Textile fibers melt spinning

Synthetic Fiber and Plastics Industries. In the synthetic fibers and plastics industries, the substrate itself serves as the solvent, and the whitener is not appHed from solutions as in textiles. Table 6 Hsts the types of FWAs used in the synthetic fibers and plastic industries. In the case of synthetic fibers, such as polyamide and polyester produced by the melt-spinning process, FWAs can be added at the start or during the course of polymerization or polycondensation. However, FWAs can also be powdered onto the polymer chips prior to spinning. The above types of appHcation place severe thermal and chemical demands on FWAs. They must not interfere with the polymerization reaction and must remain stable under spinning conditions. 

Early in the manufacture of PP, a concept was developed for dry spinning directly from the solution obtained in the polymerization operation. Had it been feasible, it would have been the realization of a chemical engineer s dream the gaseous olefin fed into one end of the equipment, and the packaged fiber, ready for shipment to a textile mill, coming out the other end. But it did not turn out that way, and today melt spinning is the accepted technique for the production of staple fibers, monofilament, and multifilament yams. To this usual method have been added the fibrillation and the slit film procedures for producing yams. 

Nylon. In 1939 the DuPont Company introduced the first truly synthetic textile fiber. Dr. Wallace Carothers invented nylon as a result of his basic research into polymer science. Chemically, nylon is a polyamide fiber. The two major types of nylon polymer are used in textiles type 6,6 which is made by using hexam-ethylene glycol and adipic acid, and type 6, which is made by polymerizing e-caprolactam. Nylon fibers are made by melt-spinning the molten polymer. The result is a continuous filament fiber of indeterminate length. It is spun in many deniers, with its diameter varying from 10 to 50 microns. The cross-section usually is round, trilobal, or square with hollow channels when used as carpet fiber. 

Vinyl polymers and condensation polymers were studied for the production of synthetic fiber. In 1932, Carothers and Hill of Du Pont studied linear aliphatic polyester and showed that fibers of sufficiently good mechanical properties are obtained by melt-spinning and colddrawing [8]. Polyester fiber was considered unsuitable as a commercial fiber because it has a low melting point and hydrolyzes easily with water. Carothers therefore turned his investigation from polyester to polyamide, and, in 1938, Du Pont announced the success of a new fiber called nylon. In Japan, studies to produce textile fibers from PVA began in 1938 and were intensively promoted. 

The poly (olefin) fibers are manufactured in the largest volumes thanks to the low cost of the polymers and the simple melt-spinning production technology. Annual worldwide production of textile products based on poly(olefins) was 1.7 10 t/a in 1985, 90 % of which was isotactic poly(propylene) PP and 10 % high-density poly(ethylene) HOPE [81]. ... 

Polyolefin textile fibers are usually produced through the melt spinning process with good mechanical properties and chemical and abrasion resistance. One of the main drawbacks in this industry is the fact that they are difficult to dye unless additives are used. One of the major applications of PP is the use in carpet which replaced natural fibers. Other apphcations include bags, sportswear, and knitwear. 

Fiber spinning process Melting spinning is the common process used to make textile-type polyolefin fibers (UHMWPE is an exception due to its ultra-high molecular weight as will be seen later). The process of making continuous filament yam consists of the following steps [2] ... 

The one step process for the fabrication of pure silica sliver from sodium silicate [1-3] is an adaptation oil the generic dry spinning process that has been practiced for over 50 years in the fabrication of polymer organic textile fibers. Acrylic polymers, unlike polyesters or nylons, are infusible and cannot be melt spun. They can be dry or wet spun from viscous solutions. The model for inorganic dry spinning processes is the dry spinning process by means of which acrylic fibers such as Orion, are spun using dimethyl formamide as the solvent (Table I). 

A special example of extmsion is fiber spinning (Fig. 3.3). Also called as melt spinning, this is widely used in the manufacture of textile fibers. But the operation... 

Keywords bulk continuous fibers (BCF), crystallinity, drawing, elasticity, elongation, fiber-forming polymer, fiber monofilament, low oriented yam (LOY), melt blown process, melting, monofilament, multifilament silk, orientation, partially oriented yam (POY), staple fibers, spinning, spunbonded fibers, stmcture, technical fiber, tenacity, textile fiber, texturing. 

All polymer electroconductive fibers can be obtained by blending ICPs with common polymers. At our in-house Smart Textile facilities we produced PP/PANI and PP/ PA/PANI composite fibers. Pig. 28.7. The production of these fibers involved two steps compounding and spinning. For fiber spinning, the melt spinning process is the most suitable method. The ICP-based electroconductive fibers we have produced... 

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