Urethane flammability

Chemical Reactivity - Reactivity with Water Reacts violently to form flammable hydrocarbon gases Reactivity with Common Materials Not compatible with silicone rubber or urethane rubbers Stability During Transport Stable Neutralizing Agents for Acids and Caustics Not pertinent Polymerization Not pertinent Inhibitor of Polymerization Not pertinent. 

Urethane Liquid Exceptional abrasion, cut, and tear resistance. Poor moisture and heat resistance. Variety of formulations leading to different properties including range of durometers without plasticizers. Antistatic rollers and tires, hose for transfer of flammables, strain gages, pressure transducers. 

Aryloxyphosphazene copolymers can also confer fireproof properties to flammable materials when blended. Dieck [591] have used the copolymers III, and IV containing small amounts of reactive unsaturated groups to prepare blends with compatible organic polymers crosslinkable by the same mechanism which crosslinks the polyphosphazene, e.g. ethylene-propylene and butadiene-acrylonitrile copolymers, poly(vinyl chloride), unsaturated urethane rubber. These blends were used to prepare foams exhibiting excellent fire retardance and producing low smoke levels or no smoke when heated in an open flame. Oxygen index values of 27-56 were obtained. 

Aryl phosphates were introduced into commercial use early in the twentieth century for flammable plastics such as cellulose nitrate and later for cellulose acetate.26 In vinyls (plasticized), arylphos-phates are frequently used with phthalate plasticizers. Their principal applications are in wire and cable insulation, connectors, automotive interiors, vinyl moisture barriers, plastic greenhouses, furniture upholstery, and vinyl forms. Triarylphosphates are also used, on a large scale, as flame-retardant hydraulic fluids, lubricants, and lubricant additives. Smaller amounts are used as nonflammable dispersing media for peroxide catalysts. Blends of triarylphosphates and pentabromodiphenyl oxide are extensively used as flame-retardant additives for flexible urethane foams. It has been also... 

Burning may be considered another means of oxidation. Non-burning plastics are a must in commercial constructions according to building codes and are often required for automotive, electronic, and electrical applications. From the numerous thermoplastics, only the halogen-containing polymers, polyamides, polycarbonate, poly(phenylene oxide), polysulfone, and polyimides are self-extinguishing. Even these, such as poly (vinyl chloride), may become flammable when plasticized with a flammable plasticizer. Fire control can be the key to volume use of plastics. Polyester panels, urethane foam, and PVC tarpaulins account for nearly 90% of all fire retardants consumed. Consumption in 1967... 

Polyurethane (poly- ester/polyether urethane) Hygenic Corp. (HC480ARJ Nalgene 8030 Contains no plasticizers. Can be used both for vacuum or pressure systems. Has higher chemical resistance to fuels, oils, and some solvents than does PVC tubing. Not autoclavable, stiffer than PVC, flammable, not recommended with strong acids or alkalis. 

Flame Retardants. Among the isocyanate-based foams, polyurethane foams, both flexible and rigid, are flammable. Due to serious fire hazards of polyurethane foams, strict fire regulations have come out on the use of foams in the areas of furniture and public transportation. In addition, the use of rigid urethane foams in building insulation have resulted in stricter fire regulations. 

The high flammability and toxic-gas generation of flexible and rigid urethane foams have been major problems in the urethane-foam industry, and accordingly considerable efforts have been focused on the production of substantially flame-retardant flexible foams. 

A number of flame retardants for rigid urethane foams have been developed over the past 30 years. Nevertheless, substantially flame-retardant, and fire-resistant rigid foams are not available, because the urethane linkage is thermally unstable and decomposes to produce low-molecular-weight flammable compounds. 

The addition of flame retardants, either additive or reactive types, can provide flame-retardant foams having low flame spread or surface flammability, but flame retardants do not improve the temperature resistance of these foams because the thermal stability or the dissociation temperature of the urethane linkage is relatively low and unchanged by the addition of flame retardants, i.e., the linkage dissociates at about 200°C to form the original components in polyol and polyisocyanate. The dissociation can result in further decomposition of polyol and polyisocyanate into low-molecular-weight compounds at elevated temperatures. For these reasons urethane foams are not temperature-resistant nor thermally stable. 

Urethanes pose severe handling problems. The material, when vaporized, is flammable and can cause serious respiratory system effects. In common with the acrylics, the end product (if fully reacted) poses no health problems. 

The above cited diol, when incorporated into a flexible polyurethane foam formulation at a 5.6% level (10 phr based on the polyol) produced a self-extinguishing urethane foam, based on the Motor Vehicles Safety Standard 302 Flammability Test. 

This forecast assumes that the furniture segment is fully penetrated by flexible urethane foam. Style changes may impact cushion dimensions somewhat, but are considered an insignificant factor in the forecast. Flammability issues remain unsettled however, this forecast assumes technology development will continue to keep urethane foam in the forefront as the best choice for cushioning applications. 

Finally, urethane foams will have a flammability performance permitting their general use in non-residential occupancies. These would include high risk mattress and later furniture uses. 

Forms explosive materials with carbamates, 3 -methyl-2-nitrobenzanilide (pyrophoric), nitrobenzene, urethane. Attacks many metals with the formation of flammable hydrogen, in the presence of moisture. Attacks some plastics, rubber, and coatings. Store under nitrogen or other inert gas blanket. 

TRIISOBUTYLALUMINUM (100-99-2) Extremely flammable liquid (flash point <39°F/<4°C). Pyrophoric ignites spontaneously on contact with air. Reacts with water. A strong reducing agent. Violent reaction with oxidizers. Reacts with acids, carbon dioxide, alcohols, amines, ammonia, halogens, halogenated hydrocarbons. Attacks silicone and urethane rubbers. Store under inert gas blanket. Reacts with most common fire extinguishers ... 

Poly(urethane) foams based on polyethers have now largely replaced polydiene rubbers in upholstery and flammability is a major disadvantage compared with traditional upholstery. A major problem is that it is not the fire itself that kills people but the toxic fumes that are produced in the smoke and this is exacerbated by certain types of flame retardant. There are no simple solutions to this problem. Foams in their very nature have a large surface area and a developing fire thrives on the accessibility of fuel from the exposed foam (Chapter 3). The most promising solution is to make the textile fabric surrounding the foam non-flammable so that the fire never reaches the foam itself. 

Rigid Thermoplastic Polyurethanes Rigid thermoplastic polyurethanes are not chemically cross-linked. Has high abrasion resistance, good retention of properties at low temperatures, but poor heat resistance, weatherability, and resistance to solvents. Rigid thermoplastic polyurethanes are flammable and can release toxic substances. Processed by injection molding and extrusion. Also called Rigid Thermoplastic Urethanes and Nonelastomeric Thermoplastic Polyurethanes. 

HMIS Health 3, Flammability 1, Reactivity 1 Uses Coupling agent for epoxies, phenolics, melamines, nylons, PVC, acrylics, urethanes, nitrile rubbers crosslinking agent adhesion promoter for coatings in food-pkg. adhesives Regulatay FDA 21CFR 175.105... 

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