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Flammability/flame retardation

Polymer Structure and Flammability Flame Retardation of Polymers Synergism in Flame Retardation Selection of Fire Retardants Flame Retardation of Polymeric Materials... [Pg.305]

Because of the abundance of styrene, polystyrene can be cheaply produced and used in many commercial qiplications. However, polystyrene is brittle and this limits tlieir utility in applications that requires good toughness properties. To overcome the brittleness problem, polystyrene is modified with rubber to improve its mechanical properties, etc. Polystyrene is also very flammable, flame retardants are used to lower the flammability of polystyrene. [Pg.758]

Murphy, J. Modifying specific properties flammability-flame retardants. In Additives for Plastics, Handbooks, pp. 115-140. Elsevier Science Ltd., New York (2001)... [Pg.11]

Modifying Specific Properties Flammability - Flame Retardants... [Pg.115]

Antimony Oxide as a Primary Flame Retardant. Antimony oxide behaves as a condensed-phase flame retardant in cellulosic materials (2). It can be appHed by impregnating a fabric with a soluble antimony salt followed by a second treatment that precipitates antimony oxide in the fibers. When the treated fabric is exposed to a flame, the oxide reacts with the hydroxyl groups of the cellulose (qv) causing them to decompose endothermically. The decomposition products, water and char, cool the flame reactions while slowing the production and volatilization of flammable decomposition products (see Flaa retardants for textiles). [Pg.455]

Poly(vinyl chloride). PVC is a hard, brittle polymer that is self-extinguishing. In order to make PVC useful and more pHable, plasticizers (qv) are added. More often than not the plasticizers are flammable and make the formulation less flame resistant. Flammability increases as the plasticizer is increased and the relative amount of chlorine decreased, as shown in Table 7. The flame resistance of the poly(vinyl chloride) can be increased by the addition of an inorganic flame-retardant synergist. [Pg.459]

Table 8. Flammability of Flame-Retardant-Treated Flexible PVC ... Table 8. Flammability of Flame-Retardant-Treated Flexible PVC ...
J. A. Finn, in 6th International Symposium on Flammability and Flame Retardants, Nashville, Term., 1979. [Pg.463]

Inert Gas Dilution. Inert gas dilution involves the use of additives that produce large volumes of noncombustible gases when the polymer is decomposed. These gases dilute the oxygen supply to the flame or dilute the fuel concentration below the flammability limit. Metal hydroxides, metal carbonates, and some nitrogen-producing compounds function in this way as flame retardants (see Flame retardants, antimony and other inorganic compounds). [Pg.465]

Red Phosphorus. This aHotropic form of phosphoms is relatively nontoxic and, unlike white phosphoms, is not spontaneously flammable. Red phosphoms is, however, easily ignited. It is a polymeric form of phosphoms having thermal stabiUty up to ca 450°C. In finely divided form it has been found to be a powerful flame-retardant additive (26,45—47). In Europe, it has found commercial use ia molded nylon electrical parts ia a coated and stabilized form. Handling hazards and color have deterred broad usage. The development of a series of masterbatches by Albright Wilson should facihtate further use. [Pg.476]

E. D. Weil and A. M. Aaronson, "Phosphoms Flame Retardants—Meeting New Requirements," iu Proceedings of the 1st European Conference on Flammability and Fire Retardants, Brussels, Belgium, July 1977, Technomic Publishing Co., Westport, Coim., 1978. [Pg.483]

Dehydration or Chemical Theory. In the dehydration or chemical theory, catalytic dehydration of ceUulose occurs. The decomposition path of ceUulose is altered so that flammable tars and gases are reduced and the amount of char is increased ie, upon combustion, ceUulose produces mainly carbon and water, rather than carbon dioxide and water. Because of catalytic dehydration, most fire-resistant cottons decompose at lower temperatures than do untreated cottons, eg, flame-resistant cottons decompose at 275—325°C compared with about 375°C for untreated cotton. Phosphoric acid and sulfuric acid [8014-95-7] are good examples of dehydrating agents that can act as efficient flame retardants (15—17). [Pg.485]

The binder system of a plastic encapsulant consists of an epoxy resin, a hardener or curing agent, and an accelerating catalyst system. The conversion of epoxies from the Hquid (thermoplastic) state to tough, hard, thermoset soHds is accompHshed by the addition of chemically active compounds known as curing agents. Flame retardants (qv), usually in the form of halogens, are added to the epoxy resin backbone because epoxy resins are inherently flammable. [Pg.530]

The UL flammability ratings describe the relative ease of ignition and combustibiUty of plastics. Tests include the measurement of flame propagation, time to self-extinguish, melt and drip with and without flame, and oxygen indexes. Some engineering plastics, eg, polyetherimides, are, as ranked by this test, inherently nonflammable. Others can be made nonflammable by compounding with flame retardants (ERs) such as bromine... [Pg.264]

Flame Retardants. Most polymers, because they are organic materials, are flammable. Additives that contain chlorine, bromine, phosphorous or metallic salts reduce the likelihood that combustion will occur or spread. [Pg.3]

Ironically, the reactor was used to produce Antiblaze 19, a flame retardant used in textiles and polyurethane foam. Antiblaze 19 is a cyclic phosphorate ester produced from a mixture of trimethyl phosphite, dimethyl methylphosphonate (DMMP), and trimethyl phosphate (TMOP). The final product is not considered flammable, but trimethyl phosphite is moisture sensitive and flammable, with a flash point of about 27 C. [Pg.259]

Reduction in flammability is achieved by the incorporation of flame retardants into the polymer. Two possible approaches to this are available either the use of additives blended into the polymer at processing stage (additive type) or the use of alternative monomers which confer reduced flammability on the final product (reactive type). A number of elements have been found to assist with conferring flame retardancy on polymers, the main ones being bromine, chlorine, nitrogen, and phosphorus. [Pg.120]


See other pages where Flammability/flame retardation is mentioned: [Pg.305]    [Pg.324]    [Pg.160]    [Pg.305]    [Pg.324]    [Pg.160]    [Pg.203]    [Pg.457]    [Pg.485]    [Pg.485]    [Pg.322]    [Pg.467]    [Pg.465]    [Pg.516]    [Pg.524]    [Pg.124]    [Pg.73]    [Pg.15]    [Pg.131]   


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