Nonwoven fabrics applications

Other performances in relation to nonwoven fabric applications are also defined in EDANA/EMDA, ISO, and ASTM standards. Some examples are as follows ... 

The main applications for PVA are in textile sizing, adhesives, polymerization stabilizers, paper coating, poly(vinyl butyial), and PVA fibers. In terms of percentage, and omitting the production of PVA not isolated prior to conversion into poly(vinyl butyral), the principal applications are textile sizes, at 30% adhesives, including use as a protective colloid, at 25% fibers, at 15% paper sizes, at 15%, poly(vinyl butyral), at 10% and others, at 5%, which include water-soluble films, nonwoven fabric binders, thickeners, slow-release binders for fertilizer, photoprinting plates, sponges for cosmetic, and health care applications. 

Vinylidene Chloride Copolymer Latex. Vinylidene chloride polymers are often made in emulsion, but usually are isolated, dried, and used as conventional resins. Stable latices have been prepared and can be used diiecdy for coatings (171—176). The principal applications for these materials are as barrier coatings on paper products and, more recently, on plastic films. The heat-seal characteristics of VDC copolymer coatings are equally valuable in many applications. They are also used as binders for paints and nonwoven fabrics (177). The use of special VDC copolymer latices for barrier laminating adhesives is growing, and the use of vinylidene chloride copolymers in flame-resistant carpet backing is well known (178—181). VDC latices can also be used to coat polyethylene terephthalate) (PET) bottles to retain carbon dioxide (182). 

Polymers based on acrylic acid are highly hydrophilic and are utilized in different applications that include superadsorbent materials, flocculants and dispersants. Polyacrylates and their copolymers range from soft and flexible materials to hard plastics, applied in the production of coatings, paints, binders and adhesives. Their applications include the manufacture of cars e.g., coatings, upholsteries and adhesives) and the textile e.g., binders for fiberfill and nonwoven fabrics), paper and leather industries. Methyl acrylate is mainly utilized for copolymerization with acrylonitrile to improve the dyeability of fibres. 

Tubular Tubular membranes (Fig. 22-51) are supported by a pressure vessel, usually perforated or porous. It can be as simple as a wrapped nonwoven fabric, or as robust as a stainless-steel tnbe. All run with tnbe-side feed. They are mainly used for UF, with some RO applications, particularly for food and dairy. The primary diameters available are 12 and 25 mm. Tubes are often connected in series parallel bundles, gasketed or potted, are also common. 

Latex copolymers including NIBA have found applications in protective coatings, binders for nonwoven fabrics, water and oil repellancy, crease resistance, print pastes, leather finishing, adhesives, paper impregnation, curable thickeners and elastomers. (2B). Comonomers include acrylic and methacrylic esters, acrylo nTtrile, styrene, and occasionally vinyl acetate or vinyl chlorida... 

Use Nonwoven fabrics (short staple), woven fabric structures, cordage, thermal insulation, repair of furnace linings, piping molten metals, welding insulation (reusable), insulation for rocket and space applications. Note In finely divided form, alumina-silica is also used as a catalyst. 

Many industrial free-radical polymerization processes have been developed and commercialized for a variety of monomer and polymer types. A variety of monomers and polymerization processes have been commercially exploited. Further, there have been significant developments in synthesizing polymers with controlled architectures using free-radical polymerization during the last two decades. Materials synthesized include block copolymers, graft copolymers, and radial polymers. These materials find use in many common industrial and household applications such as adhesives, paints and coatings, textiles, nonwoven fabrics, personal care products, wallpaper, construction materials, specialty additives, and many other areas. 

INDA, the Association of the Nonwoven Fabrics Industry, has published repellency test methods specifically designed for the nonwoven fabric structure. 1ST 80.5(01/ is designed to measure a nonwoven material s abihty to resist gravity-only penetration by a saline solution. This property is useful in assessing the degree of water repeUency needed by nonwovens in a number of applications. A sample of the nonwoven to be tested is placed in the mouth of a quart size Mason jar containing saline solution. The jar is then inverted and placed on an electric grid that senses when the solution has penetrated the nonwoven. The time to complete penetration is recorded as a measure of repellency. 

Coated and laminated textiles usually consist of a textile substrate, which will typically be a woven, knitted or nonwoven fabric, combined with a thin, flexible fdm composed of a natural or synthetic polymeric substance. A coated fabric is one in which the textile substrate has a polymer film applied directly to one or both surfaces as a viscous liquid in a solvent or water, the thickness of which is controlled by application via a blade or similar aperture. A transfer coated fabric is an intermediate product in which a thermoplastic film is first prepared on a release paper prior to thermally bonding to the textile substrate. A laminated fabric usually consists of one or more textile substrates that are combined with a pre-prepared polymer film or membrane by adhesives or heat and pressure (Hall, 2000). 

Once again, for further reading the book Nonwoven Fabrics - Raw Materials, Manufacture, Applications, Characteristics, Testing Processes [B.107] is recommended. 

Various forms of chitin-based products are available for medical applications, such as finely divided powder, nonwoven fabrics, porous beads, lyophilized soft fleeces or gels, gauges, laminated sheets, and transparent films. Water-soluble derivatives of chitin in isotonic saline can be administered intramuscularly or intravenously. Certainly, there is considerable biochemical evidence linking NAG with the metabolism of the hexamines, which are assumed to originate and cross-link wound collagen. 

Ohshima, Y., Nishino, K., Yonekura, Y., Kishimoto, S., Wakabayashi, S., 1987. Clinical application of chitin nonwoven fabric as wound dressing. European Journal of Plastic Surgery 10, 66—69. 

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