Cotton fiber precursors

The cotton fiber does not contribute anything that causes hazardous air emissions from textile operations processing cotton [9,47]. Cotton production and ginning can be sources of particulate matter (PM) emissions that are regulated by the U.S. EPA. Neither is a major source under EPA regulations. Cotton production can also be a minor source of volatile organic chemicals that are precursors of ozone and of oxides of nitrogen. 

Cotton fibers have been coated with silicone dioxide-based layers using atmospheric pressure plasma (APP) technique. SiO network armor was obtained through hydrolysis and condensation of the precursor TEOS and has been cross linked on the surface of cotton fibers. Because of the protective effects of the SiO network armor, the modified cellulosic fibers exhibit improved flame retardancy. SiO -APP coated textiles may have in the future numerous applications in the development of upholstered furniture, clothing, and military (Totolin et al., 2010). 

Phloroglucinol is Hsted in the Colourindex as Cl Developer 19. It is particularly valuable in the dyeing of acetate fiber but also has been used as a coupler for azoic colors in viscose, Odon, cotton (qv), rayon, or nylon fibers, or in union fabrics containing these fibers (157). For example, cellulose acetate fabric is treated with an aromatic amine such as (9-dianisidine or a disperse dye such as A-hydroxyphenylazo-2-naphthylamine and the amine diazotizes on the fiber the fabric is then rinsed, freed of excess nitrite, and the azo color is developed in a phloroglucinol bath at pH 5—7. Depending on the diazo precursor used, intense blue to jet-black shades can be obtained with excellent light-, bleach-, and mbfastness. 

Direct dyes are defined as anionic dyes substantive to ceUulosic fibers (cotton, viscose, etc), when applied from an aqueous bath containing an electrolyte. Before the discovery of Congo Red in 1884, only mordanted cotton could be dyed. Congo Red [573-58-0] (62) (Cl Direct Red 28 Cl 22120) a primary symmetrical disazo dye, which is made readily from bisdiazotized benzidine and naphthionic acid [84-86-6] (4-arnino-l-naphthalenesulfonic acid), was the precursor of a most important line of dyes, including all shades, derived from benzidine and its homologues. Today, no benzidine dye is produced because benzidine is carcinogenic. 

Carbon fiber electrode - Edison produced the first carbon fibers by carbonization of cotton threads in 1879. Today polyacrylonitrile (as well as Rayon and various other organic precursors) is the most common precursor for carbon fiber formation [i]. Carbonization of polyacrylonitrile is carried out at 1500 °C to give highly electrically conducting fibers with 5-10 pm diameter. Fibers carbonized at up to 2500 °C are more graphitic with a carbon content of >99%. Carbon fiber-based materials have found many applications due to their exceptionally high tensile strength. In electrochemistry carbon fiber -> micro electrodes are very important in analytical detection [ii] and for in vivo electrochemical studies [iii]. Carbon fiber textiles are employed in - carbon felt electrodes. 

The composition of such breakdown products is highly dependent on the precursor, the heating conditions and whether a catalyst is used or not. The term catalyst in this sense is a substance which has an influence on the actual cellulose pyrolysis process. Tamaru [66] investigated the effect of inorganic salts on the pyrolysis and combustion of cellulose. Garn and Denison [67] investigated flame retardants for cotton, which had a direct spin-off for carbon fiber manufacture. Typical treatment products/catalysts that have been investigated... 

Carbonization of rayon (and PAN) yams and fabrics was briefly Investigated by Union Carbide Corporation during World War II as a possible substitute material for control grids In vacuum tube power amplifiers [5]. However, the first conmerclal venture Into multifilament carbon fibers was about 1957 by Bamebey-Cheney, a licensee of W. F. Abbott s Carbon Wool Corporation, which briefly manufactured carbon fiber tows, mats, and batting materials from cotton and rayon precursors [6], These materials were developed for use as high temperature thermal Insulation, as particle filters for hot, corrosive gases or liquids and as activated carbon fibers. 

Cellulose. Celluloseisthemajorconstituentofwoodandotherplants. Cotton and rayon are almost pure cellulose and the latter is a precursor for carbon fibers. The pyrolysis of cellulose, like that of PAN, is reviewed in Ch. 8. 

Some metal oxide nanoparticles possess unique, significant applications when electrospun with certain polymers. Lee [76] successfully developed layered fabric systems with electrospun polyurethane/zinc oxide nanocomposite fiber webs layered on cotton substrates, which imparted UV protection and antibacterial functions. Okuyama et al. [77] used mixed solutions of indium tin oxide (ITO) nanoparticle sol and PEO as precursors of the nanofibers to prepare ITO nanofibers via... 

Many cellulose fibers, including both natural and manufactured cellulose fibers, can be made into carbon fibers by high temperature treatment. However, carbon fibers made from natural cellulose fibers, such as cotton and ramie, often have high defect contents, which limit the strength of the fibers. Currently, rayon, a manufactured cellulose fiber, is the most used cellulose-based carbon precursor. 

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