 and nylon-6,6. Qiana requited a carrier for effective dyeing (see Dye carriers). 

The polyamide copolymer of dodecanoic acid with methylenedi(cyclohexylamine) (MDCHA, PACM) was sold as continuous filament yam fiber under the tradename QIANA. As late as 1981, over 145,000 t was produced using high percentages, typically 80%, of trans, trans MDCHA isomer. The low melting raffinate coproduct left after t,t isomer separation by fractional crystallisation was phosgenated to produce a Hquid aUphatic diisocyanate marketed by Du Pont as Hylene W. Upon terrnination of their QIANA commitment, Du Pont sold the urethane intermediate product rights to Mobay, who now markets the 20% trans, trans—50% cis, trans—30% cis, cis diisocyanate isomer mixture as Desmodur W. In addition to its use in polyamides and as an isocyanate precursor, methylenedi (cyclohexyl amine) is used directiy as an epoxy curative. The Hquid diamine mixture identified historically as PACM-20 is marketed as AMICURE PACM by Anchor Chemical for performance epoxies. 

HMD was originally produced by Du Pont as a coproduct in the manufacture of Qiana fiber. Du Pont subsequently sold the product to Bayer. In the 1990s MDA is hydrogenated by Air Products for Bayer (see Amines, aromatic-methylenedianiline). Commercial HMDI is a mixture of three stereoisomers. Semicommercial aUphatic diisocyanates include /n j -cyclohexane-l,4-diisocyanate (CHDI) and y -tetramethylxylylene diisocyanate (TMXDI). A coproduct in the production of TMXDI is y -isopropenyl-a,a-dimethylben2yl isocyanate (TMI), which can be copolymerized with other olefins to give aUphatic polyisocyanates. 

One of the butadiene dimeri2ation products, COD, is commercially manufactured and used as an intermediate in a process called FEAST to produce linear a,C0-dienes (153). COD or cyclooctene [931-87-3], obtained from partial hydrogenation, is metathesi2ed with ethylene to produce 1,5-hexadiene [592-42-7] or 1,9-decadiene [1647-16-1], respectively. Many variations to make other diolefins have been demonstrated. Huls AG also metathesi2ed cyclooctene with itself to produce an elastomer useful in mbber blending (154). The cycHc cis,trans,trans-tn.en.e described above can be hydrogenated and oxidi2ed to manufacture dodecanedioic acid [693-23-2]. The product was used in the past for the production of the specialty nylon-6,12, Qiana (155,156). 

Qiaiia, a polyamide fiber with a silky texture, has the following structure. What are the monomer units used in the synthesis of Qiana ... 

Qiana, structure of, 836 Quantum mechanical model, 4-6 Quartet (NMR), 460 Quaternary ammonium salt. 917 Hofmann elimination and, 936-937... 

Qiana, a poiyamide that feeis much iike siik, has the foiiowing structure ... 

Visuaiize the condensation reaction that forms a poiymer. Two monomers with appropriate functionai groups combine, forming a new bond and eiiminating water. Reverse this process to see what monomers make Qiana. 

QEKIRVRLSA antimicrobial peptide, 26 799-800 Qiana, 19 764 QikProp, 6 18 Qinghai Lake, 5 784 Q parameter, impeller, 16 676 QSAR analysis, 10 327t, 328-329. See also Quantitative structure—activity relationship (QSAR) studies 3D QSAR models... 

Qiana W, Tana Y, Dinga S, Wanga Y (2008) A label-free biosensor based on gold nanoshell monolayers for monitoring biomolecular interactions in diluted whole blood. Biosens Bioelectron 23(7) 1166-1170... 

Qiana [Du Pont]. TM for a nylon-type synthetic fiber with properties similar to silk. 

A commercially important polyamide based on an alicyclic diamine is Qiana (Structure IV), which was introduced by Du Pont in 1968. 

It is produced by the melt condensation of dodecanoic acid and bis(4-aminocyclohexyl)methane. Many of Qiana s unusual properties, including its silklike feel and dyeability, result from the several isomeric forms of the diamine. The polymer is believed to be a mixture of the trans-trans and cis-trans diamine isomers in a ratio of approximately 4 1 (w w) (13). 

Printogen HD. [Sandoz] Weakly cationic glycol ethm carrier for superheated steaming of polyester and Qiana printed with disperse dyes. 

Research and development in fluid jet technology led to its widespread use in film and web processing, mixers, reactors, and fiber processing. Applications to fibers alone includes Taslan bulked yams, jet piddlers, draw-jets, interlaced yams, bulk-crimped carpet fibers (BCF), and spunbonded products such as Reemay polyester, Typar polypropylene (PP), and Tyvek olefins. New fibers also were introduced Nomex aramid, especially suited for high-temperature applications Lycra spandex, an elastic textile yam Qiana nylon, with a silklike appearance and Kevlar aramid, used in products ranging from tires to bullet-resistant vests. 

Yua, D., Sunb, X., Bianb, J., Tonga, Z., and Qiana, Y. 2004. Gamma-radiation synthesis, characterization and nonlinear optical properties of highly stable colloidal silver nanoparticles in suspension. Physica E 23 50-55. 

Polymers have also been prepared from cyclic amines such as piperazine and bis(p-aminocyclohex-yl) methane. The latter amine is condensed with decanedioic acid to produce the silklike fiber Qiana (Du Pont). 

Qiana fibers have a high glass transition temperature (135°C, as compared to 90"C for nylon-6,6), which assures that the polymer will remain in the glassy state during fabric laundering and resist wrinkles and creases. 

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