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Filament textile acrylics

Filament textile acrylics seem to have lost the competition with polyester and nylon. [Pg.952]

Most textile acrylics contain 10-15% comonomers. For carbon fiber precursors lower comonomer levels are used (about 5%) comonomers are selected that promote the reactions in the aftertreatment (methyl acrylate, itaconic acid). Wet spinning is preferred because the cross-section can be controlled better then. In dry spinning skin formation can hardly be prevented and eventually the cross-section collapses into a "dog bone shape, which is not desirable in carbon fiber applications. Precursor filaments are drawn to much higher draw ratios (> lOx) than tex-... [Pg.965]

High strength acrylic fibres have been developed with a modulus of elasticity in the range of 14-25 GPa, and tensile strengths up to 1000 MPa [124-126] that is, the modulus of elasticity is of the same order of magnitude as that of the matrix. The fibres can be produced in the form of discrete short filaments, and can also be woven into various fabrics. The stress-strain curves of these fibres are shown in Figure 10.35, where they are compared with conventional textile acrylic fibres. The increases in tensile strength and modulus of elasticity relative to the textile... [Pg.414]

Vinyon N is a continuous-filament yarn and Dynel is a staple fibre both are copolymers composed of 60 per cent vinyl chloride and 40 per cent acrylonitrile. These fibres are considerably more stable towards heat commencing to shrink at 116°C, and softening in the region of 130°C when shrinkage becomes marked. Dynel finds textile application because it has adequate stability towards heat, an extremely soft handle and is cheaper than the acrylics. [Pg.151]

Customer-recollected waste from fiber and textiles consists mainly of continuous filaments or staple fibers, which may be contaminated with dyestuffs, finishes and knitting oils, and other fibers such as cotton, wool, rayon, nylons, and acrylics they are the most diflScult-to-recover products. [Pg.715]

Metallized textiles are studied as a means to improve radar screens, making them more sensitive to small objects. The ability to be seen by radar is greatly increased by sheet-like materials containing thin layers of metallized fibers. Bayer has developed an acrylic filament yarn of 238 dtex, which gives radar reflectance of as much as 90%. The fiber is coated with a 0.02-2.5 pm layer of nickel by a currentless wet-chemical disposition process [684,685]. Other metallized fibers have been developed based on palladium [686]. [Pg.950]

Prepared filaments and fibres are applied not only in the floor coverings as the most important utilization for PP, but also medical, hygienic, apparel, automotive and/or agricultural sectors became crucial, for applications such as disposable diapers, sports underwear and equipment, artificial grass, geo textiles, ropes, car seats, oil wipes, wet and dry filters or membranes. Physical and chemical properties of polyolefins fibres are developed for many applications, in order to increase comfort characteristics, tensile strength, and/or other utility properties they are often blended, co-processed or combined with other materials such as polar acrylics, wool, bonding agents, hydrophilic fillers, or stabilizers. [Pg.102]

As stated above, conventional synthetic fibres may be rendered inherently flame retardant during production by either incorporation of a flame retardant additive in the polymer melt or solution prior to extrusion or by copolymeric modification before, during, or immediately after processing into filaments or staple fibres. Major problems of compatibility, especially at the high tanperatures used to extrude melt-extruded fibres like polyamide, polyester, and polypropylene and in reactive polymer solutions such as viscose dope and acrylic solutions, have ensured that only a few such fibres are commercially available. A major problem in developing successful inherently flame retardant fibres based on conventional fibre chemistries is that any modification, if present at a concentration much above 10wt% (whether as additive or comonomer), may seriously reduce tensile properties as well as the other desirable textile properties of dyeability, lustre and appearance, and handle, to mention but a few. [Pg.252]

Fibers are the basic element of nonwovens world consumption of fibers in nonwoven production is 63% polypropylene, 23% polyester, 8% viscose rayon, 2% acrylic, 1.5% polyamide and 3% other high performance fibers [8]. The data in Fig. 10.4 shows the market share of important polymers and fibers in the nonwovens market. Manufacturers of nonwoven products can make use of almost any kind of fibers. These include traditional textile fibers, as well as recently developed hi-tech fibers. Future advancements will be in bicomponent fibers, micro-fibers (split bicomponent fibers or meltblown nonwovens), nano-fibers, biodegradable fibers, super-absorbent fibers and high performance fibers. The selection of raw fibers, to a considerable degree, determines the properties of the final nonwoven products. The selection of fibers also depends on customer requirement, cost, processability, changes of properties because of web formation and consolidation. The fibers can be in the form of filament, staple fiber or even yam. [Pg.314]

Products based on the acrylonitrile copolymers used for standard acrylic textile fibres are of little importance in polymer matrices. Specialized polymers of higher, often 100%, acrylonitrile content are converted into continuous-filament and staple fibres for use in composites such as friction products. [Pg.555]

Lastly, synthetic varieties of textiles are present primarily in apparel and are either petroleum-based or blends with natural fibers. Polyester fibers, aramid fibers, acrylics, nylon, polyurethane, olefins (hydrophobic), polylactide (hydrophilic), milk protein-based fibers, and carbonization-based fibers all constitute synthetics which require some level of surface-modification. This includes nonwovens, structures bonded together by entangling fiber or filaments mechanically, thermally, or chemically. [Pg.109]


See other pages where Filament textile acrylics is mentioned: [Pg.939]    [Pg.285]    [Pg.612]    [Pg.444]    [Pg.500]    [Pg.36]    [Pg.284]    [Pg.36]    [Pg.913]    [Pg.914]    [Pg.932]    [Pg.945]    [Pg.950]    [Pg.261]    [Pg.101]    [Pg.21]    [Pg.399]    [Pg.169]    [Pg.116]    [Pg.506]    [Pg.1027]    [Pg.58]    [Pg.49]    [Pg.27]    [Pg.15]    [Pg.300]    [Pg.129]   
See also in sourсe #XX -- [ Pg.952 ]




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