Olefin fibers

Olefin-CO coploymers Olefin p-complexes Olefin Fibers Olefin hydroformylation Olefin hydrogenation Olefimc alcohols Olefin isomerization Olefin metathesis Olefin oligomers Olefin oxides... 

Olefin fibers, also called polyolefin fibers, are defined as manufactured fibers in which the fiber-forming substance is a synthetic polymer of at least 85 wt % ethylene, propjiene, or other olefin units (1). Several olefin polymers are capable of forming fibers, but only polypropylene [9003-07-0] (PP) and, to a much lesser extent, polyethylene [9002-88-4] (PE) are of practical importance. Olefin polymers are hydrophobic and resistant to most solvents. These properties impart resistance to staining, but cause the polymers to be essentially undyeable in an unmodified form. 

Physical Properties. Table 1 (2) shows that olefin fibers differ from other synthetic fibers in two important respects (/) olefin fibers have very low moisture absorption and thus excellent stain resistance and almost equal wet and dry properties, and (2) the low density of olefin fibers allows a much lighter weight product at a specified size or coverage. Thus one kilogram of polypropylene fiber can produce a fabric, carpet, etc, with much more fiber per unit area than a kilogram of most other fibers. 

Fig. 6. Linear density of olefin fibers in various appHcations (29) dtex = 1.1 den.

Texturing. The final step in olefin fiber production is texturing the method depends primarily on the appHcation. For carpet and upholstery, the fiber is usually bulked, a procedure in which fiber is deformed by hot air or steam jet turbulence in a no22le and deposited on a moving screen to cool. The fiber takes on a three-dimensional crimp that aids in developing bulk and coverage in the final fabric. Stuffer box crimping, a process in which heated tow is overfed into a restricted oudet box, imparts a two-dimensional sawtooth crimp commonly found in olefin staple used in carded nonwovens and upholstery yams. 

Slit-Film Fiber. A substantial volume of olefin fiber is produced by slit-film or film-to-fiber technology (29). For producing filaments with high linear density, above 0.7 tex (6.6 den), the production economics ate more favorable than monofilament spinning (29). The fibers are used primarily for carpet backing and rope or cordage appHcations. The processes used to make slit-film fibers are versatile and economical. 

Pulp-like olefin fibers are produced by a high pressure spurting process developed by Hercules Inc. and Solvay, Inc. Polypropylene or polyethylene is dissolved in volatile solvents at high temperature and pressure. After the solution is released, the solvent is volatilised, and the polymer expands into a highly fluffed, pulp-like product. Additives are included to modify the surface characteristics of the pulp. Uses include felted fabrics, substitution in whole or in part for wood pulp in papermaking, and replacement of asbestos in reinforcing appHcations (56). 

Fig. 16. U.S. olefin fiber annual production +, staple plus tow I, yam plus monofilament <), total (71,72).

Olefin fibers are used for a variety of purposes from home furnishings to industrial appHcations. These include carpets, upholstery, drapery, rope, geotextiles (qv), and both disposable and nondisposable nonwovens. Fiber mechanical properties, relative chemical inertness, low moisture absorption, and low density contribute to desirable product properties. Table 7 gives a breakdown of olefin fiber consumption by use (73—75). Olefin fiber use in apparel... 

Table 7. Annual Domestic Shipments of Olefin Fibers, 10 t...

Olefin fiber is an important material for nonwovens (77). The geotextile market is stiU small, despite expectations that polypropylene is to be the principal fiber in such appHcations. Disposable nonwoven appHcations include hygienic coverstock, sanitary wipes, and medical roU goods. The two competing processes for the coverstock market are thermal-bonded carded staple and spunbond, both of which have displaced latex-bonded polyester because of improved strength, softness, and inertness. 

A special use for meltblown olefin fiber is in filtration media such as surgical masks and industrial filters (78). The high surface area of these ultrafine filament fibers permits preparation of nonwoven filters with effective pore sizes as small as 0.5 p.m. 

L. M. LandoU, "Olefin Fibers," iuj. I. Kroschwitz, ed., Enjclopedia of Poljmer Science and Engineering, 2nd ed., Vol. 10, John Wiley Sons, Inc., New York,... 

China. See also People s Republic of China acrylic fiber production in, 11.T89, 220 adhesive joint ventures, 1 526 advanced materials research, 1 696 aquaculture history, 3 183 aquaculture production, 3 189t ascorbic acid synthesis in, 25 754 demand for oil in, 23 530 nanocomposite development, 1 717 natural graphite in, 12 780 oil recovery program in, 23 534 olefin fiber production in, 11 243 production and consumption of regenerated cellulose fibers in,... 

Elastic recovery, 19 744 in olefin fibers, 11 227—228 Elastic scattering, 24 88-89 Elastic springs, in virtual two-way SMA devices, 22 346-347 Elastic waves, 17 422 Elastohydrodynamic (EHD) lubrication regime, 15 211-212 Elastomer-coated dies, in bar soap manufacture, 22 752 Elastomer designations, ASTM, 9 552t Elastomeric fibers, dyeing, 9 204 Elastomeric polycarboranylsiloxanes,... 

Elongated fullerenes, 12 232 Elongation, of olefin fibers, 11 226 Elongational rheometer, 21 740 Elongation at break, 10 177 19 743 Elongation viscosity, of olefin fibers, 11 233, 234... 

Fiber(s), 77 163-188. See also Acrylic fibers Carbon fibers Filled fibers High performance fibers New fibers Olefin fibers Optical fiber(s) Polyamide fibers Regenerated cellulose fibers Vegetable fibers antimicrobial acrylic, 77 215-219... 

Hard and soft acid and base (HSAB) principle, 16 780 Hard blacks, 21 775 Hard-burned quicklime, 15 28 Hard coals, 6 703 classification, 6 712 Hard copper alloys, 7 723t relief annealed, 7 723t Hard copy systems, 9 513-514 Hard core repulsion, 23 93 Hard-elastic olefin fibers, 11 242 Hardenability, of steel, 23 283—284 Hardened MF resins, analysis of,... 

Olefin fiber production, economic aspects of, 11 242-243 Olefin fibers, 11 224-246 applications of, 11 243-244 creep, stress relaxation, and elastic recovery in, 11 227-228 extrusion of, 11 231-234 hard-elastic, 11 242 high-strength, 11 241-242 manufacture and processing of,... 

Oxidative damage, role of ascorbic acid in preventing, 25 769 Oxidative degradation, 70 682 of gasoline, 72 399-400 Oxidative dehydrogenation, 23 342-343 Oxidative pyrolysis, 27 466 Oxidative stability, of olefin fibers, 77 229 Oxidative stability test, 72 400 Oxide crystal glass-ceramics, 72 641 Oxide-dispersion-strengthened alloys, 77 103-104... 

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