Man-made fibers manufacture

For the purpose of discussion of the chemistry and technology of man-made, fiber-forming polymers, the term "synthetic fiber" will be used to denote all man-made fibers manufactured from noncellulosic raw materials. The term "cellulosics" will apply to those man-made fibers that are manufactured from cellulosic raw materials. The term "man-made fibers" will apply to all fibers except the naturally occurring cellulosic and protein fibers. 

Figure 14.22.2. Schematic diagram of emissions from the man-made fiber manufacturing industry. [Reproduced from EPA Office of Compliance Sector Notebook Project. Profile of the Petroleum Refining Industry. US...

The filter medium can be fibrous, such as cloth granular, such as sand a rigid solid, such as a screen or a mat, such as a felt pad. It can be in the shape of a tube, sheet, bed, fluidized bed, or any other desired form. The material can be natural or man-made fibers, granules, cloth, felt, paper, metal, ceramic, glass, or plastic. It is not surprising that filters are manufactured in an infinite variety of types, sizes, shapes, and materials. 

Conservation of Textiles Manufactured from Man-Made Fibers... 

The first man-made fibers of commercial importance were the cellu-losics. With respect to regenerated cellulose fibers, viscose rayon predominates. Between 1900 and 1967, world production of viscose rayon rose from 1000 tons to 2,700,000 tons (3). Cellulose derivative fibers did not go into commercial production until the 1920s. At that time cellulose acetate was manufactured. Cellulose triacetate fiber was brought into commercial production in the United States in 1954 (4). 

Modification of the polymer or the presence of additives can effect the light resistance of a fiber. This is extremely important for textile conservation since fibers being produced currently by the man-made fiber industry may perform differently from those produced in earlier years. For example, a company bulletin, published first in 1960, reported that the resistance to chemical decomposition by fluorescent light or by sunlight of many of the nylons they manufactured had been improved (20). Titanium dioxide, which is used as a delustrant during the manufacture of fibers, can decrease their light resistance (13,15,18, 21, 22, 23). Dyes (18, 24, 25) and finishes (25, 26) are other important factors. 

The searcher who dips into the literature of man-made fibers finds himself faced with a young but sprawling field. The sharply increased production of man-made fibers in the past few decades has been accompanied by a widening range of interests on the part of the fiber manufacturer. His activities have spread from the raw material sources, through fiber manufacture, then to textile processing, and finally to the end use of the textile material itself. 

The manufacture of all man-made fibers involves at least three distinct process steps. The first consists of the production of polymers or polymer derivatives suitable for spinning into fibers. In the second step, or spinning, a polymer melt or solution is extruded under pressure through the appropriate spinneret s orifice(s) to form the fiber or fibers. If only a single fiber is produced from a spinneret, it is referred to as monofilament. Multifilament spinnerets produce yarns. The third step is drawing,... 

Tables 14.22.1 and 14.22.2 provide data on releases and transfers from both polymer manufaeturing and man-made fiber produetion in flie USA. Carbon disulfide, methanol, xylene, and ethylene glycol are used in the largest quantities. Carbon disulfide is used in manufacture of regenerated cellulose and rayon. Efliylene glycol is used in the manufacture of polyethylene terephthalate, the manufacture of aUcyd resins, and as cosolvent for cellulose ethers and esters. Methanol is used in several processes, the largest being in the production of polyester. This industry is the 10th largest contributor of VOC and 7th largest in releases and transfers.

The man-made fiber industry provides models for high-rate manufacturing processes. 

With the industrial revolution came new discoveries and the development of the manufactured fibers industry, which was able to produce more new fibers than could be obtained from nature. The use of medical textiles derived from natural and man-made fibers as drug carriers increased dramatically, mainly in the form of bandages, therapeutic textiles, healthcare textiles, wound dressings, surgical operative sutures, transdermal patches for dermatosis and also for specific diseases. 

Plastics. Journal for the manufacture and application of processed or chemically fabricated materials with special consideration of artificial silk and other man-made fibers, of vulcanized, devulcanized (reclaimed) and synthetic caoutchouc, guttapercha etc. as well as substitute materials, of celluloid and similar cellulose products, of man-made leather and leather fabrics (linoleum), of resins, casein products etc. 

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