Fiber and Monofilament

Many evaluations have led to the commercial utilization of PEN, its copolyesters and blends in some commercial applications. The cost effectiveness is especially apparent in retumable-refillable applications, which take advantage of PEN s chemical resistance in commercial washing operations, so ensuring an increased number of re-fill trips [26], Other applications benefit from PEN s increased gaseous barrier, UV absorption, thinner and lower weight potential. Considerable effort is underway to enable utilization of PEN, its copolyesters and blends for beer, higher hot-fill and heat-pasteurizable containers [27], 

as for films, careful consideration of the optimal stretch ratios with or without heat setting of the naphthalate composition is essential to ensure cost effectiveness in a specific container. In the absence of this optimization, performance may be inferior to properly designed containers from the much less costly PET resin. 

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PBT is easily made into fiber and monofilament and has been used in some fiber applications. For example, PBT fibers are used commercially as toothbrush bristles. Compared to PET, PBT fiber is more resistant to permanent deformation. Compared to nylon, PBT shows almost no change when exposed to moisture. PBT shows much more resistance to staining than nylon and can be colored by the use of pigments. However, PBT is more difficult to color by solution dying than nylon. PBT is not typically used in textile applications due to its perceived high price. 

Papermarker s felt n. Formerly, a heavy, wide, coarse, worsted, or woolen fabric that was threaded between the rolls of the papermaking machine to form an endless conveyer belt for pulp or wet paper in its passage through the machine. These products are now also made of various constructions, woven, and non-woven, of manufactured fibers and monofilaments. 

The crystalline structure of PBT, studied by wide-angle x-ray scattering (WAXS), is characterized by a triclinic elementary cell. Two reversible triclinic modifications are possible an a- and a P-form [65]. The transition between the two modifications occurs reversibly by mechanical deformations from the a-form to the P-form by elongation and inversely by relaxation. The primary modification is the a-form with unit cell parameters a = 4.83 A, b = 94 A, c (fiber axis) = 11.59 A, a = 99.7°, P = 115.2°, and y = 110.8°, while the parameters for the unit cell of the P-form are a = 4.95 A, b = 5.67 A, c (fiber axis) = 12.95 A, a = 101.7°, P = 121.8°, and y = 99.9°. The unit cell is occupied by one repeating unit. As a result of reversible transitions in PBT, oriented fibers and monofilaments have outstanding release and toughness, which are important and useful characteristics for applications such as tooth- and paintbrush bristles and filler fabrics [17]. 

Fig. 1. Schematic drawings of five types of geotextile fibers (a) monofilament, (b) multifilament, (c) staple fibers, (d) staple yam, and (e) sHt film.

Surgical sutures are sterile, flexible strands used to close wounds or to tie off tubular structures such as blood vessels. Made of natural or synthetic fiber and usually attached to a needle, they are available ia monofilament or multifilament forms. Sutures are classified by the United States Pharmacopeia (USP) (1) as either absorbable or nonabsorbable. The USP also categorizes sutures according to size (diameter) and Hsts certain performance requirements. Sutures are regulated by the Food and Dmg Administration (FDA) as medical devices under the Food, Dmg, and Cosmetics (FDC) Act of 1938, the Medical Device Act of 1976, and the Medical Device Reporting regulation of 1995. 

The B. mori silk fiber is made up of two kinds of protein. One is called sericin, a water-soluble protein responsible for the gum-like, sticky coating covering the fiber, and the other is referred to as fibroin, the core filament of silk. The inner part of silk fiber is composed of two monofilaments called brins (Figure la) (Poza et al., 2002 Shao and Vollrath, 2002). 

In 2000 nylon-6 fibers (including monofilament) consumed 74% of the caprolactam for textile, industrial (i.e., tire cords, seat belts, and fishing line) and carpet yams. Engineering resins and film consumed the other 26% of the production265 267. 

Yarn and monofilament only staple plus tow included under other. c Does not include fiber produced for cigarette filtration purposes. d Includes saran and Spandex yarn also, olefin and vinyon staple and tow. 

Available forms Extrusion and molding powder, aqueous dispersion, film, monofilament fiber, and nonsticking finish. 

Teflon [Du Pont], TM for tetrafluoroethyl-ene (TFE) fluorocarbon polymers available as molding and extrusion powders, aqueous dispersion, film, finishes, and multifilament yam or fiber. The name also applies to fluorinated ethylene-propylene (FEP) resins available in the same forms. The no-stick cookware finishes may be of either type. Fibers are monofilaments made from copolymer of TFE and FEP. 

Commercial PP/EPDM blends (Modylen ) have been routinely spun. The PP matrix contains EPDM as impact modifier, a filler and an interfacial additive. The compositions can be spun into fibers and yams and extruded into monofilaments. 

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