Acrylic fibers flammability

Acrylic fiber breaking strength ranges between 22,000 and 39,000 psi and they have a water absorption of approximately 5%. Dynel, due to the presence of chlorine, is less flammable than many other synthetic fibers. 

Synonyms and trade names cyanoethylene, 2-propenenitrile, vinyl cyanide Use and exposure Acrylonitrile is a colorless, man-made liquid with a sharp, onion- or garlic-like odor. It can be dissolved in water and evaporates quickly. Acrylonitrile is used principally as a monomer in the manufacture of synthetic polymers, polyacrylonitriles, acrylic fibers, and other chemicals such as plastics and synthetic rubber. A mixture of acrylonitrile and carbon tetrachloride was used as a pesticide in the past. - Acrylonitrile is highly flammable and toxic. It undergoes explosive polymerization. The... 

Another property used to compare the flammability of textile fibers is the limiting oxygen index (LOI). This measurement quantity describes the minimum oxygen content (%) in nitrogen necessary to sustain candle-like burning. Values of LOI, considered a measure of the intrinsic flammability of a fiber, are listed in Table 12.28 in order of decreasing flammability. Acrylic fibers, it can be seen, are similar in flammability to cotton. Modacrylics, on the other hand, are somewhat less flammable than any of the synthetics, except 100% PVC, and are substantially less flammable than cotton and wool. 

The methods that have been used to enhance the flame resistance of acrylic and mod-acrylic fibers have been reviewed by Nametz [550]. Numerous reviews of flammability have been published [551-560], including the extensive work of Lewin et al. [378,379]. 

Hazardous Decomp. Prods. On decomp., emits toxic fumes of NO, NEPA Health 1, Flammability 2, Reactivity 0 Storage Store In cool, dry, well-ventilated area, out of direct sunlight Uses Solvent for llqs., gases. In vinyl resins, acetylene, butadiene, acid gases, paints, paint strippers, cleaners, zinc electroplating, acrylic fiber spinning, pharmaceuticals mfg. of polyacrylic fibers, butadiene. 

NFPA Health 2, Flammability 0, Reactivity 1 Uses Reactive flame retardant for acrylic fibers, PVAc, PVC in textiles, adhesives, coatings, photographic plates comonomer in prod, of acrylic fibers pharmaceutical intermediate Reguiatory HAP Manuf./Distiib. Akor Albemarle http //www.aibemarie.com-, Aldrich ht //www.sigma-aidrich.com-. King s Lab Trade Name Synonyms Saytex VBR t[Albemarle http //www.aibemarie.com]... 

Nytril fibers are made up of polymers containing at least 85% vinyli-dene dinitrile units, which appear at least every other unit in the polymer chain. The comonomer used in Nytril synthesis is vinyl acetate. The two monomers are polymerized in benzene using peroxide catalyst. The polymer is precipitated, washed, and dissolved in ], ] -dimethyl formamide and then passed through a spinneret into an aqueous coagulating bath to form Nytril fibers. The properties of the Nytril fiber are similar to the other acrylic fibers. The fiber possesses moderate tensile, regain, and thermal properties. The fiber is chemical and sunlight resistant but is as flammable as cellulosic fibers. Darvan Nytril fibers were produced in the U.S. until 1961. 

Acrylonitrile resembles VC, a carcinogen, in structure. It is a flammable, explosive liquid (b.p. 77 C, V.P. 80 mm at 20°C). AN is a component of acrylic and modacrylic fibers produced by copolymerization with other monomers, e.g., with methyl acrylate, Me-methacrylate, vinyl acetate, VC and VDC. Other major uses of AN include copolymerizations with butadiene and styrene to produce ABS polymers, and with styrene to yield SAN resins which are used in the manufacture of plastics. Nitrile elastomers and latexes are also made with AN, as are a number of other chemicals, e.g. acrylamide and adiponitrile. Acrylonitrile is also used as a fumigant. 

Hazardous Decomp. Prods. CO, CO2, NO, hydrogen cyanide NFPA Flealth 4, Flammability 3, Reactivity 2 Uses Monomer for acrylic and modacrylic fibers, paints in prod, of ABS and SAN copolymers, nitrile rubber, surfactants, adhesives, polyols, barrier resins, carbon fibers organic synthesis formerly as pesticide fumigant... 

Hazardous Decomp. Prods. Heated to decomp., emits toxic fumes of NOx NFPA Health 2, Flammability 2, Reactivity 0 Uses Solvent for plastics (vinyl, acrylic, cellulose, polyimide processing), resins, gums, fibers, coatings, adhesives, electrolytes, pharmaceuticals selective solvent for butadiene extraction reagent intermediate catalyst paint remover high-purity solvent for crystallization and purification reaction medium for prod, of pharmaceuticals, plasticizers... 

There have been reviews of flammability (70-74), methods that can be used to enhance the flame resistance of acrylic and modacrylic fibers (75), and the mechanism of flame-retardant additives (76). 

Flammability of PP becomes particularly critical in fibers, where solid additives may interfere with spinning and mechanical properties. A wide variety of flame retardants are therefore explored for such applications [35], often as coatings rather than additives. For example, addition of a liquid containing 45% Br+ 15% Cl, to polyvinyl acetate or acrylic latex, produces a flame retardant backing for PP fabrics, for applications such as upholstery [18]. 

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